A noob's adventures in old technology

[Jay2TheRescue]

The problem with taking a carb apart on a 1980 GM vehicle is that the thing is sealed. The carb was calibrated at the factory, then they blocked off the adjustments. he probably has the same carb that my 1980 Bonneville wagon did. A non computer controlled Quadrajet. With the emissions controls they were required to meet, GM decided it was best if the carbs were not able to be adjusted without completely breaking them down and rebuilding them. I would not recommend taking that carb apart unless you knew exactly what you were doing.

[theholycow]

Originally Posted by Jay2TheRescue

Which tranny do you have? I'm thinking you probably have a TH-350

Yup. TH350.

Originally Posted by JanGeo

If it is dieing right away when you hit the throttle

Nope. I should post a video. I lay on the throttle and it runs fine all the way through first gear. Maybe about 3000rpm in 2nd gear is where it starts gagging.

The stuck plug that was hard to turn could be carboned up threads or the outside of the socket binding in the spark plug hole.

I forgot to report back on that. I sprayed it with PB Blaster before I gave up that day. When I worked on it again a few days later it felt slightly better and I went ahead with it. It came out and a new one went in reasonably smoothly.

Originally Posted by Jay2TheRescue

he probably has the same carb that my 1980 Bonneville wagon did. A non computer controlled Quadrajet.

Yup. I think it's a M4ME.

[Jay2TheRescue]

Do you have a 1980 Buick service manual? If so, read up under the carb adjustment/repair procedures. It can be a real PITA. Some of them can only be adjusted properly while using a propane enrichment procedure. I saw that in an early 80's GM service manual and I just about **** a brick. There's no way someone could do that themselves, pretty much you have to have a dealer do it. The only guy I let touch the carb on my Buick is someone who used to be the carb guy in a GM dealer in the early 80's, and had the factory training to work on them.

-Jay

[theholycow]

I do not have a factory service manual...just a Haynes and a Chilton's.

I wonder what my options would be for getting it rebuilt, replacing it with a rebuilt one, or replacing it with a different carburetor. Simplicity (since I have no experience replacing a carburetor), reliability, and price would be my priorities...I'm not too worried about fuel economy or power from this car, at least for now.

[R.I.D.E.]

One step at a time grasshopper .

Verify the WAI is working properly before you do anything else, even the fuel filter.

[theholycow]

Yeah, I'm just queuing up ideas. I suspect this carb will need professional attention even after everything else is fixed. I'd love to be wrong.

Well whaddya know, I went to the Quadrajet forum on v8buick.com and right at the top was this thread:
http://www.v8buick.com/showthread.php?t=193090

[JanGeo]

From what my friends mother's Honda did - an old one with a carb - was it ran a little too lean with the ethanol and the jetting was the real problem. The accelerator pump is not working when your foot is holding the gas steady but that other metering piston mentioned in the last post of that link you have on the V8Buick sounds like an issue as well as the heat buildup as you get into second gear. Now if it was anything like my BMW motorcycle I could drive it for a mile on the gas in the bowels with the fuel petcocks turned off so depending upon how big the bowl is it could be that. Next thing would be to accelerate more slowly and see if it happens at the same rpm in 2nd or further out in 2nd or third. I think at this point the sealed carburator is a moot issue as far as emissions go. I seem to recall plastic caps on the jet adjusting screws that you could snap right off. Hey how about some Acetone and some Tolene to richen it up and clean it out. Remember these were the days of REAL gasoline and Gumout carb cleaner.

Oh if it sputters out at the same RPM then look into the coil and ignition system. but it could also be the mechanical fuel pump not moving enough to pump the fuel.

[R.I.D.E.]

Usually if the carb is bad, you can use a timing light to diagnose it. Hook up the light and point it down the carb, while you rev the engine. The strobe effect of the timing light will allow you to see if the fuel is properly atomizing or coming out in drops, instead of being properly atomized.

Avoid doing several repairs or adjustments at the same time. That way you are not left guessing which thing is compounding the symptoms you are trying to fix.

regards
Gary

[Jay2TheRescue]

Originally Posted by JanGeo

I seem to recall plastic caps on the jet adjusting screws that you could snap right off. Hey how about some Acetone and some Tolene to richen it up and clean it out. Remember these were the days of REAL gasoline and Gumout carb cleaner.

Maybe at some point there were plastic caps used, but in 1980 I believe that GM was using metal caps that needed to be very carefully drilled out if you wanted to mess with the adjustments.

[Jay2TheRescue]

I just noticed something really interesting... to www.google.com and type 1980 buick carburetor service procedures as your search query. Look at the last result on page one.

Enjoy!

Jay