Carburetors and Tuning

There were so many types of carburetors used by Chrysler on the slant 6 and V8 engines that I can't possibly give specific info on each carb. You should get a service manual for that. But I can give some insight into rebuilding them.

You need to first identify your carb. It may be a Holly, Carter, Ball and Ball, etc. Just look at the carb body itself. Most carbs had a tag attached to it with all the important info you need to order a rebuild kit. If not, write down any name and numbers you can find on the carb. All info will be useful.

Be sure to get a complete kit. Some kits don't come with floats and need to be purchased separately. Get a few cans of brand name carb spray. If you feel the need, some parts stores sell carb cleaner in 1 gallon cans with a handy tray inside.

Ok, so you got your rebuild kit, your floats, your carb spray, your can of cleaner and your carb in your hand leaking gas down your arm, what's next? Make a note of how all the linkages are set and how they go together. Take a picture. Draw a picture. Some linkages have different holes to put them in. Take note now so you have less trouble later.

Now take the carb apart carefully one step at a time. Watch out for spring loaded screws with check balls behind them. If you miss where they came out of you will have problems.

Now that you have it in many pieces, you can put the main body of the carb in your bucket 'o cleaner for an hour or so to soak or clean every passage with the spray. Even if you soak the carb, you will have to spray all passages to clear them of debris and varnish.

Clean all the little pieces too. Make sure all the passages in the throttle plate are clear. Check the air horn passages. Check all the shafts that pass thru the carb. If they have too much play it translates into a vacuum leak.

By this time you have already opened your kit and most of the parts look familiar. Once you have the carb clean you can start reassembling the carb in reverse order you took it apart. Check the manual you bought with the specs in it to correctly set the float level.

Also by now you know where the fast idle cam is and the base idle setting and the air mixture screws are. Once you have the carb assembled and reinstalled, all these will need to be adjusted. To baseline set the air mixture screws, turn them in until they bottom out, then turn them out one and one half turn. Don't turn them in too tight. Gently until you feel it hit, then back it off.

The base idle screw. Turn it down until it starts to move the linkage, then stop. Close the choke butterfly and make sure the fast idle screw is on the highest step. Now start the car. You may have to adjust the base idle screw until the engine stays running. Check for any fuel leaks. After the engine is warmed up, make sure the choke is off and set the base idle to the spec in your book.

Now for the mixture screws. Turn them out some. Then turn them in until the idle starts to get a little rough, then back it off until the idle smooths. Double check your timing at this time. Adjust it if necessary and adjust the base idle if necessary.

Shut off the engine and wait for it to cool down. Set the choke. Make sure the fast idle screw is on the highest step on the cam. Start the engine and set the fast idle to spec.

If you have made it this far and your engine runs smooth as a kitten, then congratulations!! If your engine runs better, but not smooth, your carb may have internal problems that an overhaul can't fix and replacement is the only option. If your car doesn't run at all or pours clouds of smoke, re-read this article and start again.

Remember, get a manual! The instructions in the kit are guidelines. So is this article. The manual has photos to help the novice do a good job. I'm an ASE certified auto technician and I always use the manual just so I don't forget something. Follow the book and the tips I have here and your overhaul has a good chance of success. GOOD LUCK!

- Roger Kizer