Plea For Help...Truck Carb....Mechanic..

Smj · 04-04-2008, 06:55 AM

I'v got a 1984 GMC 1/2 ton pick-up with a 305 and a troublesom 4-BBL Quadrajet "quadratoilet" carb. I've gotten the impressoin that it takes a special guy to work on these things. Well, I'd like to know if anyone has ever replaced the Qudrajet with something else? Or knows a guy that is straight, and doesn't charge a load of bucks to "Not Fix" it. One of the issues is that it's got quite a bit of polution control stuff on it, and this other guy tells me "No parts are available anymore". So I'm supposed to take a perfectly good truck, with a low mileage motor and throw it away?

Am I the only person in this world that doesn't tow their boat with a reasonably new $30,000.00 truck? I hope not!

Smj

fishkisser · 04-04-2008, 07:26 AM

Sorry your having trouble with your carb ... I know you want to repair it but as I remember the 305 got poor fuel economy and was pretty gutless ...
Have you thought about swapping it out for a 350 ? I can pretty much guarantee you will have better fuel consumption and a lot more juice to go over the hills ... Other than that if it is a computer controlled Quadrajet most of them ran too rich anyway ...

This is what I would do ... Disconnect E.C.U and remove harness ,pull Quadrajunk and manifold , throw away ...

Purchase Holley street avenger 570 cfm 4 barrel carb ...
Purchase Edelbrock non E.G.R manifold ...
Install, adjust carb and enjoy ... Barney

Smj · 04-04-2008, 07:46 AM

Thanks Mr. Kisser....Well, I goofed when I had the re-built put in, should have opted for the 350. At the time I didn't realize, and the re-builder never told me, but a 350 would have been fine with DEQ...Who's your dummy!! Prob is I've still got to pass DEQ. I've been in contact with a recomend this morning, and I'm going to give the guy that "Charges but doesn't fix" another chance, as recomended by the recomeded...Sheesh. This other guy claims he's got all kind of tricks for the "Quadratoilet" and that it IS a good carb, and cheaper to set-up at this point than the whole new Edelbrock, Holly etc.

We'll see!

Smj

1pump · 04-04-2008, 10:04 AM

A lot of that early 80s GM stuff wasn't tuneable, at least not easily. One cute little trick GM used on their QuadraJokes was to seal off the mixture screws behind pressed-in plugs that were pretty hard to get out.

I have an F250 beater that had carb issues, and I also live in DEQ's jurisdiction. The truck came with a 4160 Holley 750 that was way too big for the 360 engine. The model year was also when they started using EGRs, but not all of the trucks had 'em, and mine showed evidence of an EGR being removed. I figured I was in for a nightmare of jumping thru hoops just to get tags. I even started making plans to keep a "smog friendly" engine on the side to install every two years, pass DEQ, then yank out again (it's easier then it sounds).
Luckily, cooler heads prevailed. I decided to give it a try with a smaller 600 Holley that I found on e-Bay for $50. I rebuilt it, jetted it down and installed it. I knew I could get it to pass the tailpipe test, but I was worried that DEQ would look under the hood and tell me to take a hike and not come back until I replaced all the useless crap that was missing.

Much to my amazement, they didn't look under the hood, and they said they generally don't anymore. My truck passed the sniffer test, and I recovered from shock in time to drive home with my new tags.

The moral of the story is that it might be easier to get thru DEQ than you think. If you have stuff like mixture control solenoids, vent solenoids, spark delay valves, vacuum amplifiers, ported vacuum switches, etc etc that are causing problems, you can probably chuck 'em and pass just fine.

cascadebull · 04-04-2008, 02:23 PM

Savas tuning KNOWS how to rebuild em, your average mechanic does not. If they cant help you theres a couple of guys online you can order from that have reputations for quality. Sure you can go aftermarket but you wont get the gas mileage you would from a Rochester properly built.

DirectDrive · 04-05-2008, 08:04 AM

I have a Jeep Cherokee (carburetor) with 413K on it. Last DEQ cycle I did my usual trickery and it didn't work. Got real close but no go.
I put on a new catalytic converter and it sailed through all the tests.

So if you rig is running OK and you're wanting to pass DEQ testing, consider a new cat con. My local shop swears by Magna Flow cats.

If you still need to have your carb rebuilt, SAVAS as mentioned is one option, but pricey.
There are some others around Portland but I haven't had any experience with them.
RH Carburetor Service
Merles Carburetor

Also, a good auto parts supply house would know who the top carb guys are.

luckyr · 04-05-2008, 08:50 AM

I have a quadrajet on the shelf here but I took it just because I might be able to use it on my old boat. I got it from my huntin fishin partner. You could PM him and see if it has any real issues. His ifish name is RGB. If it sounds okay to you I would be glad to give it to you. Do they go bad and become unusable after sitting a couple of years?? It was on a 350.

Smj · 04-05-2008, 09:32 AM

I've talked to the guy I've paid $140.00+ to and he wants me happy, so next week he gets it again. This guy is a GM guy, was a recomend from an aquaintance with the most cherry early '70s pick-up you ever saw, and had done a buch of work for him on his other '80s GM cars also. Majhor Murry was the other shop I called (due to a recomend from an old Chevy truck owner at the Swan Island boat ramp), and talked to the BOSS, Bruce. That guy sounded to me to be real good, I've done quit a bit of wrenching in my time so I can seperate the wheat from the chaff when it come to these folks. Don't treat me like in idiot, I my be dumb, but I'm not stupid!

1pump
""The moral of the story is that it might be easier to get thru DEQ than you think. If you have stuff like mixture control solenoids, vent solenoids, spark delay valves, vacuum amplifiers, ported vacuum switches, etc etc that are causing problems, you can probably chuck 'em and pass just fine.""

You trying to make my head spin completely around?? I don't believe this carb is computer controlled, electric choke and lots of vacume lines though.
I'm not opposed to spending the money, and from what I hear the Quadrajet is a fine carb, but needs someone who knows them intimately. I believe this guy is good, and old enough to have worked on them first hand in his early years. This guy has suggested removing a bunch of "crap" to make things simpler, and if that's what it takes so be it, he has the machine to see that the exhaust meets testing standards. So I'll pay what ever to have dependability.

Thanx for the carb offer luckyr, but I don't think anythings wrong with the carcas of my carb.

DirectDrive...a couple of years ago I had deul exhausts put on and I have two cats now! When she's running good the exhaust is as sweet as can be!

Thank for the replies guys!

Smj

fish_on · 04-05-2008, 12:06 PM

Nothing wrong with the Q-jet, just get a good rebuild and have them replace all the bushings. There is a great place in Olympia called Motors Unlimited that has a old guy who is known as the carb expert of Puget Sound.

There really isn't anything special to rebuilding them, but if your bushings need replaced it takes some special equipment.