The Ford Barn

Old2New · 10-15-2016, 12:53 PM

Hi guys, I just aquired a 1968 galaxie 500 with the original 390 2bbl, c6 automatic. It runs pretty well when its at an idle in neutral but when I put it in drive or reverse it stumbles and dies. This is the way it has ran since I got it, it didnt just start happening. I am able to drive it if I ride the brake at a stop and accelerate. If I put it in gear and gas it immediately, It will catch up and then maintain an idle but VERY rough and on what sounds like 6 cylinders. This has been my go at fixing it.

IGNITION: First thing I did was replace the spark plugs. When I pulled the old ones they were not in bad shape but very wet with gas. All of them. No oil, just gas. Then I replaced the wires, coil, point and condenser and set the timing to 8 degrees btdc with the advance capped off. Found out that the advance had a leak so that was replaced as well. Vacuum off of ported. Still not fixed.

CARBURETOR: Original Autolite 2100, 1.23. When I first took the carb of the bowl was filled with nasty orange sludge. I chem dipped the carb and replaced all the gaskets, power valve, accelerator pump needle and seat, float was brass and good. New fuel filter. Still runs the same.

VACUUM AND AIR LEAKS: I took a cigar and blew smoke into the intake and there are no vacuum leaks that I can see. Vacuum gauge reads 21 and steady.

TRANSMISSION: It is a c6 that shifts like butter when driving. I think it needs a new modulator. It runs off of a t at the intake manifold and I think the modulatormis ruptured because it has some tranny fluid it the t fitting. Could it be pulling enough tranny fluid into the intake to cause it to misfire?

VALVES: Pulled the valve covers and they are non adjustable. All the "rocker rail bolts" were tightned to 43 ft lbs. Dont know what they are really called.

STILL NEED TO DO A COMPRESSION TEST! Just moved so Im tapped out until friday so I cant buy one yet. My friend thinks my valves are swiss cheese. I have not pulled the heads yet... Im trying to do the little things first. Could this be a blown head gasket, worn timing chain, slipped chain? I was able to set the timing. Dont know now and Im at a loss for ideas other than tearing down. Want to avoid doing that until tax season when I can fix it with SPEED PARTS!!! woohoo

dmsfrr · 10-15-2016, 02:34 PM

I'd think if the intake valves were leaking the vacuum would be lower and/or jumpy.

Starting fluid or something like it might work better looking for vacuum leaks around the intake manif, but if you've got a bigger one the vacuum wouldn't be so good (21psi).
Maybe a small leak under the dash if the car has vac. controlled heater & AC vents?

Compression test is a good idea and I wouldn't even consider pulling the heads unless the readings are bad.

Vacuum modulator? Maybe that's it, and if it's bad it sure couldn't help, but I know nothing about them.

Timing chain? Yes it could be loose but that shouldn't affect the running of the engine in this way.
If it had slipped you'd be picking pieces of the engine out of the pan or up off the road.

.

Alaska Jim · 10-15-2016, 03:58 PM

use a propane bottle and a length of hose to check for vac. leaks. use of berrymans chemtool, and other spray liquids can take off paint and also has a chance of igniting a fire. direct the hose with propane directly where the vac. leak is suspected. ( keep away from exhaust ). if there is a leak , there will be a noticeable increase in rpm. usually if the vac. modulator is leaking vac. there will be an erratic shifting of the trans. it can however leak and have fluid drawn into the intake and not affect trans shifting. make sure that the spark plug wire are in the correct firing order. Did you replace the dist. cap? I have had this same problem with a cap that had a hair line crack. It also could have " carbon tracking " on the inside of the cap causing the misfire/rough run condition. check your fuel filter again, to see if it is plugged , try blowing through it. it is possible that there is crap in your tank, and is bad enough to quickly plug a filter depending on what type you have. hope that this can be of some help. I forgot to ask if when you had the valve covers off, if you checked for bent push rods. It is also possible that the coil is breaking down, and although it is a long shot, just because that condenser is new , does not make it "good" . a lot of them are made off-shore these days and the quality is poor. try to find parts made in the USA if possible.------Jim

Ole Don · 10-16-2016, 08:00 AM

Check where the wire goes into the dizzy to the points. When the points plate moves, the wire can break inside the insulation, and the wire still looks good. Set up a test light, and manually move the advance and watch the light.

