'64 Stalls - Help please !

[helmutzerber]

adJust finished complete resto of my '64 327/365 hp. It was running great, I was enjoing it. etc... suddenly last week, it won't stay running. It starts great, but once the engine warms up, it won't idle - it stalls out. I can restart it, but it won't stay running unless I keep the idle high by pressing the pedal. I changed the power valve in the carb, changed the fuel filter, checked the fuel levels, etc.... Someone told be it's maybe a vacuum leak. There aren't too many vacuum hoses.... I checked these, all are tight, etc....

:confusedI have no idea what to do. It runs strong when I rev it, but the moment I let go of the pedal it stalls. Could it be the fuel pump ? I just put it in during the resto.


Any help/insight is greatly appreciated.

 

[jimbo64]

adJust finished complete resto of my '64 327/365 hp. It was running great, I was enjoing it. etc... suddenly last week, it won't stay running. It starts great, but once the engine warms up, it won't idle - it stalls out. I can restart it, but it won't stay running unless I keep the idle high by pressing the pedal. I changed the power valve in the carb, changed the fuel filter, checked the fuel levels, etc.... Someone told be it's maybe a vacuum leak. There aren't too many vacuum hoses.... I checked these, all are tight, etc....

:confusedI have no idea what to do. It runs strong when I rev it, but the moment I let go of the pedal it stalls. Could it be the fuel pump ? I just put it in during the resto.


Any help/insight is greatly appreciated.

hAVE YOU CHECKED THE CHOKE OPERATION, SOUNDS LIKE HANGING UP

 

[helmutzerber]

Thanks for the reply. How would I check this ? The flap opens fine as the engine warms, just as it should, but won't stay running. I am beginning to wonder if there coul dbe something with the distributor - my perktronics... as the idle drops as the engine gets warm, could something be happening with the spark/timing that is causing it to stall ?

 

[JohnZ]

Thanks for the reply. How would I check this ? The flap opens fine as the engine warms, just as it should, but won't stay running. I am beginning to wonder if there coul dbe something with the distributor - my perktronics... as the idle drops as the engine gets warm, could something be happening with the spark/timing that is causing it to stall ?

Is your base idle speed screw properly adjusted? It sounds like it idles fine when cold (on the fast idle cam), and as it warms up and the fast idle cam drops out, it reverts to the base idle speed screw (on the driver's side of the primary shaft), and stalls.

The base idle speed screw should be adjusted with the engine fully warmed-up, choke fully open (fast idle cam dropped out) at 850-900 rpm, and the idle mixture screws adjusted for highest steady vacuum.

What's your base timing setting (vacuum advance disconnected and plugged), and have you verified that the vacuum advance unit is functioning?

 

[helmutzerber]

??

I will check.... but it was running great, I parked it in the garage, and then this. Something went ? I noticed today when I started it with the doors open, that the interior lights flicker slightly while running. Could this mean anything ? Also, the battery drains while sitting for a day. That's something else that is new. I have to keep charging it. I replaced it, but same thing.

 

[helmutzerber]

Is your base idle speed screw properly adjusted? It sounds like it idles fine when cold (on the fast idle cam), and as it warms up and the fast idle cam drops out, it reverts to the base idle speed screw (on the driver's side of the primary shaft), and stalls.

The base idle speed screw should be adjusted with the engine fully warmed-up, choke fully open (fast idle cam dropped out) at 850-900 rpm, and the idle mixture screws adjusted for highest steady vacuum.

What's your base timing setting (vacuum advance disconnected and plugged), and have you verified that the vacuum advance unit is functioning?

I have a pertronics system on my original distributor. How do I check to make sure the vacuum advance is functioning properly ?

 

[JohnZ]

I have a pertronics system on my original distributor. How do I check to make sure the vacuum advance is functioning properly ?

Connect your timing light with the engine warm and running with the vacuum advance hose disconnected and plugged, like when you set your base timing, and observe your timing setting. Then re-connect the vacuum advance hose; the idle rpm should increase, and the timing should increase by 15*. This assumes that you have the correct/original Holley 2818 carburetor with the vacuum advance line on the full manifold vacuum source port.

 

[helmutzerber]

Connect your timing light with the engine warm and running with the vacuum advance hose disconnected and plugged, like when you set your base timing, and observe your timing setting. Then re-connect the vacuum advance hose; the idle rpm should increase, and the timing should increase by 15*. This assumes that you have the correct/original Holley 2818 carburetor with the vacuum advance line on the full manifold vacuum source port.

Yes, it's the original carb, restored. The problem is keeping it running. I can't. Once it warms up, the idle drops to around 900 -1000, flutters rough and then stalls. The only was to keep it running is with my foot on the gas.

