1930 Model AA Cant Get Her Over 25 MPH

[Working Class Zero]

Just picked up a 1930 Model AA. Nice older restore stock original. Got her home, fired right up, sounded great, running strong. Then I go for a drive....... She won't get past 25 MPH. In third gear pedal to the metal and she just won't go any faster, rpm's are not even high, but 25 MPH is it on a flat road, hit a hill and its worse. So I looked her over a bit and found a 1 inch hairline crack in the intake manifold. Could this be the issue? Ordered a new one regardless, but any advice on figuring out the lack of speed is appreciated. I know these don't go fast, but 25 MPH? Also what would be the top speed on a AA? Less than a regular pickup I hear. Thanks for any help guys.

[Bob C]

I don't know about 3rd gear but if you have a low speed rear axle 35 in 4th is about it, a
high speed rear axle about 45.

Bob

[TinCup]

There are more than a few items to check so start a list. You already have indicated one so here are a few more.
1. Where was the timing when you were in 3rd gear. It should have been all the way down on the column.
2. Verify the points and the timing at the distributor.

[Working Class Zero]

So is there a simple way to determine if I have a high or low speed rear axle?

[Working Class Zero]

Originally Posted by TinCup

There are more than a few items to check so start a list. You already have indicated one so here are a few more.
1. Where was the timing when you were in 3rd gear. It should have been all the way down on the column.
2. Verify the points and the timing at the distributor.

Timing was all the way down on the column in third. Here's some more symptoms:

Have a drip leak at bottom of the carb.

Also in the very short first drives It seems to have dropped from 1/2 a tank of fuel to near empty, as far as the gauge says, in a matter of 4 10 minute drives.

Plugs are blackened around base but clean at gap.

[columbiA]

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30-31 AA,s use the 4-speed trans.Low speed RE is 6.6-1 ratio,high speed RE is 5.14-1 ratio. High speed gears increase speed just over 28 %.Hi speed gears are stamped 7-36 in numbers 1/2" high on axle hsg.Only HS ratio is stamped on hsg.Info from page 438 of Model A service bulletins. AA,s had to be low geared in order to pack several tons of freight with only 40 HP.If you could find a 3-speed warford aux trans for an AA,that would give you an under,direct & an overdrive.It replaces the coupling shaft assy.With the OD it may approach a 4-11 ratio which is still a little slower than the average A that is 3-78 ratio.

[Working Class Zero]

Appreciate the help guys..... This is my first time with a model A original motor and I'm loving it, however a bit in the dark so far.

[Working Class Zero]

Originally Posted by columbiA

30-31 AA,s use the 4-speed trans.Low speed RE is 6.6-1 ratio,high speed RE is 5.14-1 ratio. High speed gears increase speed just over 28 %.Hi speed gears are stamped 7-36 in numbers 1/2" high on axle hsg.Only HS ratio is stamped on hsg.Info from page 438 of Model A service bulletins. AA,s had to be low geared in order to pack several tons of freight with only 40 HP.If you could find a 3-speed warford aux trans for an AA,that would give you an under,direct & an overdrive.It replaces the coupling shaft assy.With the OD it may approach a 4-11 ratio which is still a little slower than the average A that is 3-78 ratio.

Good info!
Cant see any markings. Dang. They would be on the rear axle where? On the Center or shaft? Wonder how hard a Warford Aux Trans is to find. This was going to be my daily driver shop truck but if I'm locked down at 35 MPH ouch. I don't mind join slow but..........

[Mike V. Florida]

How about placing the tranny in fourth, taking out the plugs, jacking up the rear and counting the number of enging rotations with the crank to make the wheels make one revolution? This should give you the rear end ratio. (I don't think truck 4th is OD)

[rollingsculpture]

heres the stamp on my AA rear diff fastest i can go on this boy is 53 on a downhill slop avg fast speed is 48 comfortable is 43-45 . all brakes in good shape and stops fast when needed . point gap is 20 spark plug gap at 35 timing set at absolute tdc , noted here that when i had my head off i looked at the piston location when the timing pin was set in position and found that the piston was apx 3/16 below deck , rotated the crank a hair more to absolute tdc and set my points to open there , that truck starts right up ! and runs nice ... good luck if you have the high speed rear you will get there . may be your carb too what are you running?

[Working Class Zero]

Originally Posted by rollingsculpture

heres the stamp on my AA rear diff fastest i can go on this boy is 53 on a downhill slop avg fast speed is 48 comfortable is 43-45 . all brakes in good shape and stops fast when needed . point gap is 20 spark plug gap at 35 timing set at absolute tdc , noted here that when i had my head off i looked at the piston location when the timing pin was set in position and found that the piston was apx 3/16 below deck , rotated the crank a hair more to absolute tdc and set my points to open there , that truck starts right up ! and runs nice ... good luck if you have the high speed rear you will get there . may be your carb too what are you running?

ok i definitely don't have that stamping. the previous owner said he would get it going 45 MPH easily but thats about it. Liar? Unfortunatly I had it shipped to me from afar so no test drive. I can only get 25 MPH. That is sloooow. Even for the low geared AA. Running the Zenith Carb original. But she leaks. All I want To go is about 45Mph, not looking for anything more, but less is not ideal. Anybody got a high speed diff for sale? shoot.......

[pat in Santa Cruz]

check timing for sure, as too retarded will rob top end power.. Its not an uncommon situation. Your leaky manifold will decrease power too. Check it when you get the new one and be sure both manifolds are flat and with the ports in a straight line. You might have to have them surfaced. Check that your brakes are not dragging. A compression check never hurts, and it will give you a starting indication of the internal condition.

Once you get it running right, you can make it stronger with high compression head, cam, better breathing.

Once you get it up and running strong, you can always get a Mitchell Overdrive for it. I know someone around here with a 31 AA flatbed that goes 70.

[Working Class Zero]

Originally Posted by pat in Santa Cruz

check timing for sure, as too retarded will rob top end power.. Its not an uncommon situation. Your leaky manifold will decrease power too. Check it when you get the new one and be sure both manifolds are flat and with the ports in a straight line. You might have to have them surfaced. Check that your brakes are not dragging. A compression check never hurts, and it will give you a starting indication of the internal condition.