Ford blue blood · 10-16-2016, 08:33 AM

Clamp off the vacuum line to the booster. Might have a problem when the brake pedal is depressed.

dmsfrr · 10-16-2016, 07:46 PM

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Quote:

Originally Posted by Ole Don

Check where the wire goes into the dizzy to the points. When the points plate moves, the wire can break inside the insulation, and the wire still looks good. Set up a test light, and manually move the advance and watch the light.

The points should have a ground wire too. It can do the same thing, if it's bad so's your ignition.
.

wbedwards · 10-16-2016, 09:59 PM

I'm leaning towards a bad power valve or missing gasket on it. When idling, can you look down the carb and see if fuel is dripping instead of vaporizing? While in there recheck the idle circuit and make sure nothing is amiss.
I would replace the vacuum modulator before trying to run it again although it seems like that would make it run lean and not shift into forward or reverse.

good luck with the detective work

bobss396 · 10-18-2016, 03:39 PM

Does the carb have an anti-stall dashpot on it? I've had that happen on a couple of my Galaxies.

Clamp or cap off any vacuum lines including your suspect modulator and see what happens. But it does sound vacuum related.

Alaska Jim · 10-18-2016, 07:47 PM

fordblueblood may be on the right track. I have seen this problem with a powerbrake booster before, although it is not very common. what happens is that the rubber diaphragm's in the brake booster deteriorate and get a crack or hole in them. when I worked for the local GM dealership back in the '70's I rebuilt several of them. pain in the butt. special tools needed and it is clumsy

Old2New · 10-20-2016, 10:11 AM

Thanks for all the late replies. I was in the middle of moving and ended up having to tow it, oh well. So a few people to respond to...
●First thing is it does not have a bake booster so that can't be the source of the leak.
●The vacuum modulator was replaced.
●I remember checking the ground wire in the dizzy and its old and nasty looking. Its a crusty brown wire that has no insulation on it? Is that original?
●The power valve has a gasket on it. It ran rough like this before and after the carburetor rebuild...

I brought a buddy over and he tried a few things. When it was at full operating temp, he completely choked off the carb and it kept running, barely, but it maintained an idle. Definately a vacuum leak. The most interesting thing was he sprayed electric parts cleaner into the carb while it was running and it actually smoothed out the idle! Whats most interesting is about 3 seconds after spraying the carburetor, massive clouds of the electric parts cleaner came out the tail pipe! Burned the hell out of my lungs. Does that mean an exhaust valve is not closing? My buddie thinks the valves are bad?

dmsfrr · 10-20-2016, 12:14 PM

Quote:

Originally Posted by Old2New

●I remember checking the ground wire in the dizzy and its old and nasty looking. Its a crusty brown wire that has no insulation on it? Is that original?

It's not your biggest problem so I'll answer and then get out of the way.

No insulation can be normal, they're made either way, crusty & nasty looking is not.
Replacing it won't hurt and will keep it from falling apart on you later, at a worse time.

Dobie Gillis · 10-20-2016, 03:08 PM

Torque converter?

bobss396 · 10-21-2016, 08:44 AM

The carb could still have an internal vacuum leak. How clean was the carb flange, any pitting? I always file them smooth when I change the gasket. I would carefully spray carb cleaner around the base of the carb with it running.

Alaska Jim · 10-21-2016, 10:03 AM

the reason the idle smoothed out when you sprayed it, is because with a vac. leak it is running lean, when the cleaner is introduced it made the feul mixture richer, just the same as if you would have closed the choke a little, or covering the top of the carb with your hand.

bobss396 · 10-21-2016, 12:02 PM

Quote:

Originally Posted by Alaska Jim

the reason the idle smoothed out when you sprayed it, is because with a vac. leak it is running lean, when the cleaner is introduced it made the feul mixture richer, just the same as if you would have closed the choke a little, or covering the top of the carb with your hand.

In total agreement with this. It was an instant cure all for the problem. If you haven't encountered many vacuum leaks, they can be elusive and take time to find. I'm sure that there are more than a few of us here that could find the source in about 5 minutes.

Old2New · 10-21-2016, 01:29 PM

Quote:

Originally Posted by Alaska Jim

the reason the idle smoothed out when you sprayed it, is because with a vac. leak it is running lean, when the cleaner is introduced it made the feul mixture richer, just the same as if you would have closed the choke a little, or covering the top of the carb with your hand.

Well my buddy next door sprayed it in his and it almost died? Was that because it flooded a bit?

I didn't think to check the flange for smoothness. I didn't see any pitting though. I have sprayed ether all around the carb and no throttle change. Im going to try to pull the heads today. I have never done that. Anything I should know before I do? I don't plan to put it rignt back together. Is the engine safe from rust apart like that? should I coat with oil kr stuff towels down the holes? Haha I just dont know.

