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Leaking FCR


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FCR39MX on 2002 DRZ400-S

 

Symptom--

Fairly consistently, when I turn bike off (key), I will get a puddle of gas dripping from the hoses hanging by the rear shock.  Not 100% of the time, but more often than not...  Switching my petcock to OFF always cuts the flow and has allowed me to kick this can down the road for months.

 

I figured it was debris or something bad with the float needle/seat/seal, bowl was overflowing and excess was running out.  Finally got motivated to look further into this and it appears that fuel is coming out the hose attaching to the float bowl drain nipple, which I found odd. 

 

Here are my two questions--

 

1--Does the bowl drain nipple have any fuel overflow passage routed to it, too?  I didn't recall that it did.  I thought it was just a way to drain fuel without letting it drip all over the bike.

 

2--Assuming I am correct that drain nipple is ONLY for draining, what would make it drain sometimes, but not all the time?

 

I guess I could see that if the drain screw face was not 100% or tight enough or had debris in it, the head pressure of the fuel above the bowl would seep past it.  If this was the case, however, I would expect it to leak at least a little ALL the time. 

 

Any ideas?

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I agree that it sounds like a sticking float. My question is and what you guys are telling me that when a float is stuck, the overflow runs out the bowl drain nipple?

Yea.  I nearly stripped mine on the YZ250f thinking the drain screw was loose.  Same issues and ended up being debris is the needle valve.

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FCR39MX on 2002 DRZ400-S

Symptom--

Fairly consistently, when I turn bike off (key), I will get a puddle of gas dripping from the hoses hanging by the rear shock. Not 100% of the time, but more often than not... Switching my petcock to OFF always cuts the flow and has allowed me to kick this can down the road for months.

I figured it was debris or something bad with the float needle/seat/seal, bowl was overflowing and excess was running out. Finally got motivated to look further into this and it appears that fuel is coming out the hose attaching to the float bowl drain nipple, which I found odd.

Here are my two questions--

1--Does the bowl drain nipple have any fuel overflow passage routed to it, too? I didn't recall that it did. I thought it was just a way to drain fuel without letting it drip all over the bike.

2--Assuming I am correct that drain nipple is ONLY for draining, what would make it drain sometimes, but not all the time?

I guess I could see that if the drain screw face was not 100% or tight enough or had debris in it, the head pressure of the fuel above the bowl would seep past it. If this was the case, however, I would expect it to leak at least a little ALL the time.

Any ideas?

Likely the o ring that seals the needle seat to the carb body

If not that a worn/ damaged / dirty needle & seat

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