Hey guys,

First time back in a while, finally getting nice here in New England. I bought my 67 GTX at a small classic car dealer a couple hours away. It looks great and is very stock original, auto trans, as far as I know matching numbers, I can certainly tell he engine is at least date code correct. (HP C 440 stamp on top front) Anyways, the day I bought it, I was on the highway home, stopped for gas and it was stalling at idle in Drive, as in slowly driving up to a gas pump, it stalls. By this point, the car was hot (not overheating, good temp but very much warmed up) When restarting, it cranks for a while before it starts, and then you have to keep the rpms up to keep it going. I didn't think it was an issue because I have a trusted mechanic at home and figured I'd have him look at it, adjust and I'd be all set. I took it to him, he adjusted the carb (original Carter AFB) and sent me on my way. Again, once it got hot, stalling like crazy at slow parking lot trolling speeds. I took it back to the mechanic, he said the carb is really bad and that he noticed an electrical line labeled "choke", which tells him the guy that traded it in took off a newer electric choke carb and put this old one back on before trading it.... Its been rebuilt and should be replaced with an Edelbrock to make life much better. I'm fine with that, so I bought an Eddy 850 and he installed it. It ran MUCH better (and faster!) cold, but still, once it gets hot, it stalls like a **** at slow speeds. It was the end of the season, so I waited til after the winter and took it back to him this week. He verbally told me it sounded like from what I was describing that it might be running lean. Okay, he kept it for a day, checked the plugs and claims they were "perfectly tan" so he was not convinced it was lean. He ran some tests on meters and told me he saw no valve or compression issues evident, it "runs strong". He actually changed the springs in the carb to lean it out more because he thought maybe the vaccuum was low and the springs were too hard for the carb to open. He also adjusted the timing. I took it home, ran great while cool, but again, stalling when hot after about 30 mins of driving.
I've had my mechanic for several years. He's a guy in his 50s with classic cars of his own and always cool to go to his shop cuz he always has many classic muscle cars he's fixing for people. He's a great mechanic. I truly believe that and he rebuilt my 67 Mustang and made it sing and dance. I know he knows his stuff. If anything, he tries like hell to fix things the easiest way before digging real deep and diagnosing as a more major problem. In other words, he doesn't like to do major surgery before fixing it the most easy way first. I am geting the feeling that there may be something more of an issue here. When I bought the car, it was described as just having an engine rebuild with a new slightly hotter purple cam but SUPPOSEDLY still standard bore.

What COULD be the issue here? Could I be looking at something major in this engine, and if so, what are some things that it could possibly be. Or is this common trial and error adjusting timing and the carb jets etc. It just awfully weird that even a new carb had no impact on this issue and it still stalls exactly like the day I bought the car with an original, banged up old carb.

Thanks in advance and sorry for the long winded post on something so lame...

 

welcome back
does the car have pointas of electronic ignition?
sounds like it is either carb. or ignition related

 

Its got an electronic conversion....pertronix I believe...

 

http://www.youtube.com/watch?v=NZU3ckWpCdc

 

But, there's nothing funny about vapor lock. It's the third most common cause of stalling. So please, take care of your car and get it ...

 

id say vapor lock too

 

I am no pro mechanic, but I know this much, it takes fuel, air and fire to make the car run. Perhaps you need to make more fuel available in the idle circut and turn up te idle a bit. Make sure the engine can breathe, is the air filter clean? Then maybe check that you have a good coil and that your battery is getting fully charged.

Good luck!

 

phenolic carb spacer, make sure the fuel line is routed away from high heat areas...

 

How's the timing ?

 

What size thickness carb spacer? Anyone better than the other? I have the stock air cleaner on this car and its tight under the hood as is...thanks for the input! Open or the 4 hole type?

 

have you tried re-adjusting the carb. yourself?

 

It's unusual for a car to overheat due to carburetor issues, more than likely the problem lies somewhere else. If your car is an automatic, check and make sure the transmission kickdown linkage from the carburetor is intact and properly adjusted. If it is not adjusted properly, the transmission fluid can become hot (hot enough to burn and become discolored). Transmission fluid runs through a cooler built into the radiator, if the fluid gets hot enough, it can cause the car to overheat. You should also check the radiator to make sure that it is clean and unobstructed.

Carburetor adjustment isn't too difficult. First, you must set the ignition timing to factory specs with the vacuum hose leading to the distributor disconnected and plugged. Then you set the curb idle (with the screw at the throttle linkage) to the proper speed. Then you will take a vacuum gauge and hook it to a full-time vacuum source. You will then adjust mixture screws on the front of the carburetor until you get the highest vacuum reading (the idle speed will change), then reset the curb idle back to the proper speed. Remove the vacuum gauge, and reconnect your vacuum hose to the distributor, and you should be done.

 

I have a very similiar problem with a 68 Chevy Chevelle 383 stroker engine. In addtion to everything the guy said above once the car has coasted into the gas station and I put it park and restart it it will want to stall everytime I try to go from park to drive. Gotta somehow keep RPM's up while shifting from park to drive. All the usual things have been done to the cer. sensors, timing, carb,fuel filter etc. Now they are telling me that my problem is with the HEI Distributor problem with timing and I need an ignition upgrade (new distributor, MSD High power box, and ignition coil). They also recommend a installing a stall converter. All of this will cost me the ONLY $2150! What I am afraid of is I sink this money into the car AND THAT STILL DOESN'T solve my problem because maybe I just a NEW engine! IDK. Very confused on what to do. Please HELP ME!!!!

 

it gets hot and cuts off,thats electronics in the distributor breaking down,either the pickup or condensor needs replacing,or if its got a electronic ignition box replace it next then the coil in that order,most likely its in the distributor,its also a good thing to keep these items on hand as extra in case you do have a break down while driving,

 

It could be a few other things. Do you have stock manifolds or headers. If you have the stock manifolds then the thermostatic exhaust valve could be stuck closed forcing hot air under the carburator causing the vapor lock. If you have headers disregard that. That valve is ment to heat the carburator and fuel up for cold driveablity. I also had a wierd one once on my own car with a 383 in it. When it was cold it would start and run good...If it got hot it would shut off and I couldnt restart it. I took the fuel line off and no fuel was pumping out of the fuel pump when hot. I replaced the fuel pump with a cheap 20 dollar fuel pump from southern auto and the car never had the problem again. Not sure why temperature affected the pump but it did. Another thing to look at is when it is hot and stalling can you look down the throat of the carb and see gas running out of your venturies? If you can then you are probably boiling the fuel in the carb and causing it to run rich and stall.

 

I had this similar problem on a 383 with the same solution, the fuel pump wouldn't pull/push when warm. Replaced the fuel pump and it ran great.

On a 383 Magnum that I had, the fuel pump push rod which rides on the cam and pushes the lever on the fuel pump, wore down to the point that it wouldn't push enough fuel at low rpms but, with some rpms it would run. I had never seen this happen before. I replaced the fuel pump push rod and all was well.

On another 383, I thought that it was the fuel pump push rod and it ended up being that the cam lobe for the fuel pump push rod had gone flat. An electric fuel pump was the quick fix for that.

 

yeah I have heard of the fuel pump push rod wearing down as well. more good insight.