Alaska Jim · 10-21-2016, 05:57 PM

If to much is sprayed at one time or the leak is relatively small, yes it can make the eng. almost die, and sometimes it will if to much is sprayed. it is possible that the intake manifold has a vac. leak. I have also encountered an intake that leaked from the bottom side ( bad intake gasket, and sucking air from the valley area ) although it is not very common. I would search further before pulling the heads. do a compression ck. if your compression is good and all cyl. are pretty close ( within 10psi of each other ) you are wasting your time and money in pulling the heads in my opinion. If you have not pulled a set of heads before , get some help from someone who has a little experience. it is easy to take things apart, but putting it back together correctly can be a bit trickier. not saying you are not capable, it would just be better to have someone with some experience to help and make things easier. no matter what you decide, if you take it apart get a manual for the vehicle that shows the correct procedure for disassembly and reassembly. maybe take some pictures to help remember where things go. just trying to help.

dmsfrr · 10-21-2016, 06:20 PM

Quote:

Originally Posted by Alaska Jim

I would search further before pulling the heads. do a compression ck. if your compression is good and all cyl. are pretty close ( within 10psi of each other ) you are wasting your time and money in pulling the heads in my opinion.

Times 2

Old2New · 10-21-2016, 09:27 PM

Thanks for the warning guys. I have seen so many engines apart and out of cars being sold on craigslist, probably because they realised they were in over their heads. Do you guys reccomend haynes or chiltons? I had a guy tell me chiltons are more technical where as haynes are more real world? I am very detail oriented and research for as long as I need to be 100% on what I am doing. Youtube also helps tremendously. Not to mention awesome people like all of you who take time out of your schedule to help someone like me.
I wonder how much money you all have saved people over the years just from your help on here. Including me. I can't thank you all enough.

40cpe · 10-21-2016, 09:51 PM

If spraying ether around the carb doesn't change things, but spraying it IN the carb does smooth it out, it could very well be an intake gasket leak. I agree with those asking for a compression test. Valves leaking badly enough to make it run bad will not give good compression readings. If all efforts fail, pull the intake and check the gaskets. Be ready, that thing is HEAVY.

10-15-2016, 12:53 PM	#1
Old2New Member Join Date: Aug 2016 Location: Mcminnville, OR Posts: 66	390 stumbles, misses and dies in gear Hi guys, I just aquired a 1968 galaxie 500 with the original 390 2bbl, c6 automatic. It runs pretty well when its at an idle in neutral but when I put it in drive or reverse it stumbles and dies. This is the way it has ran since I got it, it didnt just start happening. I am able to drive it if I ride the brake at a stop and accelerate. If I put it in gear and gas it immediately, It will catch up and then maintain an idle but VERY rough and on what sounds like 6 cylinders. This has been my go at fixing it. IGNITION: First thing I did was replace the spark plugs. When I pulled the old ones they were not in bad shape but very wet with gas. All of them. No oil, just gas. Then I replaced the wires, coil, point and condenser and set the timing to 8 degrees btdc with the advance capped off. Found out that the advance had a leak so that was replaced as well. Vacuum off of ported. Still not fixed. CARBURETOR: Original Autolite 2100, 1.23. When I first took the carb of the bowl was filled with nasty orange sludge. I chem dipped the carb and replaced all the gaskets, power valve, accelerator pump needle and seat, float was brass and good. New fuel filter. Still runs the same. VACUUM AND AIR LEAKS: I took a cigar and blew smoke into the intake and there are no vacuum leaks that I can see. Vacuum gauge reads 21 and steady. TRANSMISSION: It is a c6 that shifts like butter when driving. I think it needs a new modulator. It runs off of a t at the intake manifold and I think the modulatormis ruptured because it has some tranny fluid it the t fitting. Could it be pulling enough tranny fluid into the intake to cause it to misfire? VALVES: Pulled the valve covers and they are non adjustable. All the "rocker rail bolts" were tightned to 43 ft lbs. Dont know what they are really called. STILL NEED TO DO A COMPRESSION TEST! Just moved so Im tapped out until friday so I cant buy one yet. My friend thinks my valves are swiss cheese. I have not pulled the heads yet... Im trying to do the little things first. Could this be a blown head gasket, worn timing chain, slipped chain? I was able to set the timing. Dont know now and Im at a loss for ideas other than tearing down. Want to avoid doing that until tax season when I can fix it with SPEED PARTS!!! woohoo

