Leaking Fuel

[Azrial89]

I Just returned home from a deployment recently and discovered a problem with my 81 GS450L. I had left it in storage for 6 months and had a friend watch over it and drive it once a week while i was away. The bike ran beautifly he said and never once had an issue... Until i got home and wanted to go for a ride. The bike starts like a champ and runs great for about a minute or until i rev it. After that, it starts just ****ing fuel out of the breather port. I also have discovered fuel in the crank case. I have recently ordered a new petcock in hopes of fixing it. I was just wondering if anyone else would have any other thoughts on this problem. Thanks

[GSJim69]

The only way I know of the fuel to get into the crankcase is a petcock and a float needle leaking. This allows fuel to flow into the fuel bowl and overflow pouring fuel into the intake manifold.
You need a new petcock and fix the float needle problem, probably replacement.

[Azrial89]

Thanks, I appreciate the input. Just got the petcock today and im gonna see if that fixes it first, if not then onto the float needle. Thanks

[mlinder]

If the petcock is vacuum actuated, sometimes the diaphragm falls apart and you start sucking fuel down into the vacuum port.

[hikermikem]

As a rule, don't leave the petcock on PRI (prime) - that's the gravity feed port into the bowls designed to be used after the bike has sat for a long time & the fuel in the float bowls has evaporated. Always keep the petcock on "ON" or "RES". Those 2 settings require vaccum to open the diaphram, thus allowing fuel to flow to the carbs.

If your float needle valves don't seat completely, then fuel will overflow into the crankcase even with a new petcock if left on PRI.

Probably stuff you already knew, but i figured it couldn't hurt to re-state just in case...

mike

[BassCliff]

Greetings and Salutations!!

Hi Mr. Azrial89,

Thank you for your service. There's an article on my little website about Overflowing Carbs. Let me share some more GS lovin'.


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Thank you for your indulgence,

BassCliff

[Azrial89]

New petcock is in and she purs like a kitten with no leaks!! Thanks everybody

[tom203]

New petcock is in and she purs like a kitten with no leaks!! Thanks everybody

I hope I remember this when my petcock eventually goes!

[SVSooke]

I'm on my second bike that I got cheap because of bad petcocks.It seems to be a thing to check first.