Once you get it running right, you can make it stronger with high compression head, cam, better breathing.

Once you get it up and running strong, you can always get a Mitchell Overdrive for it. I know someone around here with a 31 AA flatbed that goes 70.

Ok now I'm getting some hope back. lol. This girl does have a '32 head on it, don't know if that is an improvement or not. Gonna look into the mitchell overdrive. Does it screw with the stock look at all? 70MPH? Whoally Crap.

[Working Class Zero]

Wow Mitchell overdrive is not cheap and will really look unoriginal under the truck. Sounds like a nice unit though. Is it not possible to just get the higher gears for my diff, and switch em out?

[columbiA]

Model B head is 4.6 c/r,A head is 4.2 c/r,so there is a slight improvement.If engine is in good condition,install a 5.5 or 6.0 c/r head and you will notice a real increase in power.

[pat in Santa Cruz]

a 32 head makes little difference. It breathes a bit better, but only raises the compression from 4.2 to 4.4 or 4.5 ( can't remember right now), not much.. A Mitchell OD has another shift lever in the cab, which is the give away. Two shift levers in an AA cab is not as unusual looking as in a car. The undercarriage will look different. The OD unit replaces the intermediate shaft behind the transmission. They'll have to know which shaft you have, short or long.

before you start adding power accessories to the engine, you must determine if its basically sound. That is, strong crankshaft and bearings, good compression, good valves, good cooling system, good steering and brakes etc. Beefing up a worn truck will just cost you money and increase the stress on the truck. But if you want to learn more, join the AA Truck Club. Website here:
http://www.fmaatc.org/

[pat in Santa Cruz]

high ratio ring and pinions can be found. Ask around the AA club site.

[Jordan]

Originally Posted by KANE MCAFFER

Wow Mitchell overdrive is not cheap and will really look unoriginal under the truck. Sounds like a nice unit though. Is it not possible to just get the higher gears for my diff, and switch em out?

You can paint the box black so that it doesn't stick out. Trust me, once you have an overdrive, you'll never regret it.

[Tom Wesenberg]

Did you really have it in 3rd gear?
4th gear is to the right and back and is straight through, just as third gear is in the cars.

As mentioned to check the rear end ratio, jack up one rear wheel, shift to 4th gear, and count how many engine revolutions it takes to turn the rear wheel exactly two full turns. It takes two full turns because one wheel is on the ground and the differential then turns the loose wheel twice as fast.

[CarlG]

What are you calling 3rd gear? In an AA with a 4-speed transmission, 3rd is not "High" gear. It would be equivelant to 2nd in an A with a 3-speed transmission, notwithstanding the rear end ratios. Back in the '50s I had an AA 280A with a 4-speed transmission and on flat ground had no trouble cruising at 50-55 (in 4th gear). I was a teenager then so it was usually "pedal to the metal" wherever I went.

(Tom beat me to it!)

[juke joint johnny]

As Kane keeps saying 3rd gear!!! Could he have an earlier AA with the 3 speed transmission? Maybe the paperwork calls it a 1930, wouldnt be the first time
Can we see some pictures ?

[sturgis 39]

The three speeds came with the double high transmission. This the auxiliary transmission behind the three speed. It is actually an under drive transmission. It is operated with a foot pedal on the floor. When the axillary transmission is in high gear the drive is direct.
Someday, I want to mount the axillary transmission backwards and make it an over drive.

I did not know that Mitchell made an over drive for "AA" trucks.

I thought the "AA" trucks were slower than cars and never went much over 25 mph.

The three speed transmission is the same as a car three speed.

It is snowing here today.

[modeleh]

If you have a 3spd and a dual high, with the rocker pedal, perhaps the aux trans is in underdrive. Do you have a bevel gear rear or worm drive? If it it worm drive it will be a low speed rear and should have a dual high trans mounted aft of the main gearbox. Your options will be slow or slower.

[spdway1]

Originally Posted by CarlG

What are you calling 3rd gear? In an AA with a 4-speed transmission, 3rd is not "High" gear. It would be equivelant to 2nd in an A with a 3-speed transmission, notwithstanding the rear end ratios. Back in the '50s I had an AA 280A with a 4-speed transmission and on flat ground had no trouble cruising at 50-55 (in 4th gear). I was a teenager then so it was usually "pedal to the metal" wherever I went.

(Tom beat me to it!)

Do you mean Pedal to the WOOD?

[kp]

Maybe I missed something from above post ,did anybody mention checking the throttle opening to be sure its opening fully ,mash the pedal to the 'wood ' and check while its down to see if the throttle is opening fully.

[ronn]

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remove the ball and chain and set her free......

[ctlikon0712]

Check to make sure that your advance lever on the collumn moves that advance plate in the dist. all the way advanced to the counter clockwise position...... looking down from the top. The advance tab lever should be all the way up against the stop in the distributor's window.

[flatford39]

30 and 31's were 4 speed transmissions. I have a feeling you may have a very early 30 with the 3 speed trans and the hi lo underdrive. Are there two pedals sticking up behind where your right foot rests??? If so that is the underdrive and I bet you are in creeper mode. You need to depress the pedal with the clutch in to get to normal driving. You should be able to do 35 MPH to 40MPH even with the low speed rear.

[Bob C]

The 4speed came out in Oct '29.

Bob

[flatford39]

Originally Posted by Bob C

The 4speed came out in Oct '29.

Bob

Yeah..but he talks about when he is in 3rd gear he can't get over 25MPH. Maybe he has a 29 and not a 30.

[Mike V. Florida]

Originally Posted by ronn

remove the ball and chain and set her free......

I thought this was about a truck not a wife?