10-15-2016, 02:34 PM	#2
dmsfrr Senior Member Join Date: Aug 2012 Location: Abq, NM Posts: 3,607	Re: 390 stumbles, misses and dies in gear I'd think if the intake valves were leaking the vacuum would be lower and/or jumpy. Starting fluid or something like it might work better looking for vacuum leaks around the intake manif, but if you've got a bigger one the vacuum wouldn't be so good (21psi). Maybe a small leak under the dash if the car has vac. controlled heater & AC vents? Compression test is a good idea and I wouldn't even consider pulling the heads unless the readings are bad. Vacuum modulator? Maybe that's it, and if it's bad it sure couldn't help, but I know nothing about them. Timing chain? Yes it could be loose but that shouldn't affect the running of the engine in this way. If it had slipped you'd be picking pieces of the engine out of the pan or up off the road. .

10-15-2016, 03:58 PM	#3
Alaska Jim Senior Member Join Date: May 2010 Location: Palmer, Alaska Posts: 1,575	Re: 390 stumbles, misses and dies in gear use a propane bottle and a length of hose to check for vac. leaks. use of berrymans chemtool, and other spray liquids can take off paint and also has a chance of igniting a fire. direct the hose with propane directly where the vac. leak is suspected. ( keep away from exhaust ). if there is a leak , there will be a noticeable increase in rpm. usually if the vac. modulator is leaking vac. there will be an erratic shifting of the trans. it can however leak and have fluid drawn into the intake and not affect trans shifting. make sure that the spark plug wire are in the correct firing order. Did you replace the dist. cap? I have had this same problem with a cap that had a hair line crack. It also could have " carbon tracking " on the inside of the cap causing the misfire/rough run condition. check your fuel filter again, to see if it is plugged , try blowing through it. it is possible that there is crap in your tank, and is bad enough to quickly plug a filter depending on what type you have. hope that this can be of some help. I forgot to ask if when you had the valve covers off, if you checked for bent push rods. It is also possible that the coil is breaking down, and although it is a long shot, just because that condenser is new , does not make it "good" . a lot of them are made off-shore these days and the quality is poor. try to find parts made in the USA if possible.------Jim Last edited by Alaska Jim; 10-15-2016 at 04:04 PM.

10-16-2016, 08:00 AM	#4
Ole Don Senior Member Join Date: May 2010 Location: St. Michael, Minnesota Posts: 1,713	Re: 390 stumbles, misses and dies in gear Check where the wire goes into the dizzy to the points. When the points plate moves, the wire can break inside the insulation, and the wire still looks good. Set up a test light, and manually move the advance and watch the light.

10-16-2016, 08:33 AM	#5
Ford blue blood Senior Member Join Date: Jul 2011 Location: Birmingham, AL Posts: 814	Re: 390 stumbles, misses and dies in gear Clamp off the vacuum line to the booster. Might have a problem when the brake pedal is depressed. __________________ Bill, certified Ford nut. 2016 F-150 2016 Focus 08 Shelby GT500 57 Ford Ranchero 36 Chevy, 351C/FMX, 8", Mustang II

10-16-2016, 09:59 PM	#7
wbedwards Senior Member Join Date: Jan 2015 Location: Birmingham, Al. Posts: 339	Re: 390 stumbles, misses and dies in gear I'm leaning towards a bad power valve or missing gasket on it. When idling, can you look down the carb and see if fuel is dripping instead of vaporizing? While in there recheck the idle circuit and make sure nothing is amiss. I would replace the vacuum modulator before trying to run it again although it seems like that would make it run lean and not shift into forward or reverse. good luck with the detective work

10-18-2016, 03:39 PM	#8
bobss396 Senior Member Join Date: Aug 2014 Posts: 721	Re: 390 stumbles, misses and dies in gear Does the carb have an anti-stall dashpot on it? I've had that happen on a couple of my Galaxies. Clamp or cap off any vacuum lines including your suspect modulator and see what happens. But it does sound vacuum related.

