I was trying to cure one thing (chirping in the exhaust) when another gremlin came up and bit me. I cleaned my carbs and checked the float level (2mm below rim of bowl) when I put it back together and tried to tickle gas weeped out from between the float bowl and carb body. Did some checking (bushman's article on AMAL carb) it said float level is too high. Went back and checked the float level again. Still appears right on or a little low, but ok. Then I checked the bowls on flat surface and found them warped. Lapped the bowls reassembled and still had the leak. The only thing I haven't done is new gaskets. These are 2 year old amals on my A65. Any suggestions? Thanks, Steve in Ohio
Joined: Sep 2002 Posts: 7,811Alex
BritBike Forum member
BritBike Forum member
Joined: Sep 2002
Steve, is this leakage happening on the side or centerstand? When the carbs are level (ie bike on centerstand), the float bowl gasket should not have to do anything unless the float needles are leaking or the floats are sticking. First, make sure there's no interference between the gasket and the float. Second, are you using plastic or the improved viton float needles? Finally, even if you get the top of the float bowl flat, the mating surface on the bottom of the body is probably warped. Get a nice single-cut file and dress this area to make it flat...though, again, with the bike sitting level and off, it should not leak from here.
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Well this was all happening on the centerstand. I retraced my steps readjusted the float level cleaned up the mating surfaces and put it all together again. This time when I tickled it there was not leaking and it started right up on the second kick. Thanks for the second set of eyes Alex. Steve in Ohio
The warped bowl will also allow air to be drawn through the pilot (idle) fuel circuit causing the bike not to run well at idle or just above.
Because of the air leak, the pilot circuit will not be able to draw any fuel out of the float bowl. It is important that this gasket seal not just to prevent a fuel leak, but to allow manifold vacuum to be able to draw fuel from the bowl for the pilot (idle) circuit. Important stuff!! John
This whole episode started with poor idle and some other issues. I had thought there may be an air leak, but did not have the presence of mind to think that I had issues with the float bowl and its effect on the pilot jet. Steve in Ohio