fuel leak

[paulf]

hey everyone. i'm new around here, but figure i'll just jump right in with my questions. this won't be the last, i'm sure.

alright, i recently sold my '02 rsv and picked up a low mileage (16k) '05 rsv. the problem with the low miles is that it's been sitting up the last year and a half or so.

well, i picked it up, rode it the 300 or so miles home. it runs great, better than my '02 did. however, after sitting overnight, my garage stinks of gas. i looked under the carbs. everything looks pretty wet. i see no evidence of gas running out of the overflow tubes.

any suggestions?, or should i just take it to the shop?

paul

[M61A1MECH]

Add at least a half can of Seafoam to the fuel tank next time you fill up and run that tank out on a good hard run. Then add the second half of the can on the next fill up.

When you get ready to park it for the night turn the petcock off and run it untill she dies due to fuel starvation.

 

That may help, but if the bike has been sitting with gas in the carbs and the gas was not treated with a stabilizer, you could have a gum and varnish built up that may require a carb over haul.

 

The Ethanol we get in the gas any more is a big contributor to carb issues on bikes that tend to sit more than they are ridden.

 

I would continue regular Seafoam treatments for a while even if the condition initially clears up with the first two treatments.

[allwx]

Sounds like a small fuel leak. There's quite a few places it could be coming from. An 05 doesn't seem old enough to be suffering from cracked fuel line, but it is possible. Assuming you've got a oem fuel pump in there, there shouldn't be any significant pressure between the fuel pump and the carbs, even with the petcock open, as the oem pump doesn't pass fuel when it isn't running. Fuel collecting under the carbs overnight therefore indicates either a small leak from one of the carbs, or in the line between the fuel tank and the fuel pump. Carbs should only leak what is in their bowls, which isn't much. Fuel from the main fuel line between the tank and the pump runs over that general area, so a small leak there (with petcock open) could dribble some fuel down onto the top of the motor under the carbs.

 

I would suggest you get it dry by riding it, and when you get home close the petcock before you kill the motor. Allow the carbs to run dry until the motor dies. Let it sit a few hours with petcock closed and see what happens. Assuming it stays dry, after awhile open the petcock without starting the motor, let it sit and see if any fuel appears on top of the motor. If things stay dry and stink-free then that should eliminate any power-off possibilities. If the leak reappears after you crank the motor, then the leak must be aft of the fuel pump, which brings you back to the fuel line between the pump and the carbs, or one or more of the carbs themselves. Each carb has a drain hole which is closed with a small screw and gasket. One of these could be loose and leaking. Or possibly you have a leak from where the carb bowl interfaces the carb body with a small o-ring type gasket. Otherwise, fuel coming out of a carb would probably be an overflow situation. But that shouldn't continue for long after the motor is shut down and the pump shuts off.

 

I have seen these carbs overflow, but when that happens the motor will start running very poorly as the overflowing carb puts too much fuel into the mix. You say it runs great, so that isn't a likely situation. Most likely you've just got a small static leak. Until you find it make sure you keep the petcock closed whenever the motor isn't running. Fume buildup in the garage could be explosive.

Edited March 29, 2012 by allwx
clarification

[maineventurerider]

I agree with the Sea Foam recommendation. I, too am on my second Venture. A few months ago I sold my '03 with 67,000 miles on it (I know,it was barely broken in), and bought an '06 Midnight Venture with only 4,000 miles on it. It ran great too, but once it was really warmed up I noticed some backfiring on deceleration and one time, as soon as I got it home and parked it, gas started to puddle on the garage floor. Of course after that I shut off the petcock whenever I parked it.

 

Anyway, I went out and bought some Sea Foam and added a full can, I believe, to a full tank of gas.I continued to use smaller amounts of Sea Foam at each fill up for several weeks.

 

The backfiring improved almost immediately and I have not noticed the fuel leak anymore. The only time I shut off the petcock now is if I'm riding my Harley for a few days and I let the Venture sit for a while. But it probably is good practice to shut off the petcock on any carbureted bike.

 

I'm guessing I had a stuck float needle or something, but I know there are plenty of guys on this site more knowledgable than me when it comes to the carbs on these bikes. I just know it worked for me, and it was a lot easier than tearing into the carbs. I still use Sea Foam in both my Venture and my Electra Glide at least once a month.

[RandyR]

fwiw, when I got my used 2000 RSV, the fuel petcock did not shut off the fuel (I presume when worn).

 

I notice there is a later eco for the petcock, which may address that issue.

[LilBeaver]

Sounds like a small fuel leak. There's quite a few places it could be coming from. An 05 doesn't seem old enough to be suffering from cracked fuel line, but it is possible. Assuming you've got a oem fuel pump in there, there shouldn't be any significant pressure between the fuel pump and the carbs, even with the petcock open, as the oem pump doesn't pass fuel when it isn't running. Fuel collecting under the carbs overnight therefore indicates either a small leak from one of the carbs, or in the line between the fuel tank and the fuel pump. Carbs should only leak what is in their bowls, which isn't much. Fuel from the main fuel line between the tank and the pump runs over that general area, so a small leak there (with petcock open) could dribble some fuel down onto the top of the motor under the carbs.

 

I would suggest you get it dry by riding it, and when you get home close the petcock before you kill the motor. Allow the carbs to run dry until the motor dies. Let it sit a few hours with petcock closed and see what happens. Assuming it stays dry, after awhile open the petcock without starting the motor, let it sit and see if any fuel appears on top of the motor. If things stay dry and stink-free then that should eliminate any power-off possibilities. If the leak reappears after you crank the motor, then the leak must be aft of the fuel pump, which brings you back to the fuel line between the pump and the carbs, or one or more of the carbs themselves. Each carb has a drain hole which is closed with a small screw and gasket. One of these could be loose and leaking. Or possibly you have a leak from where the carb bowl interfaces the carb body with a small o-ring type gasket. Otherwise, fuel coming out of a carb would probably be an overflow situation. But that shouldn't continue for long after the motor is shut down and the pump shuts off.

 

I have seen these carbs overflow, but when that happens the motor will start running very poorly as the overflowing carb puts too much fuel into the mix. You say it runs great, so that isn't a likely situation. Most likely you've just got a small static leak. Until you find it make sure you keep the petcock closed whenever the motor isn't running. Fume buildup in the garage could be explosive.

 

Great Advice!

:thumbsup2: