Noise in my new 29 a engin

[pinball73]

ok guys I am new at this, but hear we go! I have done a complete rebuild of my 1929 ford model a engine! it runs great sounds real good until I get it warmed up & on the highway in third gear at what I am going to call a cruse, 35 mph or so. not giving it any gas & not letting off of it either! I get a noise I don't like & don't think is normal! at this point I can retard the spark lever & it almost goes away! can't think it is spark knock ! it sounds too much like something mechanical! tried removing the plug wires one at a time & it makes no difference in the sound of the engine, so don't think it is rod,main, or piston! it has been bored 100 over new pistons, rings & valves have been re done. Babbitt is good & crank has been replaced. oil pressure is good, I would like more, but that is what they say it should have, thought pistons might be touching the head, so I scoped the cylinders & find no evidence of this happening! this thing has me barking at the moon! has any body got any ideas? I need help

[1crosscut]

Can you only hear the noise while in 3rd gear and going down the road after warm up or does it continue to make the noise while stopped after it is warmed up?
If the noise persists while stopped have you tried listening to the motor with a mechanics stethoscope to narrow the location down?

[Kurt in NJ]

How new is the engine, is it stock, or modified, retarding the spark is a way to quiet a loose bearing, did it always have the noise, or is it new and getting louder
louder cold or after hot?

[1930-Pickup]

Now you've done it! Welcome to the Barn!

[Big hammer]

Originally Posted by 1930-Pickup

Now you've done it! Welcome to the Barn!

X-2 wecome! It would help to know you location as someone could listen and guide you on the noise! Clubs in your area would be helpful also.

[Jacksonlll]

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It's really easy to forget to put in the plunger and spring in the timing gear cover.

[Bob C]

When you are running at 35mph where is the spark lever set?

Bob

[pinball73]

it is the loudest in 3 rd gear on the cruse! it will do it after it is warm at idle but not as bad! it gets quitter even at idle when you retard the timing

[pinball73]

I typically run it at full advance when at road speed, but when you retard the advance the noise quiets down, almost gone

[pinball73]

I put a new plunger & spring in to keep pressure on the cam!

[BILL WILLIAMSON]

"Possibly" loose flywheel bolts?
Pop off the starter & with a screwdriver in the flywheel teeth, see if it rotates back & forth an 1/8" or so.
Bill W.

[pinball73]

maybe 100 miles! it is stock other than being bored 100 over, plastic gaged all the bearings & they run from 1.5 too 2 ish, Babbitt is in real good condition. as I Sayed earlier, removing the plug wires one at a time makes no change in the sound of the engine. if it was a rod or piston I think it would show up on removing plug wires one at a time!

[pooch]

Get on a slight incline so the engine has to work in 3rd gear.

Retard spark lever until you feel a loss in power.

Advance it slightly, this is where you should be running at on the flat.

All you do with over advance is pound the babbit out.

The full window of advance is 40 degrees, dunno why Henry put that much in fer....

The engine sure don't like all of it.

[pinball73]

Bill I thought of that but I tightened them my self & put the safety wire in my self. I will look at this again because I am planning to remove the transmission & replace all the bearings & stop it from dripping oil this winter. this thing is about to get the best of me!

[Kohnke Rebabbitting]

Did you check rods for twist, Bend, and Off Set?

How much does the wrist pins have, for clearance.

Herm.

[denniskliesen]

Did you check the end play on your crankshaft? Did you check the backlash on your cam gear? Check the backlash on your rotor when the distributor is in the hole? What about the intermediate shaft between the oil pump drive and the distributor? Distributor shaft and sleeve? Check for wear in those areas. Take pictures.

[pinball73]

Pooch I will try that! what is the general thought on the automatic timing device that just does away with the spark control lever! timing is adjusted in accordance with engine rpm

[denniskliesen]

Originally Posted by pinball73

Pooch I will try that! what is the general thought on the automatic timing device that just does away with the spark control lever! timing is adjusted in accordance with engine rpm

They seem to have good results with a stock low compression head, have heard it does not work that well with a high compression head. You shouldn't ever need to go full advance on your spark lever.

[pinball73]

Kohnke did not check for twisted or bent rod, generally they all looked the same, laid out flat, but that is about as far as I went there. as for wrist pin clearance, the machine shop took care of all that I presume when they put in the new wrist pin bushings, they are supposed to be good & I trust them!

[pinball73]

denniskliesen! they are a bit pricy but I was wondering if it would be worth the investment? I am running pretty much stock

[pinball73]

dennisklisen cam & crank gears are in real good shape & seem to mash together real nice & not much if any slack. the distributer gear is in real good shape & I replaced the intermediate gear that runs oil pump & distributer. I actually did not check end play on crank shaft because the main had good Babbitt on the thrust washer, seems as though I had just a bit of end play in the crankshaft as I was messing with the fly wheal, not much as I can remember!

[pinball73]

hay guys how do I post a picture on hear? I like you guys to see what I have been working on!

[pinball73]

will get back at this tomorrow ! I just noticed it is past my bed time! thanks guys! later

[pinball73]

Kohnke! just reading your post again & got too wondering? is there offset built into the rods? or is this just something too look for that could be wrong?

[100IH]

The scoops on the rod caps need to have the open side face the camshaft. The caps should be matched to the rod by the stamped number, then the arrow on the piston, if there is one, points forward.

[katy]

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Originally Posted by pinball73

hay guys how do I post a picture on hear? I like you guys to see what I have been working on!

To post pictures, click on the Go advanced box, then click on the paper clip icon and you're in business. Simple.

[pinball73]

100ih! the pistons came from Snyder's & they had no marking on tem & the machine shop said that they would work either way! as for the rods & caps, I kept them together so I know that they match & I do have the dipper the right direction! I really think the GREMLINS have got me!

[Wm J.]

Post number 10 reminded me of when I bought a new plunger and spring I had a knock as you do and found the new spring was very weak. Put an original spring in and the knock was gone. Just a thought as the new springs may be stronger today.

[100IH]

With no arrow indicating front, it might not matter. On the mod. A, many were slotted on one skirt, those had to have the skirt oriented correctly. I don't remember which way, but if the machinist installed the rings and piston and rod assemblies he no doubt was familiar with the issue. I must add that I agree with the post about not advancing the spark to the full stop position. I go with just enough advance to get satisfactory performance, more is not better, just hard on the crank & bearings.

[larrys40]

pinball,

I see you're in northerm Missouri from your avarta. I'm down St. Louis way and I do Model A work. As Herm said it could be anything from a wrist pin to rod.... or something else internal. If there's someone near you that did the engine I would have them listen to it and see what their diagnosis was. Did they do the babbitt?
If you need additional help and diagnosis drop me a PM. We can chat and go from there.

Key at this point is carefull diagnosis without doing any further damage. Stuff happens so even with new pistons, etc things can go wrong. Good news is it can be fixed one way or another!
Larry Shepard

[700rpm]

Do not run with your spark fully advanced. You do not need an auto advance. Find the sweet spot for your engine and learn to drive it as it was designed. Most times, if the car is timed right, your spark lever at about 9:00 should be fine for cruising.

[George Miller]

Originally Posted by Kohnke Rebabbitting

Did you check rods for twist, Bend, and Off Set?

How much does the wrist pins have, for clearance.

Herm.

That could be it.

[Railcarmover]

I've got a few questions...

how does a higher compression head alter the operation of a gyro style advance on the distributor shaft?


How can you effectively measure the optimum 10 degrees of timing for each 1000 rpm with a quadrant lever?

If too much timing advance causes center main bearing failure and the highest load on the engine is during acceleration how can you effectively advance the spark manually during acceleration without going into the 'danger' zone?

why did Ford immediately use mechanical flyweight timing advance in model B distributor along with the host of other design revisions with the model B?

