HELP! 2 dead sleds :-((

[X2Freeride]

Agreed with X2Freeride. The compression is low on both the 7 and 8 hundred but could be the gauge not giving an accurate reading. When checking compression both cylinders should be very close to each other in psi of compression and no more that a 10% difference between the two and it would be nice to see them up in the 125 or better range on both cylinders on both sleds.

Agree 100 percent with this. If test is accurate and your compression under 110 its time for a rebuild. Cylinders should be basically even compression wise up to 5 psi different is runnable but any more can result in problems.

How many times did you pull it over? Compression check cold or hot? Post your procedure when you get time.

 

[skis_n_skid]

You should have the throttle wide open when doing a compression check so you make sure to let the full amount of air in. It generally only adds about 5-7 psi tough (over doing a test without holding it open).

As already mentioned, it could be an inaccurate gauge. Without knowing if the tester is accurate or not, you can test the integrity of the rings/cylinders by doing a wet test vs dry test (a wet test is when you put some oil in the cylinder before doing a compression test). With good rings/cylinders, a wet test should give only slightly (if any) higher results than a dry test. If a wet test shows significantly higher compression than a dry test, then there is a problem.

 

[Mrs Snowrider]

Does living at a lower altitude make a difference on the test? Spirit Lake is telling us it is okay because of living in Denver. . . I wonder if we just shouldn't break them down and rebuild. . . hmm

 

[skis_n_skid]

Yes, you will get lower readings when you do a compression test at higher elevation.

 

[WestMont]

Any luck yet getting back on the snow?