97 GTS Problems

[97GTS]

I have a SeaDoo 97 GTS with a 717 engine that has been converted to premix and I have had to take the cylinders off cause of a couple of bolts breaking from the exhaust manifold. Before removing the cylinders my compression was 145 front and 148 back, now since reinstalling the cylinders the compression is 120 in both cylinders... I also can not get the ski to run, she will start and putter but not continue to run.

Also I have a question about what type of oil to use for my premix and what rasio to us I believe I need to be using 40:1 but what is the best oil to use SeaDoo, Prestone, Quicksilver, synthetic, TWC-3?

Thanks
Chris

 

[kicker]

Never use TWC 3 youyr motor won't last. Bobardier XPS 2 full synthetic or Quicksiver full synthetic is your 2 best options IMO.

Was there fogging oil in the cylinders when you did the first comp test?

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[LouDoo]

Since you have a 717 (no rave valves) you can use mineral or synthetic blend oil, but be sure it's API-TC rated, NEVER use TWC-4 oil.

Did you use the correct base gaskets when you replaced the cylinders? You may need to check the squish.

Lou

 

[97GTS]

Kicker, Yes there was fogging oil in the cylinders when I tested this time...
LouDoo, Yes the base gasket is correct and installed correctly...

I will look for these oils at my local dealer or shop...

Thanks
Chris

 

[LouDoo]

Since you still had fogging oil in the cylinders the first time you did a compression test, I would say the second test are the correct readings.
So the problem you are having is due to low compression. I would do another compression test, motor cold and throttle open, if you are still getting low readings, it's time for a rebuild.

Lou

 

[97GTS]

LouDoo, thank you again for the advise... I will try a compression test again this afternoon...

Also the oils that were suggest these are oils I can mix with the gas correct? I still have a half talk of seadoo oil in the oil tank for the lower unit to get oil when needed...

Chris

 

[97GTS]

Got home today and tested in compression and it was still at 120 on both cylinders and that's with open throttle but the ski started right up with new plugs and new gas (mixed 40:1) and the ski ran fine in the driveway on the hose... once I took it to the lake and put a load on the ski I could only get half throttle and the ski wouldn't rev any higher... Came home and cleaned the carb and have not tested on the lake again but the ski is like missing and or backfiring while on the hose at half or full throttle... I am going take the ski to the lake this weekend and try it again... any suggestion at this point?

Thanks
Chris

 

[LouDoo]

At 120psi you're ready for a rebuild, I would go with a reman engine.

Lou

 

[donkey]

to "clean"the carb,did you take it apart?
and does it have the grey fuel lines?

 

[97GTS]

I just did an engine rebuild a few years ago, and yes I took apart the carb and cleaned it and no gray lines...

Should I get a carb rebuild kit and try that?

Chris