2002 GTI 717 Piston Seizure Troubleshooting

[esarchenko]

I just picked up a couple of older 2-stroke skis, one of them a 2002 GTI with the 717. It ran well on the hose, I also tested compression and had 140 in both cylinders. I took it out to a nearby lake to test it in the water my brother was riding the GTI, and we got out past the no-wake zone, and that ski shut down after 2-3 minutes. I had originally thought that the battery died and there was a problem with the charging system. I towed him back and took the skis home. Once we got home I charged the battery for a few minutes and the starter was clicking and the engine was seized after I waited a few hours and came back and it would turn over again. I did another compression test front was 135 and the back was 90.

I know that I need a rebuild but I would like to figure out what caused this in the first place so it doesn't happen again. It had Amsoil from the previous owner in it. My inclination tells me that it overheated and the piston swelled and moved freely after it cooled off.

I attached a screen shot from the troubleshooting section of the service manual.

 

[Grim]

• Hopefully you didn't tow it over about 5 mph, or the engine will suck up water. When you did the compression did you see if anything came out of the spark plugs holes when you turn it over, before or after test? Is your compression guage reliable?
• If you plan on doing a rebuild, then I would take the head off and inspect it to see what happened to the cylinder, maybe you can figure out cause and fix it.
• Are the gauges and everything working, most of these models have a high temp alarm, if it overheated it should have went off.

 

[2strokeboy]

Id take the head off and inspect the bad cylinder to see what went wrong.

 

[mikidymac]

If it actually seized and not something mechanical that broke then the most likely causes are oil injection failure which is very rare or lean from lack of fuel (dirty/faulty fuel system).

 

[esarchenko]

• Hopefully you didn't tow it over about 5 mph, or the engine will suck up water. When you did the compression did you see if anything came out of the spark plugs holes when you turn it over, before or after test? Is your compression guage reliable?
• If you plan on doing a rebuild, then I would take the head off and inspect it to see what happened to the cylinder, maybe you can figure out cause and fix it.
• Are the gauges and everything working, most of these models have a high temp alarm, if it overheated it should have went off.

Yeah, I towed it very slowly. I took the sparkplugs out immediately after I noticed it wasn't turning over and looked at the pistons, I didn't see anything nothing came out.

I plan to take off the head and look at the cylinder before I do anything with the engine.

This ski only has a fuel gauge and an oil light. There is a temperature sensor between the spark plugs but if it did truly overheat it must not be working correctly.

 

[mikidymac]

The overheat sensor only activates the beeper, you should always have a working beeper.

If it got hot enough to seize from overheating the paint will have turned brown on the exhaust manifold and the rubber exhaust couplers will be melted.

 

[esarchenko]

The overheat sensor only activates the beeper, you should always have a working beeper.

If it got hot enough to seize from overheating the paint will have turned brown on the exhaust manifold and the rubber exhaust couplers will be melted.

OK, I know that the beeper is working and the paint still looks the same, do you think it had to do with poor lubrication? I'll do some digging and see what I can find.

 

[BrianMoore]

Since you have a single carburetor and maybe only one cylinder bad, I'd be looking at the oil injection on that one cylinder in that case. See if the little tube cracked or something like that.

 

[Stevie96xp]

My bet would be the oil injection lines took a crap that’s what causes most engine failures