compression on 600 rev

[Tyler23]

anyone know what the compresson on a 2003 600ho rev should be?? mine has about 2400 miles

[Macgyver55]

I believe that the manual says 145 to 150.

[Tyler23]

ok well mine has 127 in both cylinders. does that mean it could use a set of rings?

[Macgyver55]

Its certainly a possibility, but so is an inaccurate compression gauge. If it starts and runs ok, I would double check the gauge before a teardown. I had over 5000 miles when I re-ringed mine but it was starting to be a bit fussy starting hot. It was down to about 130psi. Other than that it ran fairly good once running.

[311Hemi]

Tyler, are you having any issues with starting or reverse?

I would tend to say that 135-145psi would be an acceptable range on that engine cold, but as mentioned it's certainly possible that your gauge is off.

Do you have access to another gauge you could test with to compare?

Was this cold engine with wide open throttle?

From what I have heard many dealerships were not re-ringing until 125 psi. Obviously the rings are something you will want to watch as they are a known issue on the 03-04 sleds. I think it was 05' when they updated the rings?

[Tyler23]

every once in awhile i have to give it some throttle when warm to get it going other than that it runs good. no problems when going into reverse. and yes i have access to another compression tester i will do that tmrw.

[311Hemi]

If you test it again tomorrow test it twice. First time run it for 30 seconds and then test it at wide open throttle. Second time run it up to operating temp (tunnel cooler is warm) and test it again. Let us know what the results are.

[Tyler23]

ok it was cold when i first did it and never did it with it at full throttle. i will get a different tester from work tmrw tho

[311Hemi]

ok it was cold when i first did it and never did it with it at full throttle. i will get a different tester from work tmrw tho

You definitely need to test it at wide open throttle, this would be standard. You may want to re-test cold with your tester to see what results you get.

[Tyler23]

alright. i got a different tester today and heres what i came up with. at cold wide open it was 127&130, after running for 30 sec it was 130&135. one cylinder was completely rebuilt prior to my owning and that is the one with a little bit higher compression. so with these numbers could it use rings or am i alright??

[311Hemi]

If you look at my post above I mentioned testing it at 30 seconds (cold) and after the tunnel coolers are warm (hot). Sounds like you only tested cold. The variance in the first numbers seems ok but the number are a little low. The second is getting a little more difference than what you want.

How many times did you pull the engine over, and did you do the same on each cylinder?

Here is a recommendation on compression testing from someone who has a good amount of experience with Doo engines:

Quote:

This is the way to do a compression test to help you determine the sate of the rings, reagrdless if your gauge is accurate or not. Start the sled and let it run for about 30 seconds and then check the compression, what you are looking for at this time is if there is a 5lb or greater difference from side to side and if there is then it is an indicator that the rings need to be replaced. next start the sled and let it run until it is at operating temps and the t-stat is open and the coolant is flowing, shut it off and check the compression now that it is hot if the compression is 7lbs ( or more ) less than when it was cold then it is an idicator that you need rings. For example the cold compression was 135lbs and the hot compression is 128lbs or less then it probably need rings and generaly if it is 10lbs less than cold it usually will need pistons also.

[Tyler23]

oh ok i missed that part sry ill do it again tonight when i get home. i pulled it 5 times on each cylinder at wide open. but ill let it run and do it again.

[311Hemi]

You can pull more time than that if you still see the gauge going up. Just make sure you do even number on both sides.

[Tyler23]

yep i know it was done moving at 5 pulls for me. i know i dont have much experiance with snowmobiles but im tring to learn. thanks for all the help guys!