I have a 390 ford in my 62 galaxie. When I first hit the gas at a stop light or coming out of a turn it spudders. I does it when it is warm and cold. I can't figure it out. I am not talking about putting my foot in it but when I "feather it" ( I does it and dies when I put my foot in it at a light). sometimes I hear a pop in the carb. I am not sure what it is or what the problem is. it has a petronix dissy and a "dialed in carb" (according to the guy I got it from).
sounds like the accelerator pump in the carb. the leather or rubber plunger on it must be cracked or out of shape.....joe
That is definitely where I would start also. Not getting enough of a hit off the Accelerator pump will cause the exact problem you are describing. If You give it little "taps" and that keeps it from stalling, that usually means the AP is not sending enough fuel. Then it will smooth out once you gain a little speed because the venturis start pulling fuel.
I'm not sure if you can buy an accelerator pump seperately or not, you may have to purchase a kit, then you can use just the pump and keep the rest for future needs. Are you sure that your carb couldn't use a total rebuild anyway? JayD
on my FE engine, i was having similar problems and it turned out to be that the manual choke cable sucked and wasnt adjusted right so the choke fly wouldnt open all the way, causing extra fuel to flood in, esp when the main flys opened up all the way. just two cents.
If the Carb/& Accellerator pump proves to be working all right, try this.... Has the vacuum advance been removed, during the Pertronix install? Remove dist cap,check if the Points monting plate moves freely. Using a mightyVac/hand pump-connect it via a tube to the Distributor's Vacuum advance servo/cannister, and check it for correct operation. This can cause a similar symptom, if your timing is not advancing properly......
What brand of carb is it? If it's a replacement holley then there are several accelerator pump cams that activate the pump, as well as the "big" 50cc accelerator pump that all can be used for tuning off-idle stumbles... The pump diaphrams can be purchased separately for most carbs, but the ones with the plunger (Q-jet, carter, edelbrock, etc.) I haven't seen separate accelerator pumps - probably becasuse you've got to open it up to change. To check if the pump is even working - warm up the engine (to open the choke and fill the bowl with gas), then shut off the engine, pull the aircleaner, while looking down the primaries open the throttle - you should see a nice strong shot of fuel come out - if it's weak or doesn't come out at all the pump is shot. If it's a holley then try changing to the next hole furthest from the diaphram up on the accelerator pump arm (more shot with less throttle movement) - also check the gap between the AP cam and arm - tighten it up if necessary.
It wasnt tuned it was tuned up...........the carb was replaced twice as a matter of fact. when I first got her it stumpled likt this. I tuned it up and replaced the carb with a TOMCO rebuild....drove it down south about 3hrs each way then she wouldnt start after sitting unless I shot some starting fluid in it. then it was fine. So when I got back I replaced it again (under warranty) and its been fine until now. There may be a chance the AP has rotted from being on the shelf so long??
Some FE's had a plate under the carb that was plumbed to the heater. It that still there?? If so bypass it that may be your problem. Dawg
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