bjones9858

I have a 76 L48 with automatic. Got some excellent advice on timing a few weeks ago and after timing it, rebuilding the carb (edelbrock 1406) replacing the Dist. cap and rotor (Mallory Comp 9000) and realizing the linkage was not allowing WOT (fixed with spacers). It was running great - lots of power and acceleration -for a few weeks. Now a prior problem has returned. When I go to WOT from a standing start, it takes off great - some wheelspin - then within 50 feet it sputters and dies like it's run out of gas. IF I accelerate from a rolling 10 mph start it misses but picks up and goes. It's changed drasticly from just yesterday. if I punch it from 40 or 50 no miss but it's not as strong as it was. Timing hasn't changed. Pulled the Dist cap and noticed some black on the contacts. The old one was black and pitted as was the rotor. It's only about 3 weeks old, not more than a couple of hundred miles. All I did today was fill up with 93 octane. I usually run 89. and I replaced the rigged throttle mount with an after market one. It pulls the linkage to wide open OK though. The black on the Dist cap contacts concerns me but I'm stumped.
Thanks in advance.

Corellian Corvette

Is it possible that you're burning up points by running too much power to the distributor? Originally, it sounded like you may have some fuel pump problems, but the black and pitted rotor sounds like your points are burning. I believe there is a limited amount of current that is supposed to be drawn. If your points are bad you may not be getting good spark and that's causing the stumble.

What do your spark plugs look like?

bjones9858

Thanks Corellian, it's a breakerless distributor, no points. The new rotor is good - no black or pitting. It's the cap contacts that are blackened after only a few weeks. The plugs are partially blackened. There's a black section on about a quarter of the insulator kind of like a pie slice. The rest is white. And they're dry. I thought about too much power to the distributor. There's a resistor in the circuit but maybe it's not big enough. Hate to buy another new cap to test it (about 40 bucks). But may have to. I thought I might have over tightened the carb base when I put the throttle cable holder on. It's fastened under a bolt. But I don't seem to have any leaks. The dist. seems to be the most likely candidate.

Blkblt

lars.grimsrud@lmco.com

:yesnod: :cheers:

bjones9858

An update: Sometimes, not often, it is the easy stuff. Replaced the fuel filter and fixed the problem. Gas tank was almost empty when I filled up. Maybe I've got a lot of crud in the tank and it was sucked up. Thanks for the posts.

Alwyn678

Wow that was Lucky....Good for u :cheers: