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-   -   Help. 1965 running bad. (

OneXBigTom 07-23-2014 08:18 PM

Help. 1965 running bad.
I picked up at 65 with the original 289 engine. The car would not stay running. I rebuilt the carb replaced the water pump, fuel pump, wires, cap, rotor, plugs, coil, and points. New fuel tank and fuel line as well. Has the stock 4100 carb on it.

Son and I started her up and she ran great for 5 min then that was it. Runs ruff and cannot get it to stay running. While she was running she was purring and sounded great. She was burning a tad bit rich but was running great. I am running out or ideas of what to do next. What can cause it to run like crap after she warmed up? This is old school stuff and I am stumped.


Gun Jam 07-23-2014 08:51 PM

probably a blockage in the carb or a vac leak.

Check for a vac leak by sparying carb cleaning around the base of the carb and intake. On the intake spary where it meets the heads and all over around the back

Block off ALL vac lines before doing this a leaking brake booster or similar can cause an issue as well


OneXBigTom 07-24-2014 09:00 AM

Thank you for the reply. Still not finding any vacuum leaks. Fuel going in. Car is all stock 65. Matching numbers and every thing. Point gap set at .021 plug gap set at .032 (will increase to .035) Will keep digging. Need to walk away from it for a few.

bop11 07-24-2014 09:11 AM

Did you check valve adjustment? It may be good when cold but too tight when hot with loss of compression.
Did someone replace the coil resistance wire with a standard wire. Coil may be over heating and shorting out even if new it needs a resistance wire.
Electric Choke? may have bad element causing choke to stay closed. Non electric may have plugged riser tube causing choke to stay closed.

Gun Jam 07-24-2014 10:02 AM

If there is a carb blockage fuel will go into it just fine...its getting out that becomes the issue...if nothing else jumps out at you you'll likely need to disassemble the carb again.


barnett468 07-24-2014 05:19 PM


points are wrong should be .016 to .018.

plug gap is fine leave it.

put a timing lite on each wire to make sure all pugs fire.

look at color of gas. if it is yellow it is bad. if it is new gas, old dried stuff in the tank contaminated it. this can kill your engine in 5 minutes.

sounds like your idle circuit might be plugged. make sure you have a clear plastic filter just before the fuel pump. in your case having one after may be better for now.

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