R21 carb

[Greeney in France]

As a runaround I have a R21 1700 manager. It recently started to chug on acceleration which clears with more choke. I knew it was vacuum leak but couldnt find it in any pipework, I then found out that a fault with the carbs on the 21s is that the base warps and lets air in
Is there a "fix" without going to the expense of a new carb
Thank you

 

[malcolm]

Hermitite Red (or a similar instant gasket material that isn't silicone based) would surely save the cost of a new carb if the leak is at the gasket. Can also save the cost of a new gasket for the really economically minded among us. :smile:

 

[Greeney in France]

I thought of this but didn't know whether it would behave like a suitable gap filler I also thought of maybe making a base gasket out of rubber to give a little but not sure

 

[bantamallan]

grind the flange down a bit on some wet& dry paper but do not thin the flange too much. A new gasket which is probably a bit thicked than the old one will then solve the problem. Sealer would help too
Allan

 

[Steve Hennessey]

I've done loads of these in the past. Strip carb down, pack venturi and float bowl etc with rag. Use a straight edge to determine how much metal needs removing, use a file to remove the metal by drawing it diagonally over the flange. Test with the straight edge until it is flat. Get a piece of plate glass and use coarse grinding compound on the flange whilst rubbing the carb body in a circular motion on the glass to get rid of the file marks. If you want to be very fussy, use engineers blue to make it perfect. Give the carb a good clean with cellulose thinners and blow clean with an air line.
This is a permanent fix and it won't leak again.

 

[Greeney in France]

Thank you very much all I am going to tackle next week