What do you guys think?

indy_500

Well-known member
I know this should go in tech talk but it seems like misc. gets 10 times the views. I took off my y-pipe to put new exhaust manifold gaskets on and this is what i found. It's the mag side piston. Still has 125 psi along with the pto side cylinder having 125 psi.
 

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snoeatr

Member
Must be Sea and Snow. Lol. As bad as it looks, its normal. If the compression is good, ride it till ya can't anymore.
 

indy_500

Well-known member
Must be Sea and Snow. Lol. As bad as it looks, its normal. If the compression is good, ride it till ya can't anymore.

polaris oil in this its whole life

that's what i figured, i'll just continually check compression till i notice a drop
 

biz

New member
That's called piston scuffing and could last another 2000 miles or 20. Funny, but I here every buddy talk about checking compression and oh it's got 125lbs and should be good, but in reality a compression test is only a gauge to use and also should do an inspection like Indy did. A 2 stoke will have pretty much full compression right up to the second it blows.

That picture shows the rings are worn to the point that there not keeping the piston away from the cylinder wall and could catch a port (exhaust 90% of the time) I've rebuild a lot of motors, let me guess 3500 miles? 2 piston and rings are a lot cheaper than a jug and or case.

Biz
 
The rings do not hold the piston away from the wall, only at the top of the piston. As your piston moves up and down it gets pushed to the side of the cylinder causing the cylinder to be wider at the bottom than at the top. The rings are only there to seal the top of the piston. The oil on the cylinder walls keep the piston off the walls and any dirt caught in between the piston and cylinder wall will scuff the cylinder. If you want a much more detailed explanation of how rings/cylinders work PM me, I used to manufacture/design piston rings and there is a ton of information that goes into that little cylinder.
 

Polarice

New member
My suggestion is to switch to the blood red Ams oil. Dominator. I've been using the VES Gold from Polaris but I'm going to switch. It may be a little more expensive but oil is cheaper than parts.

Also, put some in your tank. I usually put a shot or 2 in at the beginning of the day on top of the injection. Carbs and injectors have moving parts in them too. Oil injection can't do 100%.
 

indy_500

Well-known member
I'd also like to say that this picture imo represents the scuffing pretty well even though it's a picture.

polarice, i kinda like your idea, i think i'll do that, and i gotta clean my carbs.... plugs were looking a little lean which coulda caused this.
 

Polarice

New member
If you think that it's running lean, that brings something to mind.

I recently bought a 2007 IQ from a friend. I took it to my local guy. He's an old guy and an ex-polarice dealer. He stopped selling them around 2006 or 2007. He's an extremely "anal" guy. Which is good.

He went through the sled and found that from dealer setup, it was never correct. The oil was running lean, skis were toed in, the trottle cable to the place where the previous owner couldn't even give it all the gas. Which is good because the oil injection wasn't set up correctly.

My point is that a lot of these dealers just take them out of the crate and "gas and go." You may want to check the original setup on yours.
 

indy_500

Well-known member
If you think that it's running lean, that brings something to mind.

I recently bought a 2007 IQ from a friend. I took it to my local guy. He's an old guy and an ex-polarice dealer. He stopped selling them around 2006 or 2007. He's an extremely "anal" guy. Which is good.

He went through the sled and found that from dealer setup, it was never correct. The oil was running lean, skis were toed in, the trottle cable to the place where the previous owner couldn't even give it all the gas. Which is good because the oil injection wasn't set up correctly.

My point is that a lot of these dealers just take them out of the crate and "gas and go." You may want to check the original setup on yours.

it's a 1999 ;)
 

indy_500

Well-known member
So i cleaned the carbs tonight to find out that the 190 jet was in the pto side and the 185 was in the mag and its supposed to be the other way around. I cleaned the carbs and put the jets in the right carbs and when i start it up, it initially runs on 1 cylinder for a couple seconds than runs on 2. It's not a clogged jet, could this be a sign of the engine? (its been doing the run on 1 cylinder for 3 seconds when initially started up for awhile)
 

mikeh906

New member
Indy, my xlt's did that all the time. We would pull the head and hone the cyl. Then buy a set of coated pistons off ebay for little to nothing. Check your inj. timing marks. We would always pull the inj. off and pre-mix as the xlt had crank oil issues. You have a much better motor. Also a good warm up will extend the life of any motor, let it idle, do not rev it at all untill its very warm.
 

pistons

New member
Isn't the larger jet supposed to be on the PTO side because is runs hotter on that side? I know on the fan motors the fan side got the smaller jet and the PTO the larger. Check the service manual for sure.
 

indy_500

Well-known member
nope 190 mag 185 pto, 100% positive. I think im gonna go 195 mag and 190 pto even tho that's pretty dang rich just want to be on the safe side
 

mikeh906

New member
Carb tuning class 101, start rich, work down. The polaris jetting chart is rumored to be 2 sizes to rich, so your always safe following the chart. I always jetted 1 size lower than the chart, -10 to 10 or 20 + in the winter. In the spring I would change to warmer settings. There are other factors involved, so make sure every thing else is set correctly. I agree with the previos statement, 'the pto gets the larger jet'. Do you have the shop manual? Also you should get a clutch alignement tool. We made our own by tracing my polaris dealers on some stainless plate. Ole' Earlandson wrote many books on these subjects, tuning is not easy, and there is alot to it. Have fun! Quote of the day. Law of Logical Argument - Anything is possible if you don't know what you are talking about.
 

indy_500

Well-known member
Been running 190 jets both sides, haven't lost compression, put on over 1000 miles on it this year. It starts up on both all the time now, just needs full choke (i'm used to doing half choke for some reason).
 
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