I have a '78 T/A and I want to put the standard Quadrajet back on it but
I can't get it to stop flooding. I put a pressure gauge on the pump
outlet and at cranking it gives peak pressures of slightly over 10psi,
it is a new standard pump. I have connected an airline to the fuel inlet
of the carb (on the bench) and the needle valve will not seal at 10psi,
it will only work up to about 7. I have tried combinations of 2 seats
and 2 valves, all new, and none of them will seal.
There is no mention of a pressure regulator in the books and I have
never seen a caburetted car with one.
Please can someone tell me what I am doing wrong.
Hi david, Just a few thoughts (not teaching you to suck eggs etc ).
Does it seal at 7 when holding it upside down but not at ten ? (that would
appear to be the seat).
Also, is the float at the correct height .I've seen carbs where the hinged
plate is slightly bent and the float hits the underside of the carb
stopping it from sealing firmly.
If the level is too high, this can also allow them to flood(even though
the seat might be OK )
How are your return lines going to the tank? If they are
clogged/bypassed/screwed up, you could be getting a flooding condition.
What brand of fuel pump did you use? A Delco 41382 (depending on certain
conditions) is the stock GM pump that engine uses.
Joe--ASE Certified Parts Specialist & 10th Ann.Club Tech Director
'80 Carousel Red Turbo T/A, 27k orig.
'79 "Y89" 400/4 speed 10th Ann. T/A, 57k orig
'84 Olds 88 Royale Bgm 2 dr, 307 "Rocket" (lol), 143k and still going....
I would try to get either a New Old Stock Delco pump or a replacement Delco
from a dealer. A lot of the auto parts stores sell generic
When the original pump popped on my 84 T/A it had a restrictor in the return
line port. The auto parts store replacement had no restrictor and caused a
thumping sound from the pump. Went to the Pontiac dealer and got a Delco
pump, which had the restrictor, and solved the problem. Learned my lesson
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