Thread: Carb problem?
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Old 04-01-2008, 03:36 PM   #17 (permalink)
don71
feed the pig
 
Join Date: Jun 2007
Location: Central Missouri
Posts: 170
Quote:
Originally Posted by Pghstarsky View Post
I think I've narrowed it down to the carb though. The other day on a straightaway I floored it and it backfired through the carb as usual, but this time I didn't back off the throttle like I usually do. After the backfire the secondaries worked like a charm and that son of a B took off. It's just a backfire right when the secondaries kick on. So I think it's probably the secondary metering rods.

Any thoughts???

The secondarys....Thats a good guess, wish I had more experience with your carb but I don't. This sounds like a typical lean condition. When a quadrajet does this, the secondarys air valve is coming in too soon, or allowing too much air for a given amount of fuel, but that carb is NOT what were talking about here.

I wish I understood earlier that it only backfires when you mash the throttle. Then we could have gotten past the electrical non-issues more quickly. or maybe not......edit......

Ok so I'll back up a little.....like what was mentioned you need to make sure the HEI is fed by a full 12 volts. Thats the easy part.......you simply need a volt meter. Notice on the top of the cap where the wire connects...it says..or it should say..
BATT
GRND
TACH

At the batt terminal it should have 12 volts with the key in the on or run postion.

That could expain why the fuel is not being iginited properly.
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Last edited by don71 : 04-01-2008 at 03:57 PM. Reason: re...
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