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I have a 95 xlt and it the engine dos not look like it was ever rebuilt, so i thought id check compressions, needless to say its not the best. The machine runs tip top though, i really dont want to touch it, but im thinking a fresh top end would be nice.

In your opinion do you think the cylinders would need to be bored out? Or could i just do new rings and pistons and hopefully the compression will restore? And whats the chances of the new top end blowing out the crank? Like I said this machine is pretty relaible, I replaced the track and rear suspension bearings/shocks and stuff last summer, as well as both clutches this winter, so I will be keeping it for a while. It always starts no more than 3 pulls (most of the time 1). Should I Rebuild the top end or just leave it?! I'm more concerned about the boring it out, I think it would just be worn out rings, and new one's should bring it back to proper levels, I can replace them myself.

Any thaughts are appreciated. Thanks
 

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I have a 95 xlt and it the engine dos not look like it was ever rebuilt, so i thought id check compressions, needless to say its not the best. The machine runs tip top though, i really dont want to touch it, but im thinking a fresh top end would be nice.

In your opinion do you think the cylinders would need to be bored out? Or could i just do new rings and pistons and hopefully the compression will restore? And whats the chances of the new top end blowing out the crank? Like I said this machine is pretty relaible, I replaced the track and rear suspension bearings/shocks and stuff last summer, as well as both clutches this winter, so I will be keeping it for a while. It always starts no more than 3 pulls (most of the time 1). Should I Rebuild the top end or just leave it?! I'm more concerned about the boring it out, I think it would just be worn out rings, and new one's should bring it back to proper levels, I can replace them myself.

Any thaughts are appreciated. Thanks[/b]
what are your compresion numbers ,the XLTs as with many Polaris models are not high compression engines,if it starts and runs well why fix what aint broke,if its running terriibly if one cylinder is way lower than the rest sure
 

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Well if you put new rings in then you will most likey still have the verticle lines in the cylinder, it will help a little bit to put new rings in but untill you get the horizontal lines in the cylinder then it wont be as good. But i dont know if boring it out will blow the crank.
 

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Discussion Starter #4
one cylinder was around 70 , one was about 90, then the other was 120 :\ It runs great.
 

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one cylinder was around 70 , one was about 90, then the other was 120 :\ It runs great.[/b]
wow yeah if all your numbers are good,and you have verified more than once with the same amount of pulls each time then YES id definatly be pulling down the top end,also if its original with that kinda milage id be dropping a new rebuilt crank in ,while it was down
 

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wow yeah if all your numbers are good,and you have verified more than once with the same amount of pulls each time then YES id definatly be pulling down the top end,also if its original with that kinda milage id be dropping a new rebuilt crank in ,while it was down[/b]

Yeah, those numbers are too far off. If your clearences are correct still with new stock pistons and rings, then all you would need to do is hone before you install new pistons and rings. If you do plan on keeping it for a while the crank might be worth doing as well. Nothing worse than rebuilding the top end and having the crank go out shortly after. Been there done that. You might be able to have yours rebuilt, or exchange it.
 

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if you put new rings in a old cylinder there is a good chance that the cylinder is not round anymore.the old rings have worn to fit thou.putting in new rings that are perfectly round are not going to seat well at all.if the cylinder is tapered at all it could also break the rings at high rpms.jmo
 

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i have a 93 xlt,i had it rebuilt in 2005.my compresion is 115 all the way across.so if that helps ya at all there ya go.i would say 70 is low for sure.thats about where mine was sitting when i sent it off for rebuild.it was running really good at the time but i figured why take a chance.with my luck if i would have left it,it would have went kaboom on the first snowfall in the 06 season.
 

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Well, since I have some past expecience with this exact motor. I might be able to help a little more with your decision.

First I must ask if you really want to keep this sled for a while longer, I rebuilt my scr monoblock xlt motor and the next year bought my 600 HO CFI and will be patting myslef on the back for the best decision I have every made. The xlt chassis just plain, well... sucks, sorry to say it, compared to this IQ chassis, heck, the rev chassis doesnt fend well at all against the IQ chassis. Why do you think ski doo is coming out with the rev 2 chassis that nearly matches the IQ? My dad is an avid ski-doo fan and was very disapointed that the prototype rev 2 chassis rode exactly, and he even said a little bit worse than the IQ. I know I am going on a tangent that doesnt follow you origional post I am just trying to tell you it would be better for you in the long run to save the money and buy a leftover IQ sled.

But...

I know how addicting the xlt motor can be, specifically if you have a 95 xlt motor. The fact that you have a 95 almost makes it worth the money spent rebuiling it, in 95 the cranks are were much stonger than the later years.

I debated for 2 years on rebuilding the xcr or build a new seld, and I will say that I am 110% happy about buying an IQ. But.... I also rebuilt the top end on the xcr. So I know you might not have the money to spend on a new sled, and you might not ride as much as I do, I really dont know and will leave that decision to you.

As for actually making the decision on rebuilding the xlt.

