L76 Backfiring through the carb?

[Gary Wilkerson]

[Joe R.]

Re: L76 Backfiring through the carb?

Gary,

Check to see if you have crossed a couple of plug wires. I've been working on these things for xx years (I won't say it outloud) and just the other day I crossed #3 and #5. Exact same symptoms you have.

If it's not the plug wires, check the timing again.

Regards,

JR

[Gary Wilkerson]

Re: L76 Backfiring through the carb?

JR,

Thanks, I have made that mistake as well! I don't think that the problem however, it does idle seem to idle well and has good HP during driving.

Gary

[Doug Flaten]

Re: L76 Backfiring through the carb?

Vacuum leak? Vacuum leaks can cause a backfire.

[Joe C.]

Re: L76 Backfiring through the carb?

Gary:

What was done to the dist, and was anything else changed? Make sure that your advance weights are free to pivot, and very lightly lubed. Check your advance "curve" against the specs. If you need them, myself or others can provide them. If your engine has backfired, there is a chance that you have ruptured the power valve in your 2818. You'll know it because she'll load up and stall at idle.

Even if the engine is running right, the idle vac is so low (approx. 9-10 in-hg.) that it is not very hard to get the engine to backfire, especially if you have a tall gear. I'll bet that if you slip the clutch a little bit more, that she'll be fine.

Joe

[Gary Wilkerson]

Re: L76 Backfiring through the carb?

Joe thanks, I was worried about the power valve as well. The idle air screws still have an affect when changed, but I don't know if thats a true indication.
I did change the dist shaft and the busshings. The weights did move freely. I'm going to check timing again this weekend as well as the valve lash.

Cheers,