[Kohnke Rebabbitting]

Originally Posted by pinball73

Kohnke! just reading your post again & got too wondering? is there offset built into the rods? or is this just something too look for that could be wrong?

No Mr. Pinball, there should be NO off set in the Rods.

Wrist pins should not have less then .000-03 to not over .000-50 tenths of a thousandths clearance.

Herm.

[Barry B./ Ma.]

I had one of those, after rebuilding everything sounded great but after 1000 miles it started to overheat going through the mountains then that little noise started , it seemed to go away under slight power and was most noticeable under no power or float. I changed a lot of stuff but never really found the source, I was left with the belief that it was the cam gear, had the engine apart and could see that the tops of a couple pistons had hit the gasket but after getting it back together the noise was still there, however the noise only started after the engine ran a mile or so so I left well enough alone and it never got any worse.

[pinball73]

Barry B. if you ever find out what the problem is, please let me know! it sounds as though we have just about the same problem! the part that gets me is when I retard the spark the noise quiets down, almost goes away, not completely, but almost I get a bit of noise when I rev the engine, but not as loud as when at road speed

[pinball73]

Kohnke wrist pins came new with pistons! put new wrist pin bushings in the rods & they were honed to very snug fit, I double checked the pin keepers to make certain they were locked in place!

[Railcarmover]

Originally Posted by pinball73

denniskliesen! they are a bit pricy but I was wondering if it would be worth the investment? I am running pretty much stock

From all the threads I've read the automatic timing advance works nicely.the only caveat is the curve isn't broad enough, easily solved by keeping your manual spark control hooked up but limited in travel to move the entire curve up and down with the lever.To set it up correctly requires peak advance timing,basically running the engine at high rpm and using a timing light and pointer to check that max advance does not exceed 30 degrees, then setting your lever limit to stop at that point..this allows you to retard the spark by hand if the condition requires it, yet never allow you to exceed max advance.

the benefit to automatic advance is correct timing during acceleration, a key to long center main bearing life...and instead of not being recommended, its a must for using a high compression head, due to the compression increase,the 'hammer effect' on the center main bearing during detonation caused by improper timing being greater than stock compression,higher compression accentuates the detonation effect.

[Simonpie]

Originally Posted by Railcarmover

I've got a few questions...

how does a higher compression head alter the operation of a gyro style advance on the distributor shaft?


How can you effectively measure the optimum 10 degrees of timing for each 1000 rpm with a quadrant lever?

Railcarmover, The head doesn't change the timing. The head changes the engine's need for certain timing. Generally, higher compression causes higher peak temp on compression just before ignition. This causes a faster burn, so the engine needs less ignition advance. A similar effect can happen with a cam, manifold, or exhaust change. Different cylinder filling at different rpm's makes the burn rate different, so different ignition timing may be needed.

The only way I know to measure a bob weight type advance at different rpm's is with a tachometer and a timing light.

[harryc]

I don't know if anybody mentioned it but it could be a loose timing gear--loose on the cam. I once had a knock that was driving me crazy and even though I was sure the timing gear was tight when I checked it I found it loose. When I tightened it and center punched the nut to make sure it wouldn't loosen the knock was gone. And in my case it only knocked after the engine had warmed.

[Railcarmover]

Originally Posted by Simonpie

Railcarmover, The head doesn't change the timing. The head changes the engine's need for certain timing. Generally, higher compression causes higher peak temp on compression just before ignition. This causes a faster burn, so the engine needs less ignition advance. A similar effect can happen with a cam, manifold, or exhaust change. Different cylinder filling at different rpm's makes the burn rate different, so different ignition timing may be needed.

The only way I know to measure a bob weight type advance at different rpm's is with a tachometer and a timing light.

