My 65's 283 was running like a Singer sewing machine and all of the sudden, it started missing very badly. It's worse while trying to accelerate. It will backfire if I step on the pedal too much. Once it reaches a steady speed, it runs OK. It starts and idles just fine.
It's a Rochester 2 bbl and has the original point distributer.

So far I've: checked the timing-OK

Dwell is 30 on the points.

Cap & rotor is good. Plugs & wires are new.

Disassembled carb, reset float height. No dirt. Accerator pump shot is OK. That is the simplest carburator I've ever seen!

Fuel pump seems to work OK. (Cranking the engine with the line disconnected sends a good stream across the engine compartment)

I'm stumped. What next?


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MY 69 (http://www.chevelles.com/cgi-bin/xchange/xchange.cgi?search_and_display_db_button=on&db_id=22&exact_match=on&photo_size=full)

Fuel filter?

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My Web Page (http://www.landry-family.com) (updated 2-19-02)

"America will endure!"

Chad Landry
TC Member #643
ACES Member #04556
'68 El Camino

Try putting a timing light on the #7 cylinder and bring the light into the car with you. Take a test drive and make the car run badly. If the light is erratic, it is ignition, if the light is regular and steady, it is carburetion. Yeah, it sounds a little silly, but it does work OK.

Fuel filter is the stock brass 'plug' in the carb. It's clean.Good idea on the light. I like trying wackey stuff!

Sounds similar to what happened in my 283. Put Champion plugs in and developed a miss after a month or so. Turned out 7 out of 8 of the plugs had broken insulators. Worth a check if the fuel filter doesn't fix the problem.

Mike

Same very thing is happening to my 67 283. Had two people said they had it happen to them and it turned out to be a leak in the carb base or intake manifold. Going out to check into it now and will let you know.

After replacing the fuel system, sparkplugs, points, condensor, and coil, I found the problem. The distributer! Theinside part that moves for the advnce was locked up and wouldn't move. New distributer from Discount auto parts store - 37.95! Points & condensor included. I like old cars!

Glad to hear that you got it fixed! Thanks for sharing the solution with us. By the way, was it the vacuum advance or the centrifugal advance that messed up?

Mike

The centrifugal was locked up and so was the vacuum. Why it happened all of the sudden....Haven't a clue. When I tried to dis-assemble the original distributor, I broke and thought I was shot for getting it running. On a whim I called Discount auto and was surprised to see they had one. Too easy!