Fuel delivery problem on GS300

[Anonymous]

I've put about 1500 miles on my GS since I bought it a couple months ago with 12k on the odo. 3 times it has cut out on me climbing a hill. It slowely looses power untill it dies completely. It seems that if I wait 10 minutes or so, it will start up again after many turns of the starter. Every time this has happened, I have been going up a hill in 5th gear (heavy throttle for 30+ seconds).

Two other problems that may or may not be related:

1. Sometimes when cruising on the freeway it will lose power momentarily. Then it comes back, no problems.

2. After I have been under a lot of throttle, then put it into neutral to come to a stop, it will cut out on me. I have the idle adjusted fairly high, but it seems to idle at a lower RPM in this situation and cuts.

I would greatly appriciate any advice.

-Brian

[earlfor]

You're running out of fuel. At high load, your fuel flow is less than the engine requires. If you have an inline fuel filter between the petcock and gas tank, remove it and replace the fuel line with a full length piece of fuel line.

To test flow, disconnect the fuel line from the carb inlet (leaving it connected to the petcock. Remove the vacuum line from the carb (leaving it connected to the petcock). Suck on the vacuum line. Fuel should flow in a 5/16 diameter stream.......not a dribble.......a GOOD stream. If it does not, then your petcock screen is probably clogged. You will have to remove the petcock from the gas tank to clean the screen. If you inspect the screen and it is clear and clean, then the petcock is faulty and should be replaced.

Earl

[Anonymous]

Thanx, I didn't think of removing the fuel filter. Is this a common problem?

I had the petcock out a couple weeks ago, and it looked clean.

[earlfor]

Fuel filters causing a reduction in flow is a common problem. There already is a fine mesh fuel screen on the petcock inside the gas tank, so forget the inline stuff. If there is enough trash in a gas tank to require another filter, its time to fix the tank. :-) When you had the petcock out, did you check it for flow?

Earl

Thanx, I didn't think of removing the fuel filter. Is this a common problem?

I had the petcock out a couple weeks ago, and it looked clean.

[Anonymous]

Fuel filters causing a reduction in flow is a common problem. There already is a fine mesh fuel screen on the petcock inside the gas tank, so forget the inline stuff. If there is enough trash in a gas tank to require another filter, its time to fix the tank. :-) When you had the petcock out, did you check it for flow?

Earl

Thanx, I didn't think of removing the fuel filter. Is this a common problem?

I had the petcock out a couple weeks ago, and it looked clean.

No, I didn't check it for flow. Do you just run gas through it?

Is it possible that I have a restriction inside the carbs?

[dgeorge]

If taking the fuel filter off doesn't fix the problem it could be your float adjustment. If they are set wrong it can cause those symptoms also. Just a thought, but Earl is usually right about these things

[Anonymous]

the fuel filter is almost new, if that's relevant.

[dgeorge]

Blong, if it is not the correct type of fuel filter it won't flow properly. Most automotive fuel filters won't work right with a gravity feed system, they are designed for a fuel pump system.

[Anonymous]

Blong, if it is not the correct type of fuel filter it won't flow properly. Most automotive fuel filters won't work right with a gravity feed system, they are designed for a fuel pump system.

I bought it at a motorcycle parts store. Also, I had this problem before I installed the fuel filter. When I purchased the bike, it didn't have one.

[dgeorge]

Blong do like Earl sugested and check the fuel flow. If that isn't the problem I would check the float height to make sure that they are adjusted properly.

[Anonymous]

Thanx a ton.

[earlfor]

Look at the 2nd paragraph of my first post.

Earl


[quote="blong"]]

No, I didn't check it for flow. Do you just run gas through it?

[earlfor]

If it isnt capable of the required flow rate, new or old doesnt matter. Toss it.

Earl

the fuel filter is almost new, if that's relevant.

[Anonymous]

Update and another question

So my fuel restriction got worse and I finally got some time to investigate the problem. It is definately the fuel cock. Withough the filter, when I either turn the cock to PRI or suck on the vacuum line, I only get a small trickle of fuel out of the line. I get less fuel flow under vacuum than at PRI.

Am I stuck with buying a new petcock? I took the thing apart, and everything seems clean and functional. I can't figure out why it is being so restrictive. The spring seems to be fully retracted. Maybe it is just clogged behind the filter where I cannot see.

Any input would be appriciated.

Brian

[Anonymous]

Well, problem solved...sort of. There is a plastic cone with holes in it that are turned by the petcock knob (PRI, etc.). I just left that peice of plastic out and put it back together. Full fuel flow. I just cannot adjust it from the ON position.