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Main Area => General GS500 Discussion => Topic started by: SuperCrw on July 26, 2009, 09:49:30 AM

Title: NEED HELP with fuel lines.
Post by: SuperCrw on July 26, 2009, 09:49:30 AM
My first post here on this forum. I just got myself a GS500E -89. It is my first bike. To be able to drive it in sweden with my new license I had to limit the bike to 25kW. To do so I took out the carbs and placed two plates in the intake.

The bike had run well before I started too fool around with it. But now after the installation fuel started to leak from the air-filter housings  drainpipe. I thought it could be because the plates caused to much pressure in the carbs and it would somehow suck gas back into the air filter. So I got rid of the plates and thought it would solve the problem but I didn't. As soon as i turned the engine off quite a few drops would drip out of the housing.

I got rid off this problem by shutting down the fuelvalve a couple of hundred yards before I stopped. But that wasn't solving the problem, only temporarily fix it. But did morning I forgot to turn the fuelvalve on and rode off. But I didn't notice that until after 30 minutes. Which means the bike was running with a closed fuel valve, it sounds like a miracle but obviously something is messed up.

I have seen some posts about fuel coming out of the housing, that it could be because oof a clogged up pipe between the carbs and the air filter housing. But I can't really understand what is wrong with the fuel valve... :dunno_white:

Would appreciate any help here. I can run the bike now with the valve turned off and it doesn't leak any fuel when I stop. So that is good, but I want to know what is going on.

Cheers
Title: Re: NEED HELP with fuel lines.
Post by: ineedanap on July 26, 2009, 01:12:31 PM
Congratulations on your first post!!!

I'm not sure if I understand how you turned it off.  I thought the 89 petcock only had On, Reserve, and Prime.

The only OFF that I'm aware of is under the tank with a screwdriver.  It's not easy to get to.  Is yours different?

oh, and welcome to GStwins!!!
Title: Re: NEED HELP with fuel lines.
Post by: SuperCrw on July 26, 2009, 01:28:04 PM
Well that could explain it, haven't really looked at what it said as I naturally thought up was off. But what would be the difference between Prime and On?

I have only been riding on a 2004 KTM bike in the army where I took my license, so still trying to get used to this older bike, which I really like.

I am going to examine how everything is connected when I disassemble the bike again later on this year. I really want to figure out why it is leaking fuel.
Title: Re: NEED HELP with fuel lines.
Post by: ineedanap on July 26, 2009, 01:35:18 PM
ON - only on when the engine is turning.  Vacuum from the engine pulls on a diaphragm in the fuel valve allowing fuel to flow.  Otherwise it's off.

Prime - always on no matter what.

Leaving a bike on prime will eventually cause fuel to sneak past the carb float, causing the carb to overflow fuel onto the ground and into the airbox.  Is that what you've been doing?
Title: Re: NEED HELP with fuel lines.
Post by: SuperCrw on July 26, 2009, 02:06:28 PM
Yeah, exactly that's is what is going on. So then basically you only have to have it om ON to operate. How will this affect the reserve? If i have prime will it draw fuel as ON will of as Reserve?
Title: Re: NEED HELP with fuel lines.
Post by: Affschnozel on July 26, 2009, 03:29:42 PM
You probably have a stuck float , something you'd want to remedy soon if you don't want gas in your oil , meantime  don't leave it on prime  :nono:

Try shaking bike side to side ,front to back  to maybe unstick it so you won't have to disassemble the carbs
Title: Re: NEED HELP with fuel lines.
Post by: SuperCrw on July 27, 2009, 02:43:45 AM
Yea, I will try to do that. Hopefully that will help, otherwise I have to open the carbs up and see what is going on. Thx for the help
Title: Re: NEED HELP with fuel lines.
Post by: Porkchop on July 27, 2009, 08:35:07 AM
Quote from: SuperCrw on July 26, 2009, 02:06:28 PM
Yeah, exactly that's is what is going on. So then basically you only have to have it om ON to operate. How will this affect the reserve? If i have prime will it draw fuel as ON will of as Reserve?

Yes, use the ON position for normal operations.  The ON position and the RES position shouldn't affect each other.  They both utilize a vacum feed to bring fuel to the carb.  The only difference is that the ON position draws fuel from a higher level in the tank.  When you have used up enough fuel to go below the ON level, switch to RES and get to a gas station.

-Porkchop