[Bob C]

OK Kane how about some pictures

[BILL WILLIAMSON]

Tip # 17-Just in case it an exhaust flow problem, hook up a vacuum guage and slowly keep speeding up the motor and see if the vacuum gage gradually goes to zero. Sometimes even carbon deposits in the muffler can cause restriction. If mouse nest or carbon is suspected, lean the complete exhaust system, outdoors of course, on a 45 degree angle, wih tail pipe up. Slowly pour diesel into tail pipe unil it trickles out header pipe. Light the diesel at the lower end with a piece of newspaper. Once lit, it will "draw" like a chimney. Keep adding diesel from upper end until the whole thing is glowing RED! Cool it off and put it back on.
Roar the engine & you'll be surprised how much soot, scale & crap comes out that has accumulatd for 80 something years!! A friend did this and increased top speed from 52 MPH to 62 MPH! It's kinda' like when we're sluggish and have to resort to a laxative! Bill W.

[juke joint johnny]

BIll I like your tip *17
You have a lifetime experience of these cars & still remember how things were done in the old days with no money, tools or electricity!!!
To some peoples surprise these remedies actually worked and if they didn't work we wouldn't have so many Model A 's left in the World today.
Some people get so technical you would think they are talking about a Nasa rocket not a basic car from the 1920's
You should write all these tips down in a book or website or something so we can refer to them in the future.
Give the Rat terrier a pat from me
John Cochran

[pat in Santa Cruz]

Bill, I like the sound of this. I'm working on a 25 Buick right now with a restricted muffler, probably a rat nest judging from the smell of the exhaust. I'm gonna give this a try. The other alternative is to shell out bucks for another muffler which is no fun. I have lots of old diesel around and besides, playing with fire always was something I enjoyed.

And along the line of looking for other causes: It was mentioned above that Kane should check the throttle for full opening. That's a good tip. Bent throttle brackets are common, and can result in incomplete opening as well as a refusal to fully closing to idle.

[BILL WILLIAMSON]

Originally Posted by pat in Santa Cruz

Bill, I like the sound of this. I'm working on a 25 Buick right now with a restricted muffler, probably a rat nest judging from the smell of the exhaust. I'm gonna give this a try. The other alternative is to shell out bucks for another muffler which is no fun. I have lots of old diesel around and besides, playing with fire always was something I enjoyed.

And along the line of looking for other causes: It was mentioned above that Kane should check the throttle for full opening. That's a good tip. Bent throttle brackets are common, and can result in incomplete opening as well as a refusal to fully closing to idle.

DON'T EVEN THINK ABOUT USEING GASOLINE!!
I don't want to read a headline saying, "COASTAL MAN BUILDS BOMB IN A 1925 BUICK MUFFLER!"
Bill W.

[marc hildebrant]

Is there any update on 3rd gear vs 4th gear ?

Marc

[spdway1]

Not yet Marc, we are now making muffler bombs with petroleum products, LOL!

As Toby Keith sings - "I love this bar"

[jerry of whidbey]

my AA with duals will do 40 and then some but I never do more then 40 check the cav valve to make sure it is open far enough when you get to top speed

[sturgis 39]

Originally Posted by flatford39

Yeah..but he talks about when he is in 3rd gear he can't get over 25MPH. Maybe he has a 29 and not a 30.

Some modern truck drivers consider high gear in a four speed as third gear. Some four speed shift nobs have first labeled "LO" and the others labeled as 1,2,3. He might have us all confused.

[Tom Wesenberg]

Originally Posted by sturgis 39

Some modern truck drivers consider high gear in a four speed as third gear. Some four speed shift nobs have first labeled "LO" and the others labeled as 1,2,3. He might have us all confused.

I thought of that possibility too. I wonder why he hasn't come back to clear it up?

[BILL WILLIAMSON]

Originally Posted by sturgis 39

Some modern truck drivers consider high gear in a four speed as third gear. Some four speed shift nobs have first labeled "LO" and the others labeled as 1,2,3. He might have us all confused.

Sturgis, Ghost here!
Bill W. was born "CONFUSED," and has spent 76 1/2 years trying to get his s**t together! Ha, Ha, Ha, Ha! Bill W's GHOST

[spdway1]

I hope he did not blow himself up after that "muffler tip"!

[1932BB]

Did anyone mention checking for the brake dragon?

[sturgis 39]

Originally Posted by 1932BB

Did anyone mention checking for the brake dragon?

Nobody has heard from him for days. I hope he is not mad at us. He might think we are not overly bright. Is a brake dragon different than a fire belching dragon? I think, I have seen both but it was a long time ago.

An intake manifold leak will make it run lean and slow.

[spdway1]

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[Working Class Zero]

Originally Posted by Tom Wesenberg

Did you really have it in 3rd gear?
4th gear is to the right and back and is straight through, just as third gear is in the cars.

As mentioned to check the rear end ratio, jack up one rear wheel, shift to 4th gear, and count how many engine revolutions it takes to turn the rear wheel exactly two full turns. It takes two full turns because one wheel is on the ground and the differential then turns the loose wheel twice as fast.

Guys I'm stupid not retarded. lol. 4 Speed. 1st - left 'n up, 2nd - left 'n down, 3rd - right 'n up, 4th - right 'n down, reverse - flick the thumb switch 'n right 'n back. Am I missing something?

[Working Class Zero]

holy crappy, I just realized there are like 12 posts I missed on here. I get notified by email and had got nuthin. Something must have glitched. Sorry guys, for dissapearin, but thought nobody cared about me anymore. lol. Let me read the missed posts and I get back . I Redid all the timing, gap etc, and she's running way better. hit the elusive 35 MPH, but thats it. Pretty happy bout that though. Think I need the higher gear set..........

[Working Class Zero]

Originally Posted by juke joint johnny

As Kane keeps saying 3rd gear!!! Could he have an earlier AA with the 3 speed transmission? Maybe the paperwork calls it a 1930, wouldnt be the first time
Can we see some pictures ?

Sorry I misprinted there a bit. Was getting only 25 MPH in 4th not 3rd. Meant to say that she was not at high rpm in third but just blah, then shift to 4th for lack of something better to do and slug only to 25MPH. Again timing helped and she's now at 35 MPH. So better but must be the low geared girl.

