Author Topic: Float bowl gaskets  (Read 374 times)

Offline JezzaPeach

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Float bowl gaskets
« on: May 27, 2023, 06:57:34 PM »
This will be on a past post somewhere but I thought I would share it in case useful. I left my carbs dry for a month or two in the winter, and when I came to use the bike again, they flooded from the bowl joints. I had bought the shaped gaskets about three years ago, possibly from the USA, and I think they must’ve shrunk when dry due to being Neoprene. I bought the round quality Viton ones from Julie (thank you Julie) and to sit them neatly in the groove, all I had to do was very gently stretch them a tiny amount and they sat perfectly. Happy days.
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

Offline deltarider

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Re: Float bowl gaskets
« Reply #1 on: May 27, 2023, 09:08:28 PM »
This will be on a past post somewhere but I thought I would share it in case useful. I left my carbs dry for a month or two in the winter, and when I came to use the bike again, they flooded from the bowl joints. [...]
That's why I always have my carbs in a natural state, which is wet. The only winter I had them dry, next spring I had what you described. They've swollen back to their original size, but I'm not going to risk it again.

Offline McCabe-Thiele (Ted)

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Re: Float bowl gaskets
« Reply #2 on: May 27, 2023, 10:08:33 PM »
I'm slightly confused here the carb bowl seals are they not above the normal bowl fuel height ?
Honda CB500 K1 (new pit dug out ready)
Honda CB400 four super sport (first money pit)
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Offline JezzaPeach

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Re: Float bowl gaskets
« Reply #3 on: May 28, 2023, 02:29:12 PM »
Yes that surprised me too, but I think the float valves may have stuck slightly, and fuel rose up and came gushing out from the bowl seal joints. I think maybe the Neoprene seals shrink when there is less fuel vapour around after being drained for a while, so not being submerged is not the factor. Or maybe the seals get wet and stay swollen with fuel sloshing around when the bike is ridden regularly.

I measured the fuel after doing the job and all still the correct volume once everything was functioning correctly. I wonder if the overflow outlets are above the bowl joints. AOK after dropping the bowls and fitting Viton seals. Good call I’ll leave it wet next winter, might run them off and refill before starting or better still try and ride her every 3 weeks or so

And…….oh I wish I had a bike lift…..😢
« Last Edit: May 28, 2023, 02:50:32 PM by JezzaPeach »
1972 CB500/4 K1 Gold
Wanted: my 500/4 UGP96M
from 1975-78. Garnet Brown.

 

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