Joined: Aug 2017 Posts: 1,705 Threads: 47
Reputation:
25
Location: Auckland NZ
Car type: 36 Nippy, 31 RM, 38 Special, 24 Works Rep
Virtually every A7 I have come across appears to run rich on the std carb, aside from wear and settings I believe this has something to do with the specific gravity of modern fuels being different to the pre-war offerings available when the jets were originally sized
Black Art Enthusiast
Joined: Apr 2018 Posts: 507 Threads: 129
Reputation:
2
Location: Staffordshire
Car type: Ruby mk 2
Dennis my Ruby has always run rich.
I have tried fitting a washer under the needle valve to little effect
I am wondering whether the jets could be bigger after 80 odd years ?
The gasket you mention would lift and richen the mixture.
PS Good luck with the engine rebuild !
Joined: Aug 2017 Posts: 427 Threads: 35
Reputation:
6
Location: Garden of England
Car type: ARQ Ruby July 1936
Tiger, I purchased a Zenith refurb kit for the carb and it included a new needle valve plus 3 aluminium washers of varying thickness to fit between the cover and valve. One was the same thickness as that fitted on my carb and the others were thicker. Perhaps I should fit the thickest and give it a try.
I am also still very interested to know what affect basically blanking off the slow running jet makes to the performance of the carb??
Any ideas anyone??
Joined: Apr 2018 Posts: 507 Threads: 129
Reputation:
2
Location: Staffordshire
Car type: Ruby mk 2
When I closed off the slow running screw the engine stopped as expected.