[Working Class Zero]

Originally Posted by kp

Maybe I missed something from above post ,did anybody mention checking the throttle opening to be sure its opening fully ,mash the pedal to the 'wood ' and check while its down to see if the throttle is opening fully.

Check. Did it.

[Working Class Zero]

Originally Posted by ctlikon0712

Check to make sure that your advance lever on the collumn moves that advance plate in the dist. all the way advanced to the counter clockwise position...... looking down from the top. The advance tab lever should be all the way up against the stop in the distributor's window.

Check. Did it.

[Working Class Zero]

Originally Posted by BILL WILLIAMSON

Tip # 17-Just in case it an exhaust flow problem, hook up a vacuum guage and slowly keep speeding up the motor and see if the vacuum gage gradually goes to zero. Sometimes even carbon deposits in the muffler can cause restriction. If mouse nest or carbon is suspected, lean the complete exhaust system, outdoors of course, on a 45 degree angle, wih tail pipe up. Slowly pour diesel into tail pipe unil it trickles out header pipe. Light the diesel at the lower end with a piece of newspaper. Once lit, it will "draw" like a chimney. Keep adding diesel from upper end until the whole thing is glowing RED! Cool it off and put it back on.
Roar the engine & you'll be surprised how much soot, scale & crap comes out that has accumulatd for 80 something years!! A friend did this and increased top speed from 52 MPH to 62 MPH! It's kinda' like when we're sluggish and have to resort to a laxative! Bill W.

Hmmmmmm. Interesting.....

[Working Class Zero]

Originally Posted by sturgis 39

Nobody has heard from him for days. I hope he is not mad at us. He might think we are not overly bright. Is a brake dragon different than a fire belching dragon? I think, I have seen both but it was a long time ago.

An intake manifold leak will make it run lean and slow.

Oh Ya I also replaced the intake and exhaust manifold with a Nice matched surface set I got from a buddy.

[Working Class Zero]

Originally Posted by KANE MCAFFER

Guys I'm stupid not retarded. lol. 4 Speed. 1st - left 'n up, 2nd - left 'n down, 3rd - right 'n up, 4th - right 'n down, reverse - flick the thumb switch 'n right 'n back. Am I missing something?

Ok sorry, now that I went back and read all the posts I see how I caused all the confusion. lol. Again the help is more than unbelievable, and you all are the best. Only reason I disappeared was I got no notifications of post like I usually do and had no idea this conversation was still goin on!!! Im working on getting a couple pics of the AA up here so you can see what the hell it looks like.

[sturgis 39]

There should not be a switch on the shift lever. There might be a lever on the shift lever. The little lever is for reverse. We thought the diesel fuel in the exhaust pipe might have put you in orbit.

Looking forward to the pictures. Be sure to set your camera on low setting. If they are to big they will not post. I set mine on the second lowest setting.

We are all glad you are not stupid, It sound like you have the shifting pattern correct. Glad you are back.

[Working Class Zero]

Originally Posted by sturgis 39

There should not be a switch on the shift lever. There might be a lever on the shift lever. The little lever is for reverse. We thought the diesel fuel in the exhaust pipe might have put you in orbit.

Looking forward to the pictures. Be sure to set your camera on low setting. If they are to big they will not post. I set mine on the second lowest setting.

haha, ya I meant lever......... Didn't try the muffler thing yet, gotta think about that one a bit more......... and all the pics I have are huge so ill have to take smaller ones tomorrow.........

[Working Class Zero]

Here's my next problem....... fuel mileage is el super crappo it seems so far. I fill her up and the gas gauge seems to work perfectly. but as far as that says it only took 12 miles to rip thru a 1/4 tank. Whaaaaat!?!?! What kind of mileage can you expect to get on an AA? Way worse than an A? The carb is leaking a bit but wow. I know i sound like a dork but this is the first model A/AA i have owned that is on the road. My other is a '31 roadster hot rod I'm still building and it has a flathead v8 not a 4. So bear with me, I'm learning, and love it.

[Tom Wesenberg]

You need a shut off valve and carb needle and seat the actually stop the gas flow. My 29 Tudor lost a full tank of gas in a few months because both the shutoff valve and carb leaked a bit. I took them apart and polished them with toothpaste so they stop ALL gas flow now. It doesn't take much of a leak to loose a lot of gas.

On a similar note, when I worked at the GM dealership one of the new cars came in off the transport with the oil pan drain plug not fully tightened. Over a few days the oil dripped away and when the lot boy started it to warm it up, the engine ran dry and was ruined. A very costly simple mistake for the company.

[Working Class Zero]

Originally Posted by Tom Wesenberg

You need a shut off valve and carb needle and seat the actually stop the gas flow. My 29 Tudor lost a full tank of gas in a few months because both the shutoff valve and carb leaked a bit. I took them apart and polished them with toothpaste so they stop ALL gas flow now. It doesn't take much of a leak to loose a lot of gas.

On a similar note, when I worked at the GM dealership one of the new cars came in off the transport with the oil pan drain plug not fully tightened. Over a few days the oil dripped away and when the lot boy started it to warm it up, the engine ran dry and was ruined. A very costly simple mistake for the company.

I do have a fuel shut off valve at the tank. I should check it to make sure it is functioning correctly. As far as the carb needle and seat, what are you saying, replace, clean? Toothpaste? Not sure what you mean there....

[Working Class Zero]

I'm not as much losing gas when it sits, as I am just sucking thru it when driving....../

[Tudortomnz]

I may not be adding anything, but do you have the 'mixture' [GAV] set 1/4 or less open when warmed & driving. Also, a check on the valves may help to eliminate any burnt out etc. Just a thought.

[Working Class Zero]

Originally Posted by Tudortomnz

I may not be adding anything, but do you have the 'mixture' [GAV] set 1/4 or less open when warmed & driving. Also, a check on the valves may help to eliminate any burnt out etc. Just a thought.

The mixture? GAV? Explain.

