VCCA Home Forums TECHNICAL - 1945 AND NEWER 1965-1970 1965 Impala 283 bogs down

I have a 1965 Impala 283, auto, my mother bought new. It was difficult to start after sitting unused some 10 years. I replaced the carb and fuel pump. It now starts and idles, but under any load, like going uphill, it bogs down and the engine dies. What are some fixes I can try...thanks in advance.

First place to look and consider replacing parts is the ignition system. Then engine needs a hot spark particularly when loaded. Most suspect are the points and condenser. I would first clean the points and make sure they have proper gap. Points tend to form an oxide layer when not used. Wife's emery board, striker on match box, nail file, fine sand paper, crisp dollar bill, etc. can be used. Make sure nothing remains after abrading. Moisture can affect the function of the condenser.

The condition of the fuel can also be an issue. Old gas maybe even when diluted with fresh does not burn as well as new.

Crap n gas tamk and gas line preventing full flow of gas.

Consider replacing gas tank , new tanks are not that expense. I have several friends that purchase cars that sat for long periods and had issues with bogging down until they replaced tank(which fixed issue). What happens debris on tank surfaces come loose with new gas a block flow.

Thank you for the really good suggestion.

Thanks Chipper...I'll try your suggestions.

Does the Impala have a two barrel Rochester carburetor? If so a common problem with them is hesitation on acceleration and surging at certain speeds. If bad enough the engine will die. They must be squeaky clean with good parts and adjusted to run well.

My guess would be the accelerator pump in the carb. Had a 283, around 1965 that would bog in a heart beat. One of the guys at the Chevy dealer where I worked part time bent the linkage that sat the pump "down" into the carb a little deeper and it never gave me any more problem......but I was running a 4 barrel Rochester. Just food for thought.

Many possibilities, some of them:

(1) partially clogged fuel filter
(2) partially clogged sending unit sock or pickup
(3) old fuel

The accelerator pump, if defective, may cause a bog or hesitation leaving a stop sign. Hesitate, then recover. Doubt that it is causing the issue posted.

My guess would be ALL of 1, 2, and 3 above.

My low compression John Deere won't burn gasoline that is 6 months old until the engine is completely hot. If you have not done so, drain the tank, flush, and pull in fresh fuel.

Jon.