compression test #'s what ya think

[ffemt]

A

 

[Team Elkhorn]

I'd be interested also. I think i've been told if your 110 or over cold not to worry? I have an old fan cooled 440 thats been 110 cold, and its been that way for years. Runs fine. I thought you were up north riding.

 

[ffemt]

Just put a post in ride board looking to go next week tues,or wed, or thurs couldn,t find anyone to ride with didn't want to ride the weekend

 

[russholio]

No engine expert here, but from what I've seen on DooTalk:

The first one looks okay for a while....the second marginal....the third might be looking at a top end in its near future, except that you say it was rebuilt only 1000 miles ago. Dunno....maybe something in the rebuild process wasn't quite right?

Not a Yammi guy so I can't answer that one.

 

[snootbiscuit]

a leakdown test is a much better way to determine the condition of an engine!

 

[indy_500]

Take a peak thru the exhaust, and intake side. If you see no scuffing run em.

 

[ffemt]

Hey Thanks for responses I'll go with the info @ my knowledge and reading any experts definitly chime in all responses welcome

 

[jimfsr]

a leakdown test is a much better way to determine the condition of an engine!

Generally only for 4 stroke engines...

 

[jimfsr]

06 600 ho sdi 5276 miles pto mag
cold 121 120
warm 139 138

07 500ss 3839 miles
cold 115 114
warm 130 129

02 mxz700 5313 miles only 1000 on rebuiled
cold 105 105
warm 114 115

94 yammi 600 6611 miles
cold 110 111
warm 120 119

Yammi is close to done, 700 is done, 500ss, got a little life yet, 600 same. Anything at 100 lbs or less is a definite top end. below 80 and it probably wont even run, much less start.

All these should be between 135-150 for a tight motor.

 

[doomsman]

Did you hold the throttle wide open when testing?

 

[ffemt]

Yes on the wot

 

[indy_500]

you sure you don't have your cold and warm mixed up? cold should be higher

 

[russholio]

you sure you don't have your cold and warm mixed up? cold should be higher

Kinda wondered that, too.

 

[ffemt]

I was thinking the same thing. I started sled for 30 secs. before testing cold with wot then for warm I let run for about 5 mins until heat exchanger were good and warm I'm baffle on that my self

 

[longtrack]

Looks like the 02 may have been rebuilt with Wisco Pistons. My experience with them is they last about 1000 Miles in a Doo.

 

[skidoo50]

2006 600sdi 8500 miles 160lbs pto side 157.5 mag side cold
Have not checked it warm yet. And this sled has not been babied. Also have not touched the motor at all!

 

[snootbiscuit]

yo jimfsr... a leakdown is a MUCH more accurate tool for determining cylinder condition, not just for 4 stroke. been doing leakdowns on 2 strokes for years!! not only sleds,but outboards also. been doing this for 27 years and I have seen experienced techs get burned with a comp. gauge, esp. if the cylinder only has minor scuffing. not saying the comp. gauge is not a useful tool, I use one quite often

 

[G]

You have no worries. Run 'em.