Thread: carb is a gas

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hi guys,
well to start I've got a 350 chev tbi engine and I have refitted a gm alum duel port intake, retapped center holes for angle of bolts and all is sealed and tight. now the problem, have q-jet 4 bbl, went thru it and checked all 3 times, all ok. the problem is that I don't have any control over a\f adjustment or very little,won't idle,idle screw not in to far,timing ok, fuel press ok, all tune parts new, Think the idle circut is lean?, no vac leaks in intake or carb or gaskets,drilled out the restrictor orfice's and recleaned all and air checked. I have read all that I can read here and at other places including Lares site to no avail. any idea's on what to try or do next? and I already swaped to another (same number) carb and the same problem with it also.any help will make me very happy and the engine too. thanks in advance dave

What is the reading on your vac guage?

Here's an article I wrote that may help....
http://www.crankshaftcoalition.com/w...al_vacuum_leak

hey guys,
thanks for the fast reply, I'll have to get back to you bruce about the vac reading, it probably won't be what we think it should be-1- 4500 feet in elevation. 2- timming is a little high over stock. will check soon, thanks. techinspector- I read the page that you told me to check out and that is some pretty cool stuff, am going to take the manifold off and go thru the steps i read and see what happens and get back to you and everybody with the results. one more thing I forgot to state before, I noticed that right on top of the manifold on every bolt there is a puddle of oil in each valley area and the oil is down about a qt or so. sure is pointing to the intake being the problem don't it? thanks for all the help We sure do appreciate it. dave

If you are running the factory in tank fuel pump, you ARE running a fuel pressure regulator, correct? If not, then the pump has too much pressure and will cause it to flood, or run really bad. The factory pump can push pressures into the teens, and a qjet is suited for 7-9 psi usually.

Originally Posted by Weasel Diesel

If you are running the factory in tank fuel pump, you ARE running a fuel pressure regulator, correct? If not, then the pump has too much pressure and will cause it to flood, or run really bad. The factory pump can push pressures into the teens, and a qjet is suited for 7-9 psi usually.

My experience is that a Quadrajet will blow raw fuel into the intake starting at 6 psi.

Originally Posted by techinspector1

My experience is that a Quadrajet will blow raw fuel into the intake starting at 6 psi.

Yea, I knew it was around that area... And a EFI pump will push it on thru without a regulator.

hey guys,
fuel pump is mech and the pressure is around 5 psi,I think that it's going to be the intake in the end as said above. had to have surgery thurs, that wee can solve so I'll try to get back to it and you soon, I hope. thanks again dave