Diagnose my carb problem

[MNcarbturbo]

Whenever I am running around at below 40MPH and smash the throttle (WOT) I notice my vaccum guage sometimes jumps. Goes up to 8PSI then jumps back to 25" of vauume then jumps back to zero. All in a fraction of a second After once or twice of that (about 50% of the time) the car starts to pull and boost. I cant tell what its doing for sure. Kindof hear a slight poping sound and the engine sounds like it stops or hesitates. Worse at low speeds than at highway speeds. Took 2 shaky vidoes to show.

 

[charlief1]

Sounds like the secondaries aren't opening right. I'm guessing but you might want to check the pull off at the front of the carb to see if it's working right.

 

[MNcarbturbo]

Ill try to do that. Aparently the previous owner rebuilt the carb so theres a good chance it got messed up.

 

[dr_frankenstein]

sounds like time for a holley.

LMAO

A.j/

 

[MNcarbturbo]

Its the plan in the future. Theres a 650 Holly vacuum secondary sitting on a truck that needs an engine rebuild. If the truck wasnt used it would be on.

 

[charlief1]

Here we go again. A Holley isn't the fix for everything Aj. I'll just have to prove it to you one of these days. (big sigh)

 

[dr_frankenstein]

Here we go again. A Holley isn't the fix for everything Aj. I'll just have to prove it to you one of these days. (big sigh)

it wouldnt be anyfun if I didnt rib ya once and awhile!

A.j.

 

[charlief1]

it wouldnt be anyfun if I didnt rib ya once and awhile!

A.j.

Sorry Aj, I was a little craby last night. I'm working on a blasted back hoe right now and it's a pain.

As far as using the Holley you need to see what's going on with the Q-jet and make sure it doesn't happen on the Holley.

 

[dr_frankenstein]

Sorry Aj, I was a little craby last night. I'm working on a blasted back hoe right now and it's a pain.

As far as using the Holley you need to see what's going on with the Q-jet and make sure it doesn't happen on the Holley.

LOL aww no worry Boss.

we all have rough days. Thats why I drink like a fish.

but its abosolutly true about making sure that its not something else before messing with the carb.

:biggrin:A.j.

 

[mikemcvaney]

LOL aww no worry Boss.

we all have rough days. Thats why I drink like a fish.

but its abosolutly true about making sure that its not something else before messing with the carb.

:biggrin:A.j.

I agree with A.J. its time for a real carb. Mike

 

[charlief1]

I agree with A.J. its time for a real carb. Mike

Just wait until I send one of my Q-jets to Aj, Mike. I think he'll have a different oppinion.:biggrin:

 

[jimski]

Is the waste gate opening up to early here?? or some vaccum leak. Just a thought.My car would boost to 9psi then start to hesitate and u could see boost gauge dropping before my eyes adjusted the waste gate and boost's hard now no hesitation.As for popping maybe quadrajet is starving in the secondaries

 

[WkillGS]

My Q-jet used to go lean just as the boost started to come up.
Resulted in a nasty lean backfire thru the carb. scary.
I played with the accelerator pump shot and secondary opening rate, maybe I richened it up too, don't recall... long time ago.
The Q-jet always worked well for me.

 

[MNcarbturbo]

Kinda fooled around with it today. Engine was cold but the choke was open so it shouldnt matter. When it idled and I gave 50% throttle I heard a pop and felt a small puf of air come out the air box. Pulled off the carb hat and did the same thing and a white plume of air came out the top of the carb. There was some fuel mixed it too. I am starting to think its almost more with my cam degreeing than my carb now. Whenever the engine gets fuel and air too fast it "burps". I hate to call it a backfire because it isnt that loud and there isnt any flames.

Not sure if im going to get the engine worked on this spring or not. Found a 85 salon and 82 parts car for $500. 85 has a nice interior so it looks like the powerplant will be taking a break unless I scrape some funds together.

 

[charlief1]

It almost sounds like your timing is off some. Is it advancing right?

 

[MNcarbturbo]

Yes. Pulls the timing back when it revs up. I know that the recomended is like 15 and I have it set to 18 initital.

 

[charlief1]

It's pulling timing out when you're not in gear?

 

['80RegalT-type]

Since were talkin carbs here. I was wondering if anyone knew casting numbers off the turbo carbs. I'm pretty sure the one on my car isn't. The only numbers I found on it were on the drivers side of the carb as follows:
17080243
2649 CNO

Since i'm pretty sure this isn't a turbo carb. Does anyone know where I can get a good reman or has anyone gone the route of a turbo specific holley?

 

[charlief1]

BEFORE BLACK - Carburetors

This should help you some. Try looking at the parent site so you know more about the cars.

 

['80RegalT-type]

Thanks for the link. That was indeed helpful. The reason I thought my carb wasn't a turbo carb was that when it makes boost it pushes out the main metering rods so when I come off full throttle she runs uber rich. I guess I just need to figure out which vacuum line goes to the metering rods.