[GP65AT]

Hello,

after the season is almost done for this year, I would like to do some service work on my Grand Prix.
One big task would be to overhaul the carburator becaus the choke is annoying me very often.
The little piston which is moved by the round spring under the black platic cap is clamped by dirt or condensation water or what ever, and the fast idle will stay very high the warmer the engine gets.

How can I find out which type i have mounted when there is no tag number on it.
The only two numbers I could find are 1694 and 1565. But this seem to be part numbers ob the body and the cover of the carb?!

Maybe you can give me some tips how I can find it out?
Or would it be better to replace it with an Edelbrock or Holley (what I would not prefer because I would like to repair the original one)?

Thanks a lot
with best regards
Stefan