Quadrajet Problem Solving > Dialing in your rebuilt Quadrajet carburetor

Freshly rebuilt quadrajet flooding from top of carb

<< < (6/10) > >>

gregcarter:
Ok, I finally figured this one out, after basically remanufacturing the carb.

It was......... filthy, rusty, watery, dirty  gasoline.

I tried to start it one day and it wouldn't, noticed that no fuel was coming out the fuel line.

I emptied the tank, rinsed with phosphoric acid, rinsed with alcohol, and then acetone.

Then put a liquid liner in it and a new sending unit where the water laden air was entering nightly.

All this was expensive and stupid because a new tank was $90. The chemicals and liner cost more.

I flushed the lines and installed a new inline filter and a second one in the carb.

Fired right up and never stalled again.

So thank you Mr. Rugles for the carb lesson, I think I probably can fix one correctly now.

G. Carter

Cliff Ruggles:
Good news!.....Cliff

gregcarter:
Ok,Its not over yet.......
Thought I had it running good but it still kind of stank at idle as it always did for 15 years. The a/f meter said rich at idle and cruise.
A little history......
 This carb, an Edelbrock 1902, has 3 vacuum fittings on the baseplate.
The egr vacuum, the vapor canister, and the PCV lines.
This truck had a 6 cylinder motor in it stock.
When I converted it to a V8, I had a Rochester quad on it, and don't remember how I hooked up the PVC and vapor lines.
When I put the Edelbrock carb on it, I hooked both the PVC and vapor lines together with a T that was on the engine when I bought it. (per my mechanic partner)
The vapor line fitting was hooked up to the canister on a second fitting that opens a diaphragm that allows the vacuum from the manifold to suck out the trapped vapors in the canister.
It seems to me that the PVC line should go to PCV valve alone..
The vapor line should go to the cannister, and the diaphragm activator should just be teed into the same vapor line.


Can anyone direct me on this????

The richness need to be addressed.

I increased the idle tubes to .035 from .032 during the rebuilds.
Since its rich now, and probably always was, I should go back to .032s???
And since the idle mixture affects cruise, should I wait to change jets or rods?

I have:


main jets                                 .069

rods                                        36B


in there now.

The main jets have been in and out many times and don't look so good.

I didn't mention that the idle screws do little, it still runs when all the way in.

I just ran the motor with the idle screws in all the way, and had high O2 (.950-990) readings.

When I backed them out the motor slowed down.

What do you suggest?

Thanks ahead,

G. Carter

Cliff Ruggles:
Correct, the PCV line should only be going to the PCV valve.....Cliff

gregcarter:
Ok, I went ahead and replaced the .035 idle tubes with the .032's you sent and the idle appears controllable.

I took the truck to get smog checked and the co levels were 4 times higher (super rich)  than 2 years ago.

I had installed .042 lower mabs (there were no original lower mabs) and replaced the .052 upper mabs with .042s per your recommendation during the rebuild.

This is the only place I can think of that the richness was made.

In your recipes in the book, the smallest mabs are  .070, so I'm not sure why .042 were specified.

Should I yank the lower mabs back out, or drill upper and lower mab pairs out to get some air into the main system.

If you do recommend drilling them out, what size would be good?

Thanks ahead,

Greg Carter

Navigation

[0] Message Index

[#] Next page

[*] Previous page