quadrajet questions

[chevybowtie]

So the last few days I've been working on my q-jet. It's my first time endeavouring to rebuild the q-jet myself. Previously I've been taking it to a local speed shop to get rebuilt, but last time I got one worked one they overtighted then idle mixture screws and wrecked the baseplate, and never told me about it. So I have some questions, cause I want to be doin this myself from now on.

Is it safe to have the carb sent to a machine shop and planed to restore flatness? I'm referring to having the top and bottom of the main body, and the top and bottom of the base plate planed. Will that cause problems in any way?

Where is a good place to buy a rebuild kit from? I'm open to recommendations. I'm assuming I'll have to do mail order. There aren't really any speed shops in my local area (other than the one I was previously going to).

Is it safe to drill out the well plugs and replace them with screw-in plugs? The last few q-jets I've had have had bad leakdown from the main well and front (fuel inlet) plugs. I noticed the last place I was sending the carbs used epoxy to seal the plugs. Is there a recommended type of epoxy to use?

 

[lurchsmalibu]

I've never had issues with bodies being untrue, fully assemble it and find a smooth surface then put down a sheet of fine grit sand paper with some water on it and move the carb in small circular motions to see just how far the base plate is untrue. Should only true up the base plate if you need to, but with the thicker gasket that is used for the carb to manifold, it shouldn't leak unless it's about to break.

If you true up the other gasket sealing areas they have a tiny raised area the entire sealing area IIRC, it can be worse off than what you have now. #-o :lol:
here is some good reading http://www.circletrack.com/techarticles/ctrp_0607_quadrajet_tech/index.html http://www.highperformancepontiac.com/tech/hppp_0702_rochester_quadrajet_carburetor_tuning/vacuum_hose.html but do searches and see what is out there online for tips. 8)

 

[StreetBu]

Dont use screw in plugs, you can easily crack the base by even slightly over tightening them. Epoxy them in so they wont leak on you. As far as milling them flat. I wouldnt, use a piece of glass with 400 grit wet/dry paper on it and do as Lurch said, circular motion and check OFTEN to see how bad the low spots are. If they are that bad you'll need another one....

 

[chevybowtie]

Thanks for the tips on the glass w/ sandpaper. I'll try that out.

 

[tiedyemike8]

Check the throttle shafts for wear in the baseplate. If they're loose, it can cause tuning and driveability troubles. If you have a drill press, it's easy to install and ream bushings to resize the holes. You could probably do it without a drill press, but I haven't tried.

 

[1981Regal]

http://www.cliffshighperformance.com/

Good stuff

 

[t5montecarlo]

You can rebush the throttle shafts without a drill press. I bought a kit with a long drill that had the end milled down so it would use the opposite side as a pilot. The kit worked out great.

I got it from The Carburetor Shop in California, many moons ago.

 

[Damon]

You can rebush the throttle shafts without a drill press. I bought a kit with a long drill that had the end milled down so it would use the opposite side as a pilot. The kit worked out great.

I got it from The Carburetor Shop in California, many moons ago.

Yeah, me too. Same tool, bought from the same place many moons ago. I do it with a hand drill no problem since it's self-aligning. You're drilling aluminum so the work goes quick. I always lock-tite the new bushings in place (apply it to the ouside of the bushing before you tap it in).

 

[woody31]

LOOK UP SEAN MURPHY INDUCTIONS

 

[StreetBu]

X2!!! he did awesome work for me!