[ctlikon0712]

The GAV is an adjustment on the carb associated with the choke rod. Closed is full CW Clock Wise, gingerly not torqued. Then to start a cold engine one half to one full turn CCW Counter Clock wise , once warmed up, somewhere between fully closed to one third turn, a well running engine might like fully closed. It controlls the air fuel mixture.
Others might fine tune this statement but that is the gist.

[Rusty Homestead Fl]

Pull the muffler pipe off at the header, if possible. Take it for a drive and see if you do any better. That will tell you if the system is blocked or not.

[Working Class Zero]

Originally Posted by ctlikon0712

The GAV is an adjustment on the carb associated with the choke rod. Closed is full CW Clock Wise, gingerly not torqued. Then to start a cold engine one half to one full turn CCW Counter Clock wise , once warmed up, somewhere between fully closed to one third turn, a well running engine might like fully closed. It controlls the air fuel mixture.
Others might fine tune this statement but that is the gist.

Where exactly is that GAV adjustment on the carb? And what does GAV Stand for?

[Working Class Zero]

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gas adjusting valve? Im guessing.

[Working Class Zero]

is the GAV Adjustment actually done at the choke rod inside the cab?

[Working Class Zero]

The knob on the choke rod inside the cab is threaded on and although a hard turn, just unthreads when I turn it. Is that where I'm adjusting the GAV and if so it should not be unthreading obviously? Anxiously awaiting clarity on this whole GAV thing. Was oblivious to it completely.......

[Working Class Zero]

ok so I turned the choke rod shaft by hand. looked to be as far as she could go in a CLOCKWISE direction. So i turned it COUNTER CLOCKWISE. It goes quit a few revolutions and I see the assembly pulling out then although it still turns counterclockwise there is no more adjustment to be seen. Still spinning counter clockwise though. Is there a point where I know is fully closed in the counter clockwise position? Am I on the right track? Does what I said Make Any sense?

[1931 flamingo]

To CLOSE the GAV you turn it CLOCKwise, to open the GAV you turn it COUNTERclockwise.
To start open (CCW) the GAV about 1/2 turn, start engine, let it warm up, then adj it CW til you get a good idle and throttle response. Others will chime in I'm sure. Good luck.
Paul in CT

[Working Class Zero]

Originally Posted by 1931 flamingo

To CLOSE the GAV you turn it CLOCKwise, to open the GAV you turn it COUNTERclockwise.
To start open (CCW) the GAV about 1/2 turn, start engine, let it warm up, then adj it CW til you get a good idle and throttle response. Others will chime in I'm sure. Good luck.
Paul in CT

ok shoot mis read there. Ok that all makes sense, I'll try it............ Hows about the setting of the idle mixture screw on top of carb? I screwed with it and now its running like a bag of crap........ lol

[rollingsculpture]

screw in the idle- Air/fuel screw clock wise all the way in.... than unscrew 1 1/2 turns out to start with . start engine and note how it is running . usually 1 1/2 turns out is the right spot to get the engine running well . turning the screw in will decrease the air flow in and create a richer fuel mixture due to the decrease in air flow ..the opposite... turning the air/fuel idle screw out will increase the air flow and create a leaner air/fuel mix . too rich or too lean will make for poor idle there is a sweet spot somewhere between fully closed and 2 1/2 turns out . find it and than leave it there. as for the gav control try one full turn out and than after the engine is warmed up 1/2 turn back in to lean out the fuel flow a bit may run best anywhere from full closed to 3/4 open depends on the carb and carb condition

[Working Class Zero]

Ok, here are some photos of her........ Finally........

photo-9.jpg

DSC00459-1.jpg

DSC00451.jpg

photo-8.jpg

DSC00456-1.jpg

photo-7.jpg

[1931 flamingo]

Suweeet!!!
Paul in CT

[rollingsculpture]

good looking truck hope you get him running right than you can appreciate what you bought

[Bob C]

With those big tires you are probably going faster than your speedo reads.
What size are they, 700X20?

Bob

[Working Class Zero]

So as far as what I've covered now because of all the help of you great gentlemen:

Timing is set and bang on. (I think)
You guys can judge my method here........

1) Checked that spark advance lever was properly adjusted to touch each wall of the distributer body slot in full retarded and full advance positions. Needed to spin the steering column slightly to correct this but all good now.

2) Found top dead centre on cylinder one (cyl. at front of block).

3) Set distributer points gap at .020.

4) Loosened of Distributer cam screw, turned cam until points just ready to open and adjusted for lash. Tested this with a test light. Slightest turn on the cam screw counter clockwise when tightened back up and light comes on. With ignition on test light is off, pull timing lever on column down and light comes on at about 2 notches from top.

Learned about the GAV Adjustment (Duh)

1) Turned all the way clockwise. Half turn or so counter clockwise when starting and adjust clockwise when engine warm.
* note I don't notice much if any difference in the idle when I adjust although the idle sounds pretty good regardless. Hmmm.

Starting her with timing lever all the way up and then driving with it about 3/4 down.

Intake and exhaust manifolds replaced. I would like to test it for leaks however. Whats that trick again?

Going for test drive now. Will share results shortly............

[Working Class Zero]

Originally Posted by Bob C

With those big tires you are probably going faster than your speedo reads.
What size are they, 700X20?

Bob

Hmmmm. Had thought about that......
Tires are 6.50X20.
Is that not the stock size on an AA like this?

[mass A man]

You really need a reprint of the original owner's manual. It is not expensive and will set you straight on the Model A basics, (settings, driving, adjustments...) Your carb may need a clean/adjust, now that you may have a good manifold seal to block. Plugs should not be sooted up if you are driving with proper adjustments. Other more in-depth repair books are out there, many are a great value to the A owner. Lastly, we're always here too!---Pete.

[CarlG]

6.50 x 20 is what my AA 280A came from the factory with. (the spare was an original factory issue when I bought it in 1955)

[Working Class Zero]

Test Drive report..........

Starts up good. Idles high. GAV 1/2 turn out.
If I turn it out or counter clockwise 1-1 1/2 it helps the idle come down a bit, but if I leave it there when driving it runs rough. turn it all the way clockwise and it runs pretty good but come to a stop and she's idling quit high.