10-18-2016, 07:47 PM	#9
Alaska Jim Senior Member Join Date: May 2010 Location: Palmer, Alaska Posts: 1,575	Re: 390 stumbles, misses and dies in gear fordblueblood may be on the right track. I have seen this problem with a powerbrake booster before, although it is not very common. what happens is that the rubber diaphragm's in the brake booster deteriorate and get a crack or hole in them. when I worked for the local GM dealership back in the '70's I rebuilt several of them. pain in the butt. special tools needed and it is clumsy

10-20-2016, 10:11 AM	#10
Old2New Member Join Date: Aug 2016 Location: Mcminnville, OR Posts: 66	Re: 390 stumbles, misses and dies in gear Thanks for all the late replies. I was in the middle of moving and ended up having to tow it, oh well. So a few people to respond to... ●First thing is it does not have a bake booster so that can't be the source of the leak. ●The vacuum modulator was replaced. ●I remember checking the ground wire in the dizzy and its old and nasty looking. Its a crusty brown wire that has no insulation on it? Is that original? ●The power valve has a gasket on it. It ran rough like this before and after the carburetor rebuild... I brought a buddy over and he tried a few things. When it was at full operating temp, he completely choked off the carb and it kept running, barely, but it maintained an idle. Definately a vacuum leak. The most interesting thing was he sprayed electric parts cleaner into the carb while it was running and it actually smoothed out the idle! Whats most interesting is about 3 seconds after spraying the carburetor, massive clouds of the electric parts cleaner came out the tail pipe! Burned the hell out of my lungs. Does that mean an exhaust valve is not closing? My buddie thinks the valves are bad? Last edited by Old2New; 10-20-2016 at 10:28 AM.

10-20-2016, 03:08 PM	#12
Dobie Gillis Senior Member Join Date: May 2012 Location: Middle TN Posts: 1,060	Re: 390 stumbles, misses and dies in gear Torque converter?

10-21-2016, 08:44 AM	#13
bobss396 Senior Member Join Date: Aug 2014 Posts: 721	Re: 390 stumbles, misses and dies in gear The carb could still have an internal vacuum leak. How clean was the carb flange, any pitting? I always file them smooth when I change the gasket. I would carefully spray carb cleaner around the base of the carb with it running.

10-21-2016, 10:03 AM	#14
Alaska Jim Senior Member Join Date: May 2010 Location: Palmer, Alaska Posts: 1,575	Re: 390 stumbles, misses and dies in gear the reason the idle smoothed out when you sprayed it, is because with a vac. leak it is running lean, when the cleaner is introduced it made the feul mixture richer, just the same as if you would have closed the choke a little, or covering the top of the carb with your hand.

10-21-2016, 05:57 PM	#17
Alaska Jim Senior Member Join Date: May 2010 Location: Palmer, Alaska Posts: 1,575	Re: 390 stumbles, misses and dies in gear If to much is sprayed at one time or the leak is relatively small, yes it can make the eng. almost die, and sometimes it will if to much is sprayed. it is possible that the intake manifold has a vac. leak. I have also encountered an intake that leaked from the bottom side ( bad intake gasket, and sucking air from the valley area ) although it is not very common. I would search further before pulling the heads. do a compression ck. if your compression is good and all cyl. are pretty close ( within 10psi of each other ) you are wasting your time and money in pulling the heads in my opinion. If you have not pulled a set of heads before , get some help from someone who has a little experience. it is easy to take things apart, but putting it back together correctly can be a bit trickier. not saying you are not capable, it would just be better to have someone with some experience to help and make things easier. no matter what you decide, if you take it apart get a manual for the vehicle that shows the correct procedure for disassembly and reassembly. maybe take some pictures to help remember where things go. just trying to help.

10-21-2016, 09:27 PM	#19
Old2New Member Join Date: Aug 2016 Location: Mcminnville, OR Posts: 66	Re: 390 stumbles, misses and dies in gear Thanks for the warning guys. I have seen so many engines apart and out of cars being sold on craigslist, probably because they realised they were in over their heads. Do you guys reccomend haynes or chiltons? I had a guy tell me chiltons are more technical where as haynes are more real world? I am very detail oriented and research for as long as I need to be 100% on what I am doing. Youtube also helps tremendously. Not to mention awesome people like all of you who take time out of your schedule to help someone like me. I wonder how much money you all have saved people over the years just from your help on here. Including me. I can't thank you all enough.

10-21-2016, 09:51 PM	#20
40cpe Senior Member Join Date: May 2010 Location: Star, MS Posts: 4,024	Re: 390 stumbles, misses and dies in gear If spraying ether around the carb doesn't change things, but spraying it IN the carb does smooth it out, it could very well be an intake gasket leak. I agree with those asking for a compression test. Valves leaking badly enough to make it run bad will not give good compression readings. If all efforts fail, pull the intake and check the gaskets. Be ready, that thing is HEAVY.