1953 Chevy Truck Acceleration Issue

[ollinger123]

Hello everyone, I have a 1953, 3100, 216 Chevy Truck.  The engine idles ok, but when I accelerate, the engine bogs down - sounding like it's sucking air.    Here's what I've done so far:  Plugged the vacuum hose leading to the wipers, Replaced the fuel pump, Changed out the old gas, Dipped and cleaned the carburetor, Checked the gap on the points.

 

Please let me know what I'm missing...

Thanks,

Jon

[Guest]

Dirty/obstructed air cleaner or defective vacuum advance?

[Rusty_OToole]

Check the manifold bolts for tightness. Have run into this on 6 cylinder engines before, the bolts work loose causing vacuum leaks. Usually tightening is all they need, sometimes you need new gaskets. If this is the problem the bolts will be obviously too loose when you put a wrench on them. if they are tight do not over tighten.

[keiser31]

My old '57 Chevy truck with a 235 did that. I had to blow out the fuel line in reverse to unclog it.

[Bhigdog]

Put a vacuum gauge on it.....bob

[auburnseeker]

You might want to actually rebuild the carb with a new accelerator pump.  They get old and loose their elasticity so they don't seal so well and give you similar symptoms as you aren't getting that shot of gas.  OF course could also be the other things mentioned above. 

Check to make sure your exhaust isn't plugged as well with a mouse nest or in some rare cases,  the muffler can fall apart inside and plug the outlet. 

Edited September 6, 2018 by auburnseeker (see edit history)