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84 RX7 Mazda carburetor adjustment

Does anyone have any experience with adjusting the choke carburetor on this vehicle. Is there a secret to it?

I worked for a multi-line dealer that also had a Mazda franchise but my experience was Mazdas was very, very limited so I can’t tell you specifically what to do. However, choke adjustments on all carburetors use the same basic principles and the choke heater itself may not even be adjustable on this carburetor as the EPA did not want anyone dinking around with something they’re not familiar with.

About all I can suggest is that you buy a shop manual (Haynes, not Chiltons as the former is better) and follow the instructions in there.

I will add that my co-worker who toiled beside me handled most of the Mazdas and that he spent probably half of his at-work time wrestling Mazda RX7 carburetors. They’re complex and apparently prone to various hiccups; most due to attempts to conform to emissions regulations.

Thanks for your assistance. I have downloaded the carb manual. I have had a lot of work done so far but it still needs some more adjustment. I was just seeing if anyone out there had any experience with this. I have located a mechanic at a dealership who has some experience with first generation Mazda’s so I guess that is my only hope.

What exactly is your issue with the carburetor?

The last mechanic adjusted the carburetor rpm’s high to prevent stalling. When the car is placed in reverse it jerks.

Try and find someone with experience on these old cars. Kinda the worst, tight pollution controls made adjustments difficult. First, make sure it’s not an ignition problem, a high idle speed is used to cover a multitude of sins…

Thanks for the info. I agree. I am headed to the dealer. There is a first generation Mazda mechanic there so hopefully he can adjust it. If not I guess it is trade in time.

A lot of “carburetor problems” are due to vacuum leaks and not the carburetor. The problem comes when someone starts adjusting the carburetor first instead of checking for vacuum leaks first. One common source for stalling is the idle up diaphragm leaking. This holds the idle up for a few seconds after letting up on the gas suddenly to prevent stalling from a high vacuum.

Carburetors of this era also use two choke pull off diaphragms and when one of these starts leaking, you have drivability problems while the engine is warming up.

Thank you, makes a lot of sense. Are you a Mazda first generation mechanic? Where are you located? Can you fix my car?