The ticking timebomb that is my 800r Motor..

[brahm]

The ticking timebomb that is my 07 - 800r Motor..

So I'm about at 2000miles on the motor so far fingers crossed it hasn't grenaded, but with that said the last thing I want it to do is drop on me mid season this year, leaving sitting on the bench for 3 weeks of prime winter. I'd like to start planning for the possibility of needing to replace the bottom end sometime this season. (ie setting aside enough $$$).

With that said what is the best route to go to quickly you get up and going, and if I am going to redo the bottom end who makes a good bore kit, or pre-assembled short block (or disassembled but complete short block kit).

Where should I look, and how much should I expect to spend? Is Ski-Doo extending any warranties with this known issue? I purchased my sled 2 years ago in NOV so I believe my warranty is expiring next month. I've searched around a bit but it seems like a lot of people just have there blocks rebuilt by local shops or themselves. I've never rebuilt a 2 stroke but have worked on plenty of 4stroke stuff any good resources or tutorials would be appreciated as well.

Thanks
-Brahm

 

[Seeyacop]

Well I have thought about the same thing and I think I am just going to extend my engine warranty for another season. Through BRP you can do so another year or more as long as you still are within warranty before you extend. That is what I was told anyways. It is about 600 bucks or so for another year of engine warranty and I think 750 for 2 more years.

 

[brahm]

Well I have thought about the same thing and I think I am just going to extend my engine warranty for another season. Through BRP you can do so another year or more as long as you still are within warranty before you extend. That is what I was told anyways. It is about 600 bucks or so for another year of engine warranty and I think 750 for 2 more years.

huh, just call the regular 1800 number? or is there a special number for them? That sounds like a good option as I'm still paying this thing off, the downside of course is if it does blow up I doubt the repair via warranty will be as quick as something I can do myself.

 

[brahm]

Also I've been reading two different things as to why they fail does anybody know what the exact cause is? In some places I read it sales bearing clearances, in others piston/ring/heat issues?

 

[Seeyacop]

Any BRP dealer can extend the warranty. I have talked to two different local dealers to me and they can easily accept your $$ and extend it, as long as it is still within the factory warrant. If not then there are aftermarket warranty options.

I was also told the BRP one is refundable on a pro-rated basis or transferrable to the next owner. So if you get the 1 year and sell it at the end of the season you may be able to get some $$ back. I have not seen this in writing and was just told by the dealer so I am not sure how accurate it is.

 

[Jack545]

I have been lookin at an 07 summit with the 800r. And the problem they were havin was the bearings would seize up after 100 to 300 miles causing them to spin in the bore. If you had the 800r getting past that many miles you were usually okay. But on the 07 they had an extended warranty package for those years. But that is so far what i have learned and researched

 

[meche]

I have a 2007 that I bought new, and based on everything I have read, here is my theory. It seems logical to me given the chain of events.

The water cooled bottom end does not allow the aluminum case to expand at the same rate as the moving parts. The inner race expands, preloading the bearings and causing premature bearing failure when the engine water temperature is too cold. This is why so many of the engines failed within a mile of the trailer. In 2008 Doo increased the clearance (I think by .0002") to allow more space for a larger temperature difference in the motors. I had heard a few people say with mineral oil the bearings will wear enough in the 2007 motor to eliminate the problem. The synthetic oil does not wear as fast and some believe mineral oil is the best choice for the 2007 engine. Seems like a stretch to me, but it could be possible. In 2008 when Doo increased the bearing clearance, they also require the synthetic blended oil, which by the previous theory will prevent bearing wear. My theory is the 2008+ engines were designed on the other end of the tolerance and any additional bearing wear could be a problem, and that is why they changed the oil requirement to the more expensive oil. I also think there is some evidence that at some mileage people are not seeing engine failures anymore, which from what I have been able to determine is somewhere around 2500 miles. But I do not think many people have exceeded 2500 miles on their sleds yet to fully prove that theory out. I think a huge majority of the failures occured before 1200 miles, and many right after the break in period of 300 miles when the fuel leans out and the moving parts see less cooling. I’d expect to get a lot more data this year as these motors get more miles on them.

 

[grizzlyman]

That's a good thoery! I've been looking for a sled for a couple months now, haven't been able to find the right one. Been putting it off buying an 07 due to the fact of all the horror stories, trying to find a 06, but people are crazy on there price. I just found an 07 with 900 miles on it. Motor has never been touched, and that scares me. Any opinions on this? Or should a guy stay away? Sled is in beautiful shape.

 

[CK1]

What you are saying I think is correct, only other thing to add to your comments in that the 07 doesn't have a thermostat, where the 08 does.

I have a 2007 that I bought new, and based on everything I have read, here is my theory. It seems logical to me given the chain of events.