Feels pretty good for the most part when ripping along, but I'm still just literally watching my gas gauge go down. i've only driven 22 miles since i filled her right up and I'm already approaching 1/2 a tank. holy moly.

[Droobie]

Kane I am in love with your truck!!!!! It is SWEET!!!!!

[Working Class Zero]

Originally Posted by Droobie

Kane I am in love with your truck!!!!! It is SWEET!!!!!

Thanks. I am in love with it too.......
Once she's tuned in I will love her even more.......

[ctlikon0712]

Maybe your throttle shaft on the carb is pulling in air at idle. When you back the Idle speed screw out all the way does she want to die? If not its pulling air in around the shaft where its worn in the carb housing or the throttle shaft and butterfly valve arent lined up correctly in the bore. If she does want to die then you adjusted the Idle mixture somewhere around 1.5 turns out and reset the Idle speed right? They temd tp react to each other so you might have to go back and forth a few times with them.

[theHIGHLANDER]

Kane, I'm going to avoid the xmas rush and start hating you now. That truck is seriously F'n sweet!

Ok, I'm going to throw some observations at ya. You turned the column to correct your timing range. You may have moved the warm up throttle outta range a bit. High idle. Mileage concerns, if you're turning the GAV that much and it runs ok until idle, well then at idle it's running too fat. Trust it. If it idles good and runs good warmed up at 1/2 to 3/4 out on the GAV, leave it alone until you drive it cold weather. The idle mixture screw, with everything else good and your timing at 1/2 or so, adjust the idle no more than 1/8 turn at a time and let the motor "catch up" to that adjustment. You'll find the sweetest spot when you hear a difference in the "hiss" of mixture in the carb. It'll be silent when it's way in, sound "wet" or a bit bubbly when it's way out, but right before that sound gets completely audible, that's usually the sweet spot. Needle and seat needs to function properly. Under load, a big truck like that will drink almost all the fuel you give it. It's heavy, it's not the same as the cars, it's gonna be a bit thirstier, but I'm with you about too much gas being used. I drove my pickup about 20 miles give or take and didn't even notice the movement of the fuel level. Around 3/4 when I drove it, around 3/4 when I drained it, now reads empty. Control your fuel flow and you are home free. Again, as big and heavy as it is, it'll probably use extra fuel that cars would be smokin and belching over.

Did I say your truck was bitchin? It is. Hang in there bro, you'll get it.

[Bob C]

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Dual wheel trucks had 6.00 x 20 front and rear, trucks with single wheels had 6.00 x 20 on
the front and 32 x 6 (6.50 x 20) on the rear according to the Service Bulletins.

Bob

[Working Class Zero]

Originally Posted by ctlikon0712

Maybe your throttle shaft on the carb is pulling in air at idle. When you back the Idle speed screw out all the way does she want to die? If not its pulling air in around the shaft where its worn in the carb housing or the throttle shaft and butterfly valve arent lined up correctly in the bore. If she does want to die then you adjusted the Idle mixture somewhere around 1.5 turns out and reset the Idle speed right? They temd tp react to each other so you might have to go back and forth a few times with them.

Craig, I fired it up and backed off the Idle speed screw and it just kept running exactly the same. No fluctuation in the idle whatsoever. I even took the screw right out and she was still running strong, with no difference.

[Working Class Zero]

Originally Posted by KANE MCAFFER

Craig, I fired it up and backed off the Idle speed screw and it just kept running exactly the same. No fluctuation in the idle whatsoever. I even took the screw right out and she was still running strong, with no difference.

So what would be my next step if this is happening.......

[ctlikon0712]

Got to find where the air is comming from around the butterfly. Take the throttle and pull the top back. Should try to close it further. Does engine slow? If not put your hand over the carbs opening. Does it then want to die, or do you hear the his of air from somewhere? Maybe where the shaft goes throught the housing? If not the butterfly plate might have been installed in the shaft wrong and not be sealing up against the bore all the way. Also, check where the carb bolts to the intake. Could the ears be bent where it mates up, or a bad gasket? Sucking air there? Let us know.

[Tom H.]

Kane, very nice truck. With 6:00 - 20 rear tires our 32 AAB will run about 45mph, but feels comfortable in the 35 - 40 range. I don't know the mpg but it seems like every time I run her around for a few miles it takes another gallon. Best of luck with the big iron.
Tom H

[Modelakid31]

I would run the spark all the way advanced(down) when driving normal flat'ish roads and then when going up an incline or hill bring the spark up to adjust the power needed.

Especially if the engine is timed right run with the spark all the way down. shouldnt be a problem.

[Modelakid31]

also, Beautiful truck! she's a keeper!

[Working Class Zero]

Originally Posted by ctlikon0712

Maybe your throttle shaft on the carb is pulling in air at idle. When you back the Idle speed screw out all the way does she want to die? If not its pulling air in around the shaft where its worn in the carb housing or the throttle shaft and butterfly valve arent lined up correctly in the bore. If she does want to die then you adjusted the Idle mixture somewhere around 1.5 turns out and reset the Idle speed right? They temd tp react to each other so you might have to go back and forth a few times with them.

Sorry I think i got mixed up with all the "screw names". When you say: "When you back the idle speed screw out all the way does she die" you mean the screw on the throttle lever as opposed to the idle mixture screw on top of the carb right? I had thought we were talking about the one on top. If I back off the screw on the throttle lever she does die and I get get a nice sounding idle if I adjust there.

Again when I said I backed it out all the way and there was no fluctuation in idle I was referring to the idle mixture screw on top.

Adjusted at throttle lever to nice idle does however now stop it from going full throttle with the pedal to the wood.........

[Working Class Zero]

I also have a family of birds nesting in the rafters of my shop. They are very loud, however not causing any of my AA problems........ lol

[1931 flamingo]

Kane: With engine running take a spray can of wd-40 and spray around the gasket areas of the intake/exhaust manifolds, if there is a leak the idle will smooth out. Does your intake manifold have a vacuum fitting (for w/shield wipers)?? Ck that line for leaks, also the vac hose that runs from top of header over to the wiper motor.
paul in CT Isn't this fun?