My point in question brother...how can you effectively monitor the changes needed in timing with a lever? and why? especially given a center main expected to handle the impulse from four cylinders with no more area than a front bearing that handles two cylinders? regardless of timing required by a raise in compression, the basic need for a mechanical ramped increase in timing is critical for engine life as a whole. Harold Hicks,the ford engineer brought in from aircraft design to raise the hp to 40 noticed a main bearing weakness with the design...but was shot down by Mr Ford,who allowed his redesign of the exhaust manifold and additional cooling around the exhaust valves,but felt the three main bearing design was adequate..but he nodded with the B engine,offering mechanical advance from the jump...and a counterbalanced crank...

[pinball73]

Harryc! this food for thought! when I change the spark lever it would basically, in a round about way put more load on the cam in advance & less in retard! this would cause the noise too change, will need too think this one out! thanks

[pinball73]

I think if & when I go back into the engine I will install the automatic timing advance system, for two reasons. it would regulate the timing that was needed by the engine when it needed it! it would also eliminate the chance of mistakenly advancing the timing too much & beating on the Babbitt in the rods & mains.

[100IH]

I don't know about "eliminating the chance of" . When you go to the automatic timing gismo, you still have to do the dance of where is the timing at idle and high speed with no regard for load on acceleration and climbing a hill. The first thing I would check if I were there is; the starting point at idle, Very Slow and not much power. After that, you have about 30-32 deg. to work with which is about 1/2 way down on the lever, maybe 2/3.

[pinball73]

got a silly question? what are the dimensions of a 1929 model a radiator? it is hard to get a accurate measurement while it is on the car with the shroud & all!

[pinball73]

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well I probably found a lot of my noise! was planning on rebuilding the transmission this winter, so I got started on it a few days ago! took the top shift tower off & felt pretty good on what I am seeing! got the transmission out & apart & found the u-joint is toast! I have never seen one worn as bad as this one. the next thing I find is you can slide the u-joint forward & back just about 1/2"! who ever was the last one was that was in there had put a oversized lock washer & a soft iron flat washer to hold the u-joint on the out put gear! I have no idea how it even stayed on there, the washer was bent back enough I could almost remove the u-joint without removing the bolt! not quite but almost. can't weight to get it to gather & see what changes!

[Benson]

Hey Pinball,

Here is what happened to me ... might help you out.

06-03-2017, 01:14 PM #3


________________________________________
My coupe suddenly started to make noise in 2nd gear about 5000 miles after a complete rebuild. All new shafts, all new Mark gears, bearings and etc.

Looking back on it the only thing NOT replaced were the three needle bearings because they looked good. (HINT ... HINT)

I lived with the noise by keeping speeds low in 2nd gear and drove another 5000 miles.

Finally got tired of noise and tore it down.

Found that one of the needle bearings inside the cluster gear had come apart so one end of cluster gear was "flopping around".

Second/third slider gear and the corresponding gear on the cluster were "all chewed up".

These were brand new Mark USA gears!

I wonder if maybe I could have saved the 2nd gear and cluster by taking it apart as soon as the noise started! Your call !!

Steve at Bert's said it was the noisiest transmission that he had ever heard.

On the surviving needle bearings you can see that the needles are worn to "Points" where they fit into the holes in the "cage". Other wise the bearings look new.
________________________________________
Last edited by Benson; 06-03-2017 at 01:28 PM.

Originally Posted by pinball73

well I probably found a lot of my noise! was planning on rebuilding the transmission this winter, so I got started on it a few days ago! took the top shift tower off & felt pretty good on what I am seeing! got the transmission out & apart & found the u-joint is toast! I have never seen one worn as bad as this one. the next thing I find is you can slide the u-joint forward & back just about 1/2"! who ever was the last one was that was in there had put a oversized lock washer & a soft iron flat washer to hold the u-joint on the out put gear! I have no idea how it even stayed on there, the washer was bent back enough I could almost remove the u-joint without removing the bolt! not quite but almost. can't weight to get it to gather & see what changes!