 

[Rex S]

Another thing to look for is vacuum leaks. With a big enough vac leak, the engine will act just like that. Check for open (unused) ports in the intake manifold, carb not sitting square and flat on manifold, badly leaking power brake booster (even if just replaced), stuck open PCV valve, etc.

 

[helmutzerber]

Another thing to look for is vacuum leaks. With a big enough vac leak, the engine will act just like that. Check for open (unused) ports in the intake manifold, carb not sitting square and flat on manifold, badly leaking power brake booster (even if just replaced), stuck open PCV valve, etc.

Thanks. I disconnected the vacuum lines, plugged them, started it, and it still died once it warmed up. I used carb cleaner, sprayed all around, no change. I am at a loss. I'm nto sure what to do. Again, it was running fine, now this.

 

[helmutzerber]

Thanks. I disconnected the vacuum lines, plugged them, started it, and it still died once it warmed up. I used carb cleaner, sprayed all around, no change. I am at a loss. I'm nto sure what to do. Again, it was running fine, now this.

One more thing..... I can keep it running if i continue to spray carb cleaner or starting fluid into the carb. This leads me to believe it is being starved for fuel. I replaced the fuel filter, checked the fuel pump, checked the sight screws in the bowls.... all OK.

 

[Rex S]

Well if you have fuel pressure, the bowls are full and it will run with an outside fuel source (the carb cleaner) there is nothing else it can be but the carb internaly. Maybe trash, gunk, dead bug (?) stuck in the jets? No one "tightened" the "loose" idle mix screws by accident did they?

 

[Bronze85]

I'm thinking blockage within the idle circuit of the carb or an air bleed issue. Most likely the carb will have to come apart for cleaning and inspection.

 

[BLACK MOON]

Sounds crazy but rev engine while someone closes the butterfly until it dies. Years ago I used this to clear blocked circuits. Can't hurt to try.

 

[helmutzerber]

Well if you have fuel pressure, the bowls are full and it will run with an outside fuel source (the carb cleaner) there is nothing else it can be but the carb internaly. Maybe trash, gunk, dead bug (?) stuck in the jets? No one "tightened" the "loose" idle mix screws by accident did they?

Thank you so much for all of the information. I pulled the carb, went through it..... turned out it was a loose base plate. Put it back, it runs without stalling. Only thing is there is a slight hesitation when I press the gas now when getting off of idle. Any suggestions ? I adjusted the idle mix screws, fast idle, normal idle, etc.....

 

[BLACK MOON]

When you say went thru it what do you mean? Did you rebuild it or just disassemble and reassemble. If you put back old gaskets and o rings it could be anything. Spend the time and money to rebuild it properly. Now that you disturbed old gaskets (if that's what you did) it could act up on you anytime. Just my 2 cents. Keep us posted.

 

[helmutzerber]

When you say went thru it what do you mean? Did you rebuild it or just disassemble and reassemble. If you put back old gaskets and o rings it could be anything. Spend the time and money to rebuild it properly. Now that you disturbed old gaskets (if that's what you did) it could act up on you anytime. Just my 2 cents. Keep us posted.

Used a rebuild kit, so all gaskets, etc... was replaced. Soaked the carb, everything was cleaned out (although it was very clean to begin with). Not sure how the base plate got loose. It idles great now.... was burning my eyes so I leaned it out some... I have the idle mix screws out only one turn. The odd thing was the front metering block didn't have the tiny brass inserts... not sure if the metering block was used differently in it's past life... Not sure if I need to fix this, or what it does to the carb/car running. When I punch it (in neutral) it hesitates for a brief second and then revs up... I probably need to adjust something. I have very little carb experience/expertise.

I appreciate all of the help... If anyone can give me any suggestions on what to look for for the hesitation, it would be appreciated. Timing ?

 

[BLACK MOON]

Glad you rebuilt it. Good move.

You know I pulled the original carb off my 63 and replaced it with an Edelbrock which was been replaced with a Webber which was replaced with a Holley. My point being I don't remember the early carbs at all. Was it a Rochester or a Holley? If the carb has squirters I would start there. On the Holleys if it surges or lags on acceleration that is where I and most people start. Maybe John Z whill respond. He's the expert here. Most others including me are novices.

 

[JohnZ]

First thing I'd do is to adjust the accelerator pump correctly - that's a Holley 2818, and the procedure is the same for all Holleys:

1. Hold the throttle lever wide open (stout rubber band or third hand)

2.Depress the little lever on the accelerator pump all the way.

3. Adjust the spring-tensioned bolt/nut on the end of the linkage that operates the pump lever so you have exactly .015" clearance between the end of the bolt and the pump lever.

That will give you an instantaneous pump shot from the squirter with the slightest movement of the throttle lever.

 

[BLACK MOON]

I told you John Z in THE MAN!