what's wrong with my carb? (i think)

['80RegalT-type]

My car hesitates and sometimes dies when i give it gas, once it gets past the hesitation if it doesn't die it runs fine. I can look down the venturis and see fuel dripping in. Got any ideas?

 

[Peter]

Try checking the float level, and the float needle seat for wear. Either could cause fuel seepage into the carb.

 

['80RegalT-type]

I checked the float level and the needle seat. Still leaking gas in. I can turn my idle screws in all the way and it doesn't effect the car at all.

 

[Peter]

You have to stop the fuel leak before you can do anything with the idle. It is my experience that the engine will not idle with the mixture screws turned right in. Full lean.

Is the float punctured? Does it rattle if you shake it? If the float is too heavy it may cause leakage.

If you can see the fuel leak inside the carb, can you determine where it is coming from? Gasket, cracked housing, porosity, which jet or orifice etc..

 

['80RegalT-type]

The float is in perfect condition. I ran it today and I believe excess fuel is comming in through the main discharge nozel in the boost venturi. It's doing it on both sides of the carb. Also i have to keep my foot on the gas to let it warm up. I checked voltage at the choke and it was dead. So i got power to it but still no effect.

 

[Peter]

I think that your fuel level has to be too high. I would suggest forgeting the measurements and set the float 0.060 - 0.125 lower than it is now, and give it a try.

Any other suggestion out there??

 

['80RegalT-type]

Well I tried lowering the float setting......no change. I've tried rebuilding this carb and i had a "quadrajet specialist" rebuild it after mine didn't work. I wonder if there's a vacuum leak or something drawing excess fuel in? am i crazy?

 

[Peter]

Well I tried lowering the float setting......no change. I've tried rebuilding this carb and i had a "quadrajet specialist" rebuild it after mine didn't work.

I am assuming this is a non-electronic controlled carb? There is an air bleed that allows air to bypass the venturis on some Rochesters. It is a fixed calibration, and its purpose is to allow the throttle plates to more fully close and still retain an idle. This also aids in preventing nozzle drip. Check to see if it is blocked?

There are also idle air bleeds which help prevent any siphon action occuring. These exit just above the idle tubes and should also be checked for blockage.

If this fails, try lowering the float more.

CRAZY??? These cars do have those effects!!

 

['80RegalT-type]

It's a non electronic controlled carb. I checked everything you said and still nothing. I pulled the carb off and went through it again. checked for any clogs, cracks or possible vacume leaks and put it back on. Still the same problem. the idle surges. it will run normal and almost die then back to normal. weird i must say. what a pick for a first motor build.

 

[Ttype83]

I would try a known good carb, take one may be warped or......

 

['80RegalT-type]

Ok, anyone got one i can borrow? lol

 

[Peter]

the idle surges. it will run normal and almost die then back to normal.

A surging idle is usualy a sign of air leaks. Not necessarily in the carb but anywhere in the induction system.

If the carb is still suffering nozzel drip ,I have run out of ideas!!

There is a book by Doug Roe on Rochester carbs out there. Maybe it's time for that??

 

['80RegalT-type]

Alright, i'll check around for air leaks. I do have that book by doug roe, guess i outta bust it out. haha. . I still gotta put in that alternate to the 3 port vacume switch. That wiring diagram is kinda confusing. thanks for your help pete.

 

[Freddie's Buick]

Dude....

I think its the float valve..... When the rubber wears it no longer seats and gas keeps coming into the float bowl. Under serious circumstances it would flood your engine. It is'nt a rare thing you know.

It happens....just get a rebuild kit. Or better yet, if you don't know how to do a rebuild....buy a rebuilt carb. I find most mechanics don't know jack about these carbs and I would'nt trust 'em.

They usaully screw it up more than what it was, then they turn around and charge you an arm and a leg and say that the cause of it was something else. It cost cheaper getting a rebuild even if the price is between 250-$300.

Good Luck!

 

['80RegalT-type]

Well, I'll check the needle seat again. It's a new one so it's not coroded but it still may not be seating all the way. The one in my edelbrock on my GS went out in the middle of traffic. It happened to be that one of the needles decided it just didn't want to seat.

 

['80RegalT-type]

Well I can't seem to get this carb to run right. I put a quadrajet from my friends cutlass to see if it ran better and WOW. She ran like a dream. So I decided to cough up the cash and get a rebuilt one from my local parts store. Hopefully when i put that one on it will still run good. I hate messing with my car when it's running right. i guess that goes with the old saying. I'll let ya guys know how it turns out. The carb will be in on the 6th of august.

 

[pat83t]

I had hesitation like that also turned out I had an open vacuum port on the back of the carb. capped it off and it quit.