[Working Class Zero]

Originally Posted by 1931 flamingo

Kane: With engine running take a spray can of wd-40 and spray around the gasket areas of the intake/exhaust manifolds, if there is a leak the idle will smooth out. Does your intake manifold have a vacuum fitting (for w/shield wipers)?? Ck that line for leaks, also the vac hose that runs from top of header over to the wiper motor.
paul in CT Isn't this fun?

Wd40, that was it...... Gonna try that. No wiper vacuum, intake is an original, but must have been off a roadster or something with a hand operated wiper.

[ctlikon0712]

Yes, the Idle speed and Idle mixture are two different things but if you change the idle speed(screw on the lever), it moves the butterfly and changes the Idle mixtures(screw on top) setting so you have to readjust it somewhat. Yea so the mixture you want in all the way and back out 1.5 turns and then play with it at a low idle speed to get the best idle. Should be between 1 to 2 turns off the seat position.

[Tudortomnz]

Originally Posted by mass A man

You really need a reprint of the original owner's manual. It is not expensive and will set you straight on the Model A basics, (settings, driving, adjustments...) Your carb may need a clean/adjust, now that you may have a good manifold seal to block. Plugs should not be sooted up if you are driving with proper adjustments. Other more in-depth repair books are out there, many are a great value to the A owner. Lastly, we're always here too!---Pete.

I think this is very good advice to someone new to stock Model A's. A reprint handbook will tell you how to start, drive & look after the vehicle.

[dmaxweb]

Originally Posted by KANE MCAFFER

Sorry I think i got mixed up with all the "screw names". When you say: "When you back the idle speed screw out all the way does she die" you mean the screw on the throttle lever as opposed to the idle mixture screw on top of the carb right? I had thought we were talking about the one on top. If I back off the screw on the throttle lever she does die and I get get a nice sounding idle if I adjust there.

Again when I said I backed it out all the way and there was no fluctuation in idle I was referring to the idle mixture screw on top.

Adjusted at throttle lever to nice idle does however now stop it from going full throttle with the pedal to the wood.........

All about zenith carbs
http://www.model-a.org/default.html

[Working Class Zero]

Originally Posted by dmaxweb

All about zenith carbs
http://www.model-a.org/default.html

Good link thanks.......

[Working Class Zero]

No leaks detected at manifolds on wd40 trick. I think I have it kinda dialled in now, but hey its hard to tell how good its actually running when you have no stock model A driving experience to compare to.....

[Working Class Zero]

Originally Posted by Tudortomnz

I think this is very good advice to someone new to stock Model A's. A reprint handbook will tell you how to start, drive & look after the vehicle.

This is true and I have ordered some literature, but I'm waiting for it to arrive and I am not a patient person. LOL. Lot of great help here too, so, thanks guys....

[dmaxweb]

Originally Posted by KANE MCAFFER

No leaks detected at manifolds on wd40 trick. I think I have it kinda dialled in now, but hey its hard to tell how good its actually running when you have no stock model A driving experience to compare to.....

No Model A clubs around?
Your profile does not say where you live.

[Working Class Zero]

Originally Posted by dmaxweb

No Model A clubs around?
Your profile does not say where you live.

I live on Vancouver Island, British Columbia, Canada. No model A clubs, Unless I start my own, lol.

[1930artdeco]

Hi Kane,

I love the truck! your truck is doing what my car did. I would adj. the idle air screw and nothing would change at all. I discovered that the throttle hsaft was worn and decided to put in an oversized shaft. So I ordered one only to find out that I already had one in the carb. The replacement shaft would not let me adj. the carb correctly as the screw plate had the incorrect angles-gone.

I also sealed up the inside hole (against the engine) where the shaft goes with JB Weld and put some thick grease around the throttle shaft on the outer side. She quit sucking air around the shaft and idles much better now.

Mike

[Bruce Adams]

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I see about fifteen MAFCA memberships on VANCOUVER, BC, Canada in my 2012 MAFCA Roster. I would think that would represent at least sixty Model A Owners on your island. You might want to reach out to some of them for assistance right at the truck instead of through sep by step correspondence. There is even more knowledge "Out There" than on line, many of whom would just love to assist with this simple problem.
Email me and I would be pleased to provide some names and phone numbers.
[email protected]
Good Luck !

[CarlG]

Vancouver Island and Vancouver BC are separated by a body of water. You have to take a ferry to get from one to the other. That doesn't mean there aren't any on the island though. Try looking for someone in Victoria BC.

[Working Class Zero]

I have my connections, one of which lives right in my town and pretty much knows all about A's. I actually enjoy getting feedback on this forum from all you experienced cats and often like to work quietly alone in my shop, if that makes any sense. Plus the more people I get info from, the more I learn. I always want to learn something new. Lastly I thought it would be nice to get on here and say hello now that I own a stock AA...........Hey isn't this sort of stuff what this forum is all about? Appreciate the help on finding local model A guys too, don't get me wrong. Thanks again guys!!!

[flatford39]

Originally Posted by KANE MCAFFER

I have my connections, one of which lives right in my town and pretty much knows all about A's. I actually enjoy getting feedback on this forum from all you experienced cats and often like to work quietly alone in my shop, if that makes any sense. Plus the more people I get info from, the more I learn. I always want to learn something new. Lastly I thought it would be nice to get on here and say hello now that I own a stock AA...........Hey isn't this sort of stuff what this forum is all about? Appreciate the help on finding local model A guys too, don't get me wrong. Thanks again guys!!!

You bet it is and I feel the same way about working on my stuff. Been to your island and really loved it. Not sure why you would want to go faster than 35MPH there as the scenery is quite beautiful.

[ctlikon0712]

I think the gas gage and mileage is the real prob.... Are the plugs still looking black?. Maybe when the carb was rebuilt, someone left a jet out or somthing......

