Carburetor Adjustments-How to Adjust Your Carburetor After a Carburetor Rebuild

This article will explain to you how to adjust a carburetor after rebuilding one. You can also use these instructions to adjust rebuilt carburetor after you buy one. Most of the carburetor adjustments are preset if you buy a rebuilt one rather than rebuilding one and having to find the specifications to adjust it to. After installing the carburetor on the vehicle, you will still need to check these adjustments. Although the rebuilt carburetors have been preset, they still have to be adjusted properly or your vehicle will not run, as it should.

Once you set the carburetor on the vehicle and tighten, everything down the first adjustment to this carburetor will be to the choke system. On a cold engine hit, the throttles cable a couple of times and see if the choke plate snaps shut. When it does start the vehicle up and watch the choke pull off in operation. Some carburetors have two choke pull offs operated by the engine vacuum engine. Normally after a carburetor rebuild a choke angle gage is used to adjust these pull offs. We are going to presume that a carburetor choke angle gage was not used and adjust this carburetor’s choke pull off by sight and sound.

As the engine starts and is, idling high because of the cold engine check and adjust the carburetors fast idle speed settings. Adjust the fast idle to specifications. With a Phillips head screwdriver, adjust the choke pull off by turning the screw clock wise to lean the mixture out. Turning the screw counter clockwise, you will be richening up the pull off setting. As the carburetor is warming up after a couple of minutes hit the carburetors throttle once and your choke linkage should kick down to your base idle speed setting. Adjust your carburetors base idle speed to specification and at this time adjust your carburetors air conditioning idle by turning on the air condition and setting that ac idle to specifications.

Carburetor adjusting is a skill that can be learned over a long period. I understand carburetors are no longer installed on today’s cars but I have seen many older cars still on the roads today. The last carburetor adjustment to do now is the air fuel mixture screws or screw depending on the type of carburetor you have. This carburetor adjustment is what you can call fine-tuning the mixture screws. Turn the car off and screw each carburetor mixture screw all of the way in making sure not to over tighten them. Now with your carburetor-adjusting tool screw both screws all the way out three complete turns. Start the car and slowly turn the carburetor adjusting screw in a quarter of a turn each time until you hear the engine begin to lower its base idle. Turn the screw back out slow enough to get that last little RPM rise and stop. Do the same to the second carburetor screw if equipped.

I hope this article will assist you in learning how to adjust your carburetor after a carburetor rebuild or after replacing your vehicle with a rebuilt carburetor.




Adjusting The Air Fuel Mixture Screw