3461S (Again)-327/340

[Les Jacobs]

OK, a month ago I pointed out a descrepancy in the Corvette shop manual with regard to the float level. Turns out my float level was set too low by about 1/8 inch (not enough gas in the bowls). After setting the float level properly, the off idle problem I experienced was cured- and after a minor tuneup the car runs like new! So whats the problem? It is now hard starting hot. Choke, starting motor,timing, etc all ok. Before the float adjustment the one thing it did very well was hot start. Now it acts like its flooded. (need to hold the gas pedal down 1/2-3/4 way and crank for 3-5 seconds)Ive checked the venturi after hot shut down and see no evidence of gas dripping into the carb. Suggestions?

[Clem Z.]

Re: 3461S (Again)-327/340

drop the float a 1/16" and see what happens. my standard answer on all aluminum intakes is to block the exhaust heat riser cross oven with stanless steel shim stock to get the excess heat out of the manifold because it is boiling the gasoline when you shut off the engine. on a 63 since you have a exhaust manifold heated choke the choke will still work.

[Les Jacobs]

Re: 3461S (Again)-327/340

Hey Clem I've checked the archives and thought you were going to say that, but just thought Id check. What I don't understand is .. how is the "high" float level causing the problem to begin with? Is the vaporized gas being vented into the throat after engine cutoff? ((Just thought of a way to possibly check that..take of the air cleaner, and hot start it)) Thanks Les

[Clem Z.]

Re: 3461S (Again)-327/340

i would guess as the fuel heat up it expands enought to be forced out the booster nozzles.when you had a low float level the fuel level was below the output of the booster nozzles and now it is at the correct level and when the fuel explands it is pushed out the nozzles. JMHO

[Les Jacobs]

Tnx. I'll try it. *NM*

[Verne Frantz]

Re: 3461S (Again)-327/340

Les,
If you block off the exhaust cross-over through the intake, I'd suggest you also wire the exhaust heat riser wide open, or the exhaust from that bank will have no where to go until the engine is at full operating temp. And it's a good bet the plugs on that bank will foul out pretty quickly.

Verne.