Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem
Dieseling
Chevynation:
Not sure what the current IAB size is. Carb was done two years ago if I remember correctly. 12” vacuum at idle. If I increase initial then yes it won’t run on but it won’t run on all the time. It doesn’t run on if I decrease the idle either but it’ll just be idling too low. If this was a double pumper I could simply open the secondary curb idle screw to add some air while keeping the correct amount of transfer slot exposure on the primaries.
Kenth:
What carb-#?
Chevynation:
7045213 it originally had a 7040203 body but it was replaced.
quadrajam:
I had the same problem with my previous 350. Tried every trick in the book and
then some. Even tried different carbs and distributor. Ended up using an anti deiseling
solenoid which worked. Problem with mine was horrible quench distance combined with
factory dished pistons. New motor has .036 quench and flat tops. no more deiseling,
even with exhaust heat under the intake and a 195 degree stat.
IAB mods probably not going to help as you will still be letting the same amount of
air into the engine for the same 800 rpm just from a different path.
The idle solenoid may be the best solution for now especially since it is running fine otherwise.
QJ
Chevynation:
Doesn’t run on with a different carb. My quench is tight. No carbon buildup on pistons. Why would you have to change the distributor? If I increase the idle bypass air by .010 then how would the engine be getting the same amount of air? I should be able to increase the idle bypass air to the point that the engine has a fast idle that can’t be lowered other than reducing the idle bypass air hole size.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version