[Kohnke Rebabbitting]

Originally Posted by pinball73

Kohnke did not check for twisted or bent rod, generally they all looked the same, laid out flat, but that is about as far as I went there. as for wrist pin clearance, the machine shop took care of all that I presume when they put in the new wrist pin bushings, they are supposed to be good & I trust them!

You can't tell by looking at rods and see if there out of alignment, they have to be put on a Rod Aligner, to check for twist, bend, and off set.

As far as wrist pins go, any movement that can be felt, is no good. The clearance should be right on at .005.

Hope you find the problem.

Herm.

[Tom Wesenberg]

I know Herm meant .0005"

[Chuck Sea/Tac]

Originally Posted by pinball73

well I probably found a lot of my noise! was planning on rebuilding the transmission this winter, so I got started on it a few days ago! took the top shift tower off & felt pretty good on what I am seeing! got the transmission out & apart & found the u-joint is toast! I have never seen one worn as bad as this one. the next thing I find is you can slide the u-joint forward & back just about 1/2"! who ever was the last one was that was in there had put a oversized lock washer & a soft iron flat washer to hold the u-joint on the out put gear! I have no idea how it even stayed on there, the washer was bent back enough I could almost remove the u-joint without removing the bolt! not quite but almost. can't weight to get it to gather & see what changes!

In your first post, you mentioned removing the spark wires one at a time, however that didn’t change the sound of the engine. Was the “sound” there when you weren’t moving? If so, then it seems like a second problem, other than a bad u joint. ???

[goodcar]

Originally Posted by pinball73

ok guys I am new at this, but hear we go! I have done a complete rebuild of my 1929 ford model a engine! it runs great sounds real good until I get it warmed up & on the highway in third gear at what I am going to call a cruse, 35 mph or so. not giving it any gas & not letting off of it either! I get a noise I don't like & don't think is normal! at this point I can retard the spark lever & it almost goes away! can't think it is spark knock ! it sounds too much like something mechanical! tried removing the plug wires one at a time & it makes no difference in the sound of the engine, so don't think it is rod,main, or piston! it has been bored 100 over new pistons, rings & valves have been re done. Babbitt is good & crank has been replaced. oil pressure is good, I would like more, but that is what they say it should have, thought pistons might be touching the head, so I scoped the cylinders & find no evidence of this happening! this thing has me barking at the moon! has any body got any ideas? I need help

Another possibility is loose center cam journal. Might need to add cam bearings.

[pinball73]

well, problem fixed I think! all new bearings in the transmission, new input shaft, replaced the cluster gear & second & high sliding gear, new cluster & reverse idler pins & a new u-joint! while doing all of this I also found the bracket that bolts the alternator too the block was loose & it had to be making noise! have not had it in the road yet, but pretty shore the noise is gone

[pinball73]

got a question! I filled the transmission with Lucas gear additive, only! I was told that every one uses STP! the Lucas is about the viscosity as the STP, but it will not foam & it sticks to the gears better. what does every body think about doing this?

[100IH]

STP is not a lubricant it is an additive and so is Lucas. So, do two modifiers make a lubricant, not likely. Today's equivalent of 600 W is known as Steam Cylinder Oil and you will only find it at the local distributor, not at the auto parts store. Do a search here for "600 W". Remember, when your back on the road with your ears on, the consensus on timing was NOT all the way down. That is the sound of the engine crying and saying; back off, that's too much.

[Fred K-OR]

Most of the vendors carry 600 W oil.

[eagle]

Lucas oil stabilizer works great as transmission grease. Shifts smooth as silk. Much better than the 600W oil I got from a vendor.

[CT Jack]

It could be a loose timing gear nut. A simple test is to insert timing pin into timing hole while the engine is running at idle speed. Slowly push pin against gear if the noise goes away it means either the nut is loose or the gear is worn. Sometimes a worn 2 piece gear will produce this type of noise.