Compression on 4-Tec 1503 engine

[nate78]

Hi
Does anyone know what is an acceptable psi for a Seadoo GTS - 4-Tec 1503 (2012). I've bought a ski with 58 hours on it. It looks great but the guy who sold it did a compression test and said its really good but I'm not so sure.

The results: 125, 125, 127.

Engine was cold. Though by the 3rd cylinder it may have warmed up a little. He took all the plugs out when being tested i.e. the gauge in a cylinder and no plugs in the others when turning it over.

My concern is that when i have turned it over at home i noticed it was smokey and smelly. And I've been told that the compression should be upwards of 135psi for a ski with low hours. Can anyone clarify?

Thanks

 

[Steven Mace]

might be a little low but they very close.. maybe try another gauge and just double check it. does it feel sluggish? using oil? much blow by? big job to just change the rings.. I would just keep riding it. as long as the engine oil filter has no metal in it.. maybe compare the top speed and rpm you get with another ski the same. that will tell you if it has low power. GUYs whats your thoughts?

 

[AircraftDoc]

Are you using the metric system? Lol.
Do another check. Spray SeaDoo perservative oil in first. Your numbers then should be between 132 and 140 PSI. If the pressure does not come up, then you may have issues.

 

[Steven Mace]

even if the pressure comes up you have issues shouldn't need oil to get pressure..

 

[AircraftDoc]

A true compression test is done when the engine is truly hot. That would hurt components on the PWC on the trailer or stand. So, a little oil helps with the engine not truly being hot. If it does not come up, then you may have a head gasket or valve leak.
If you don't have oil loss and the compression comes up. Give it an oil change and ride. Oil breaking down (needing an oil change) can cause issues.

 

[ski-d00]

I've seen compression numbers all over the place on 4tecs that run great so I wouldn't be too concerned. A better test to show engine health would be a leak down test. If it runs well and is getting to proper rpms, just ride it.

 

[AircraftDoc]

If you don't have oil loss and the compression comes up. Give it an oil change and ride. Oil breaking down (needing an oil change) can cause issues.

Like ski-d00 said, ride!