Occasional Fuel Leak from Vent Hose at #3 Carb

Information and questions on GL1100 Goldwings (1980-1983)
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Occasional Fuel Leak from Vent Hose at #3 Carb

Post by Josterhage » Tue Oct 31, 2017 10:48 am

I have an occasional fuel leak from the connection for the vent hose where it attaches to the #3 carb on my 81 GL1100. This appears to only happen while the bike is parked, it was cold the night before, and I forgot to shut the petcock off. Once I have shut the petcock off and the temp warms up the leak stops. Looking for possible causes.

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Re: Occasional Fuel Leak from Vent Hose at #3 Carb

Post by Mr moe » Tue Oct 31, 2017 12:14 pm

The "vent" hose is actually a drain hose to drain any excessive fuel in the carb.
The needle valve on that carb may be leaking causing the high level of fuel.
Or possibly the float level is set too high on that carb.
Always, always shut fuel tap off when not in use.

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Re: Occasional Fuel Leak from Vent Hose at #3 Carb

Post by RBGERSON » Tue Oct 31, 2017 6:18 pm

I didn't think there were any "vent/drain hoses on Gl1100 or gl1000 carbs but #3 does have a vacuum hose that goes to the pulse generator. if the carbs leak the gas goes into the cylinders and then oil pan.. shouldn't have to shut petcock off if the carbs are working correctly but it is a good safe guard in case they are not. As one can bend a rod if you get hydrolocked..


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Re: Occasional Fuel Leak from Vent Hose at #3 Carb

Post by Overdog » Wed Nov 01, 2017 5:08 am

I was thinking the same thing....no overflow tubes/hoses. A leak at carb #3 could be from the accelerator pump. If the diaphragm fails gas will travel up the shaft and leak from the carb body....I had this happen. The symptoms were different though....I kept smelling gas when I was riding but couldn't find evidence of a leak. After some time it got bad enough that the carb was wet. I was looking at the carb with a flashlight when I twisted the throttle...that's when I spotted the exact problem

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