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Old 08-25-2010, 02:33 PM   #1
bluec10
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Truck Stalls When I Step on the Gas

Arrgh.

I've got a '69 GMC with an 250/3 speed manual. It starts well and idles well. BUT, when I step on the gas to let out the clutch, it stalls. I have to nurse the accelerator to higher RPMS by slowly applying pressure to the pedal. After its rolling it runs pretty well and runs reasonably well on the highway.

What am I missing?
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Old 08-25-2010, 03:03 PM   #2
68gmsee
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Re: Truck Stalls When I Step on the Gas

Things to check:

First remove the breather and check to see if the accelerator pump/plunger squirts gas into the carb. If it does then check for vacuum leaks. Mine had a gasket leak on the bottom.

Take the cap off the dist. and disconnect the tube to the vacuum advance. Suck on the end of the hose to see if the vacuum advance moves freely.

Check your points if you have them for proper gap and the timing.

Also, you may want to get a kit for the carb. They're easy to take apart and give it a good cleaning. Readjust the idle air screw for maximum vacuum at idle.
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Old 08-25-2010, 06:52 PM   #3
LockDoc
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Re: Truck Stalls When I Step on the Gas

-
My money is on the accelerator pump not working...

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Old 08-25-2010, 07:13 PM   #4
Jacfourteen
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Re: Truck Stalls When I Step on the Gas

x3 on the accel pump
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Old 08-25-2010, 08:57 PM   #5
cparman
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Re: Truck Stalls When I Step on the Gas

Before you condemn the carb, make sure that you have checked to see that the point gap is correct?
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Old 08-26-2010, 10:07 PM   #6
kevmic28
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Re: Truck Stalls When I Step on the Gas

plug wires too. check em.
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