help with gs550

[Suzuki_Don]

Yeah, did that - but also realized I tested cold so will do again. Cheapest I found petcock replacement was $60. Figured I'd try the rebuild for $23 first!

I am with Tom on this, don't waste your time and money on a rebuild, just buy a new petcock (genuine Suzuki). Another place you could check for a fuel leak if fuel is leaking onto the motor is the underneath side of the tank for a split seam or pin holes. I am not convinced it is a fuel leak, there should be a smell of petrol on the head if that was the case.

The compression test does not sound right either. One would expect the #1 cylinder to be lower than the other three. But they are all extremely low. Something not right there. Do the compression test again and record the readings. Then put a tea spoon of oil in each spark plug hole and immediately do the test again and report back on any differences in the readings.

[arsprod]

I am with Tom on this, don't waste your time and money on a rebuild, just buy a new petcock (genuine Suzuki). Another place you could check for a fuel leak if fuel is leaking onto the motor is the underneath side of the tank for a split seam or pin holes. I am not convinced it is a fuel leak, there should be a smell of petrol on the head if that was the case.

The compression test does not sound right either. One would expect the #1 cylinder to be lower than the other three. But they are all extremely low. Something not right there. Do the compression test again and record the readings. Then put a tea spoon of oil in each spark plug hole and immediately do the test again and report back on any differences in the readings.

Too late! Did the petcock rebuild and voila, no more leaking out of #2 carb. One additional piece of info - all the plugs looked perfect except #2 which was black and obviously been running rich. After the petcock rebuild I also did another once over on all the carbs and reinstalled. For the first few minutes the bike sputtered and popped, I'm assuming clearing out all the crap left in the #2 cylinder. It's now running nicely - idles better than ever.

However, there's still the issue of low compression. More to come. Thanks gents

[AJ]

60 psi is extremely low. Is your compression tester the type that screws into the plug hole, or the type with the rubber plug you press into the hole?

How many miles on this engine?

I think you've done something wrong with the test.

Also, wipe your finger inside the end of the exhaust pipe. If it is wet and oily, then you have a problem. But if it's mostly dry and powdery, then you might be ok.

[arsprod]

60 psi is extremely low. Is your compression tester the type that screws into the plug hole, or the type with the rubber plug you press into the hole?

How many miles on this engine?

I think you've done something wrong with the test.

Also, wipe your finger inside the end of the exhaust pipe. If it is wet and oily, then you have a problem. But if it's mostly dry and powdery, then you might be ok.

Screw in, 27k, powdery

[AJ]

Screw in, 27k, powdery

Screw in - good.

Powdery - very good. Indicated that your oil wiper rings are working, which usually means your compression rings are good.

27K miles - not terribly high. Your compression should be MUCH higher than that.

If you removed all four spark plugs first and held the throttle all the way open while cranking the engine, then I would suspect the gauge on the tester or the fittings on the gauge before tearing into this engine.

Do you have an air compressor with a gauge? You could connect your gauge to the compressor and compare the tester gauge to the one on your compressor.

I would definitely check the engine with a different gauge before tearing into this motor. Good luck!

[arsprod]

Screw in - good.

Powdery - very good. Indicated that your oil wiper rings are working, which usually means your compression rings are good.

27K miles - not terribly high. Your compression should be MUCH higher than that.

If you removed all four spark plugs first and held the throttle all the way open while cranking the engine, then I would suspect the gauge on the tester or the fittings on the gauge before tearing into this engine.

Do you have an air compressor with a gauge? You could connect your gauge to the compressor and compare the tester gauge to the one on your compressor.

I would definitely check the engine with a different gauge before tearing into this motor. Good luck!

My sentiments exactly! The thing runs strong and I really have no reason to believe the compression is really that low. Now, to figure out why it's not charging... new post!