First... your compression numbers definatly show that you need a top end rebuild, and my guess is that you listed the compression numbers in order of PTO: 70 psi, middle cyl: 90 and MAG: 120.
That is a suprisingly common combination for a tripple sled. These XLT's actually run about 100 psi on a fairly new or rebuilt motor. But as always on a sled it seems that the PTO side will wear more due to the extra load it sees. Your compression numbers are honestly exactly what I would expet for 11,000 miles.
second... even though its obviously a strong running sled to reach 11,000 miles, those compression numbers are getting to far apart.
Third... should you rebuild the top end? Well.... I rebuilt mine, they were not out of round so we just had it honed out. Which you must do with new rings regardless if you got it bored out or not, otherwise you will end up with pretty much the same problem you have now, in a short time. Also you need to decide if you are going to do the rebuild or if your going to have someone else do it. Because with a tripple cly mono-block, your going to have a frustrating night putting those pistons in the block. If you think about it you have to put in the first piston, which is really easy, then slide the block down to put in the second piston, then turn the crank 1/3 and nearly let the first piston fall out of the block while you try to put in the third piston, You quite literally only have a piston rings depth to work with while trying to get squeeze in a ring and not let another one fall out. My dad and I couldnt get it to work without one other set of hands there. It took 3 people 4 hours to get the piston rings compressed while turning the crank and making sure the other piston didnt slide out. If these were individual block motors, it would be simple to slide 1 in and bolt it down, then move the next, and do the same, and then do the last. But on a mono-block you have to try to do them all at once.

Now dont get me wrong, it is worth doing if you want to keep the sled, but make sure you have a 14 year old kid around with tinny hands to reach in and try to compress the rings while you hold the other pistons in the block.

God, now that I have made somthing simple into somthing entirely to long, here is the simple question. Do you really want to keep this sled or not?

If its not worth it then get an IQ, I gueruntee that your going to thank me until you die.

If you really do want to keep the sled, then with the miles you are at and the compression numbers you are showing then you really almost need at least a top end rebuild. But if your putting that kind of money in a sled that you really want to keep, send the crank case to SLP for the toughboy rebuild on the crank, it will more than likely be worth another 10,000 miles on the sled, not to mention at that point you will have a classic sled that you ride on the trails. Thats like seeing a 1980 sled on the trails today, doesnt happen much but you give the guy that rides it a thumbs up because its cool that its still running, and its a cool classic sled. As far as the pistons and rings go you should buy a Polaris shop manual that details the cly round specs and have a machine shop inspect the cyls to see if they will be worth just honing and putting in new rings, otherwise you need new pistons and a bore job on the block. And if that is the case I highly doubt that you would wreck the crank just because you bored it out, but with the Fuji tripples, your likely to wreck a crank bearing somewhere.
 

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Discussion Starter #10
Thanks for the reply. I really don't care for the REV style chassis in general. If anything ill probably look for a 98-2001 mxz if I upgrade, or similar polaris in that class.

I try to make this hobby/sport as cheap as possible, I am not one to spend $7500+ on a sled. I just dont drive enough, and don't mind doing repairs myself.

I will remove the heads on it in the summer and see what the walls look like. I will probably proceed with 3 new pistons rings for the time being. And to answer your other question, I do all this work myself. I only paid $1500 for this sled 3 years ago, and doing a $600+ rebuild (if i do the crank) just does not make sense....


As it is right now me and my dad have 86 indy 400 and 95 polaris 600 and they already look vintage on the trail. What ever happened to 'keep it simple smart guy'? :)
 

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hey steve i think your right on the vintage thing,i really feel that way myself with our 2 93's on the trails. but i think it cost me just shy of 850 bucks to get mine done at the dealers in the off season in seaforth. they did a great job and they did a complete rebuild. it sounds like you think the same as me. even if it costs ya 1000 bucks you will still only have 2500 bucks into the sled and your good for another 10+ years of riding it. imo your still way ahead of the game.i spent 1300 on my sled to buy it,i put another 1500 into a complete rebuild, new track,new plastic skies,plus alot of other stuff.i have now put almost 5000 miles on my sled without a lick of trouble. i can keep up with all my buddies and their 600 to 800's no problem. so i feel for 2800 bucks i'm doing great. everytime i want to go for a ride its out to the shop 2 pulls and lets go.so ya i can see putting a grand into it,you will still be saving 5000 bucks.and the guy that just spent 7500 bucks will still get the same mileage you will out of his sled.the way i see it 5000 bucks will rebuild that sled 5 more times and you will be an old man that probably can't ride anymore,and letting the grand kids run it around the house anyway lol.
 

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hone it and rings. done! cheap too! if you aint gonna hone it dont bother! the rings wont seat properly. you might have good compression for about 500 miles, then it will be right back where it started from. probably dont need to bore it unless the lower comp. cylinder is scarred in some way. as long as the bores look saveable just hone it and buy some rings and a gasket set. a hone is a cheap tool, and you will always have one for your buddys to borrow then!
 
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