[Working Class Zero]

Originally Posted by ctlikon0712

I think the gas gage and mileage is the real prob.... Are the plugs still looking black?. Maybe when the carb was rebuilt, someone left a jet out or somthing......

I agree. Waiting on plugs in mail, so not changed yet. I'm half ways thinking of just ordering a new carb from Macs or Bratton's or sum thin to just to know all is new and proper. Never been the slickest with carb rebuilds or anything to do with the damn things. Could take it off and apart I guess and try to troubleshoot but.........

[modeleh]

Kane, I am in Nanaimo and have some extra bits and pieces if there's anything that you may need help with, just send me a pm, I am on the AA site also.
Did you find your truck locally? It looks to be in great shape. There are only a handful of running AAs on the island that I know of, one similar to yours in Saanich.

[Working Class Zero]

Originally Posted by modeleh

Kane, I am in Nanaimo and have some extra bits and pieces if there's anything that you may need help with, just send me a pm, I am on the AA site also.
Did you find your truck locally? It looks to be in great shape. There are only a handful of running AAs on the island that I know of, one similar to yours in Saanich.

Nice to meet ya. You have an AA too?

[sturgis 39]

The carbs are easy to work on and simple. I think I would play with GAV and run a little lean or when the RPM goes high. Then adjust the idling screw when the idle is too high. The idle screw is on the throttle linkage. Make sure you throttle lever is all the way up when playing with the idle screw. Do not be afraid to take the carb apart. They are pretty simple. The biggest problem I have had is the rust from the gas tank plugging up the sediment bowl and the little screen in the carburetor. I bought a stand pipe filter from one of the parts places. The stand pipe slips into the shut off valve in the tank and keeps the sediment in the tank. I also run a see through inline filter between the tank shut off valve and the sediment bowl. I still get rust after ten years.

Get a can of carb cleaner at Walmart- It Is cheap and good-High tech is their trade mark name. Other carb cleaners are good and wear glasses- you never know what little hole that stuff will blow out. There might be a plug on the bottom of the carb and I would take that out first. Water is heavier than gas and It might have some moisture in the bowl.

It will take some tinkering so do not get discouraged. I do not think you will get much more than 30 mph. The black plugs and poor mileage kind of indicate a rich mixture. The gas gauges are kind of on again and off again.

[dmaxweb]

Originally Posted by KANE MCAFFER

I agree. Waiting on plugs in mail, so not changed yet. I'm half ways thinking of just ordering a new carb from Macs or Bratton's or sum thin to just to know all is new and proper. Never been the slickest with carb rebuilds or anything to do with the damn things. Could take it off and apart I guess and try to troubleshoot but.........

If you are looking for a carb rebuilder, I would contact Ross Henderson, 9949 Seymour St., Santee, California (619) 871-0201. Excellent work! He also sells on ebay as "tazman24282428". I would contact him directly rather than ebay.

No affiliation, just a happy customer.

[Working Class Zero]

So my wife tells me about this application you can get on your iPhone. A speedometer. She says it works exactly accurate. I'm like ya right...... So I try it. I turn it on and go for a drive in our brand new mini van (don't tell anybody I have one of those), and it id dead accurate!!! So I thought I'll try it in the Model AA. Turns out my speedometer is out to lunch. When it reads 35 MPH I'm actually going 50MPH. So I must have the high geared diff. I thought I was going faster than it read. Why is it out by 15MPH. Again running 6.50x20 all the round. As odd as that is this is good news, plenty of speed for me!!! Still chugs gas though, and I'm pretty sure the gas gauge is ok, but.........

[1931 flamingo]

If I remember correctly there were a few posts quite a while ago about improper length air adj screws?? I mention this as you say adjusting yours doesn't make much of a difference. Congrats on traveling 50MPH. That is a very nice looking truck.
Paul in CT

[Tom Wesenberg]

"Still chugs gas though, and I'm pretty sure the gas gauge is ok, but......... "

You need to slow down!

[columbiA]

Some air adj screws are two short & the spring will get coil bound before the screw is seated & you will not be able to get a proper idle mixture adj.If the screw is lightly seated & there is still space between the coils,then the screw length is OK. As for clubs,there is a model A & B club in Nanaimo & the VCCC(vintage car club of canada)has chapters inCowichan valley,Nanaimo,North island& Victoria.

[Bruce in southern OH]

Read 119 post to find out the speedometer was bad, you need to make this a TV show, great story, keep it up

[Double Trouble]

I thought I was going faster than it read. Why is it out by 15MPH.

Could it be the wrong speedometer gear set (the driven gear is stamped with the ratio) or just a bad speedometer?

[lookin-backtexas]

I enjoyed reading through all the posts with everyone trying to help determine why the truck wouldn't go faster than 25 mph and with all the fine tuning advice post after post, this should be required reading for any new Model A'er to learn how to diagnose problems - they will learn a lot of helpful info. Then at the end we find it's a faulty speedometer. Sort of the "Why won't my Model A start?" story and after multiple good Samaritan's advice of fiddle with this and fiddle with that, someone discovers they forgot to turn the gas on or key on. ha As a Model AA owner myself, if Kane couldn't tell the difference between going 25 and 50 in a AA, he must have some really good shocks! When I get mine up to 50 you really know it's hauling A _ _ and bounces all over the road.

[roblesterjr04]

Originally Posted by KANE MCAFFER

So my wife tells me about this application you can get on your iPhone. A speedometer. She says it works exactly accurate. I'm like ya right...... So I try it. I turn it on and go for a drive in our brand new mini van (don't tell anybody I have one of those), and it id dead accurate!!! So I thought I'll try it in the Model AA. Turns out my speedometer is out to lunch. When it reads 35 MPH I'm actually going 50MPH. So I must have the high geared diff. I thought I was going faster than it read. Why is it out by 15MPH. Again running 6.50x20 all the round. As odd as that is this is good news, plenty of speed for me!!! Still chugs gas though, and I'm pretty sure the gas gauge is ok, but.........

Way behind on reading all of this... but thats classic.

How did you make out in the end? Did you ever get her running like a top?