Leaking Amal 930's

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My750GT
Cucciolo - the Lil Pup
Posts: 24
Joined: Wed Feb 29, 2012 2:26 am

Leaking Amal 930's

Post by My750GT » Sun Aug 16, 2015 6:19 am

G'day All,
My Amals leak. More like seep, from every join in them. The bowl, the bowl drain and the banjo/filter. I tried Amal rebuild kits and I've made my own. Even thread tape and fibre washers don't seem to seal it up. Anybody had this issue? Am I maybe tightening them up too much and crushing out the seals?? Really not sure what the issue is. Just want to get a better idea before I fork out more money for over priced ( for what they are) rebuild kits.
'72ish 750 GT
Functional bitser
Western Australia

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abmartin
SSD900 Darmah
Posts: 358
Joined: Tue Apr 10, 2007 5:08 pm
Location: New Brunswick, Canada

Re: Leaking Amal 930's

Post by abmartin » Mon Aug 17, 2015 4:22 pm

If it's any consolation I can't get them to stop leaking on my 1970 Triumph Bonneville either although I have managed to slow the loss. Normally the banjo fitting doesn't give much problem if assembled properly. You could check the flatness of the float bowl joint using fine sandpaper on a flat surface. It is easily distorted. You could also replace the standard float bowl screws with something that actually allows you to tighten them properly. Some would say that a too-high float level allows fuel to seep through the float bowl gasket. Ideally the fuel level should be below the gasket level. There is information available that tells how to reset the float inlet valve.This may not be achievable for the horizontal cylinder carburetor however. The easiest way to cure the drain plug leaks is to find an old set of float bowls - pre-1970 - without the drain plug.

Finally, make sure the fuel taps aren't leaking. I assume you do shut them off after riding the bike. You could also turn off the fuel taps while allowing the motor to run long enough to partially empty the float bowls after you've finished your ride.

Bruce
1979 900SS
Fredericton, NB
Canada

My750GT
Cucciolo - the Lil Pup
Posts: 24
Joined: Wed Feb 29, 2012 2:26 am

Re: Leaking Amal 930's

Post by My750GT » Tue Aug 18, 2015 5:00 am

Yeah I always turn off the taps.......................................... :oops:

Sounds like a good idea, although I can never remember which way is which on those valves. Obviously down is on, but which way is off and which way reserve (if that is the other option).

I will look into adjusting the float height. I recall having a similar issue with my Holley carb on my XW.

Thanks for your advice Bruce.
'72ish 750 GT
Functional bitser
Western Australia

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