Author Topic: Carb leak help  (Read 124 times)

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Offline frenchy51

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Carb leak help
« on: September 18, 2019, 05:12:08 am »
My '76 CB750F starts and runs great but when it sits for any length of time if I don't shut off the petcock I will have a puddle of gas under it. It appears to be coming from a vent hose. Any cures short of a carb rebuild? Thanks

Offline Scott S

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Re: Carb leak help
« Reply #1 on: September 18, 2019, 05:21:43 am »
 Turn off the petcock when you park it.
'73 CB500/550
'71 CT70
'14 Triumph Scrambler

 and too many projects...

Offline Doobie

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Re: Carb leak help
« Reply #2 on: September 18, 2019, 06:22:56 am »
The owner's manual recommends turning off the petcock. If it were me and I didn't know the history of the carbs, I'd rebuild them for peace of mind. I don't want to see a puddle even if I forget to turn off the petcock.

Offline Sigop

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Re: Carb leak help
« Reply #3 on: September 18, 2019, 07:24:06 am »
Frenchy51, could also be stuck float valve. Alot on here about that and pretty common for old tank garbage to get caught under the needle.  But your post reminds me that when I started to get my bike running again my carb was leaking unmercifully. Did a Google search and found SOHC/4.  Been an addict and consumer of this site ever since.  General thank you to all here for the collegial and contributory spirit of members.
CB750 K3  Original Owner and Operator