: 1970 Eldorado Carb Rebuild - Part One



MrEightball
06-30-13, 09:20 PM
I rebuilt my carburetor three years ago. It is reasonable to say that I did not know what I was doing. Fortunately, I knew that. So I found a core on eBay to practice on first.

When I rebuilt my actual carb, I cleaned it thoroughly and replaced all if the gaskets and parts with what came in the rebuilt kit. All screws were put back with the same number of turns as when removed.

I was amazed by how not better anything got.

Since then, I've read Rochester Quadrajet Carburetors by Cliff Ruggles...twice.

This time, the tear down is much more involved. Installing oil-impregnated bushings. Replacing parts that don't come in a typical rebuild kit. But most of all, fine tuning bench adjustments followed by fine tuning with the engine running.

Tear down began today.

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MrEightball
07-05-13, 03:08 PM
Going to start putting the Q-jet back together today. Got the new bushings in. All of the internal parts are clean. Still some fine cleaning to do in the passages of the casting. Then...a lot of fine tuning. lol

70eldo
07-07-13, 07:02 PM
Where did you get your rebuilt kit and what extra parts did you get that did not come with the kit?
I am considering rebuilding my carb as well.
Thanks!

carnut
07-11-13, 01:35 PM
Dont forget to epoxy the well plugs under the carb main body! If not resealed, they can leak fuel into the intake manifold overnight! Common on older quadrajet carbs. I'm sure if you do a search someone will have a DIY on this.

MrEightball
08-08-13, 12:51 PM
Where did you get your rebuilt kit and what extra parts did you get that did not come with the kit?
I am considering rebuilding my carb as well.
Thanks!

I originally got my rebuild kit from a place in Canada. Actually, I bought two of them at $26 each. One to rebuild the "test" core and one to rebuild mine. I ended up not bothering to actually open the rebuild kit for the test core. I simply tore it down, cleaned it and made sure I could get it back together.

Try this place: http://quadrajetparts.com/rochester-quadrajet-parts-quadrajet-rebuild-kits-c-128_33.html. They have rebuild kits as well as mixture screws, rod hangers, etc. The one thing that just doesn't seem to come with a rebuild kit is a float. And I was once told by an old guy who seemed to know his stuff to ALWAYS replace the float. So I ordered a float. lol

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Dont forget to epoxy the well plugs under the carb main body! If not resealed, they can leak fuel into the intake manifold overnight! Common on older quadrajet carbs. I'm sure if you do a search someone will have a DIY on this.

You know, the first time I rebuilt the carb I actually did epoxy those plugs. And when I went to rebuild it this time, the epoxy was leaking. It turns out that it just can't take the heat of that 500ci engine. But the book I got had another suggestion that I did. And that was to remove the plugs completely, tap the plug holes and make custom screws from threaded stock to screw into the plug holes. And I put high-temp Permatex on the threads. According to the book, those should never leak again...ever. lol

MrEightball
08-08-13, 12:59 PM
Not the best photo, but it shows the custom threaded plugs I put in the throttle body.
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MrEightball
08-08-13, 01:02 PM
New choke pull-off. New float (the bronze kind). And that thing sticking up out of the primary needle bore is a roll of sandpaper. I sanded the travel of that and the accelerator pump. Smooth as a baby's bottom in there now. Amazing the pits and stuff that builds up over time.
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MrEightball
08-08-13, 01:11 PM
Finally back on the intake. I have replaced all of the vacuum lines coming from the carburetor. The climate control system is currently disconnected and capped off (that's a whoooole other project). And the master brake cylinder and power booster are in the process of coming off. So I have that very large port plugged on the carb at the moment.

About the time I got this done, my daughter was born. So I haven't actually had time to fire it up yet since the rebuild. I still need to make all of the on-car adjustments to the carb. The shop manually has a whole slew of them.

Prior to rebuilding the carb, I'd replaced my distributor, new cap, points, coil, plugs. Followed the manual's procedure for adjusting the timing. It ran so much better after that I could have cried. Now we'll see if I've made things better or worse with my carb rebuild. lol
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P.S. Those chrome valve covers are NOT my work. They came with the car. I have a set of originals I ordered from a salvage yard in Arizona. They have been taken down to the metal, galvanized, primed and painted. I have the new gaskets and will be getting rid of the "douche" covers as soon as possible. I can totally see some high-school kid thinking this was awesome. Except that there's no proper place for the PCV valve and they don't fit right and leak all over. I mean, I like chrome as much as the next guy, but these are super cheap junk. If you are going for aftermarket, at least get something that wasn't stamped out of recycled soda cans. *end rant*

70eldo
08-09-13, 09:25 AM
Thanks for all the info and feedback!
I ordered a service kit from quadrajetparts.com along with some more parts like those sealed replacement plugs, indeed a new float (bronze one), studs, accelerator pump and secondary valve torsion spring. All arrived yesterday so I studied the shop manual last night to prepare for the operation. I hope it won't take too long!

CaddyGas
08-09-13, 11:43 PM
Cool, glad to see someone taking time and getting to know their Qjet. I don't have a favorite carb, but I really like the Qjet.