The water cooled bottom end does not allow the aluminum case to expand at the same rate as the moving parts. The inner race expands, preloading the bearings and causing premature bearing failure when the engine water temperature is too cold. This is why so many of the engines failed within a mile of the trailer. In 2008 Doo increased the clearance (I think by .0002") to allow more space for a larger temperature difference in the motors. I had heard a few people say with mineral oil the bearings will wear enough in the 2007 motor to eliminate the problem. The synthetic oil does not wear as fast and some believe mineral oil is the best choice for the 2007 engine. Seems like a stretch to me, but it could be possible. In 2008 when Doo increased the bearing clearance, they also require the synthetic blended oil, which by the previous theory will prevent bearing wear. My theory is the 2008+ engines were designed on the other end of the tolerance and any additional bearing wear could be a problem, and that is why they changed the oil requirement to the more expensive oil. I also think there is some evidence that at some mileage people are not seeing engine failures anymore, which from what I have been able to determine is somewhere around 2500 miles. But I do not think many people have exceeded 2500 miles on their sleds yet to fully prove that theory out. I think a huge majority of the failures occured before 1200 miles, and many right after the break in period of 300 miles when the fuel leans out and the moving parts see less cooling. I’d expect to get a lot more data this year as these motors get more miles on them.

 

[brahm]

so what your saying is since i've made 2k miles i should worry so much?

 

[evandaigneault]

I got 3700 miles out of my crank on my original 07 800R motor. After that i bought a short block from DOO and with that came a 1 year warranty on the short block. DOO gave me a short block with a bad crank that was out of spec and so at the end of the season i got another short block under warranty, this time one that was in spec. Anyways, if your crank made it this long you should be good for another 1500-2000 miles i would say. However, check your compression on your top end as on the original 07 800R motors, the cylinders werent as durable as they are now and they had a tendency to lose compression quickly. I had my top end replaced under warranty at 2000 miles because the compression was crap. Once your crank goes, if you arent still under warranty, your only option will be to buy a short block from DOO because you cant get a remanufactured crank for the 800R last time i checked, and a new crank from DOO costs more than a remanufactured short block (i paid around $1500 plus labor for my short block). To get the 1 year warranty on the short block from doo you have to pay the dealer to install it, otherwise you dont get the warranty.

If you are worried about your crank now, pop the clutch off and check the runout on the crankshaft with a dial indicator. If it is over .003" you should be able to get a new engine from DOO since that is over their tolerances and you still have a warranty.

Hope that helps

Evan

 

[nor-cal]

"If you are worried about your crank now, pop the clutch off and check the runout on the crankshaft with a dial indicator. If it is over .003" you should be able to get a new engine from DOO since that is over their tolerances and you still have a warranty."

This is what I did. I had to prove to the dealer that my crank run out exceeded the upper limits of runout in the service manual (mine was .0055). Once that was done replacement was no problem. Run out on the new motor was .0025, not what I would call good by any means

BTW 670 miles on the first motor. 1400 miles on the second with no problems

 

[meche]

Evan,

Why did your crank go at 3700? Bearing issue or something else? Had you already put your Polaris or Comet clutch on? I would expect those lighter clutches to lead to a crank failure too. Ski-Doo puts the start ring on all of their already heavy clutches for a reason.

I did not know Doo would warrantee an engine that measures out of spec. Wish I had known that a couple of years ago, I would have measured mine.

 

[evandaigneault]

it has nothing to do with the clutch. Ski-Doo puts the rings on all the sleds because it is easier at the factory to just make a zillion of the same clutch and have it ready for e-start. Theres not much of a weight difference between the comet 4-pro and tra7. If anything a heavier clutch would be harder on the crank than a lighter one.

Pretty sure my crank went at 3700 miles because the bearings were done. My pto side bent and melted into my primary clutch and on the mag side it blew and oil went all into my stator ruining it. But i really ran the piss out of it.

 

[evandaigneault]

"If you are worried about your crank now, pop the clutch off and check the runout on the crankshaft with a dial indicator. If it is over .003" you should be able to get a new engine from DOO since that is over their tolerances and you still have a warranty."

This is what I did. I had to prove to the dealer that my crank run out exceeded the upper limits of runout in the service manual (mine was .0055). Once that was done replacement was no problem. Run out on the new motor was .0025, not what I would call good by any means

BTW 670 miles on the first motor. 1400 miles on the second with no problems

yeah, My first shortblock was .0055 too and i suspected problems because my rollers werent wearing evenly. I got it replaced under warranty and luckily my new short block was .0005 which is the best ive ever seen. I have two friends who had 08 XP's and one had his crank at .008 and the other at .0055 and that is on the 08 motor. So I suggest everyone check their crank runout even if they have an 08, its not just the 07 800R's that had issues. The bean counters were putting out bad engines at DOO all along and they knew it. I think DOO was also counting on people having issues after their warranty's expired.

Evan

 

[nor-cal]

yeah, My first shortblock was .0055 too and i suspected problems because my rollers werent wearing evenly. I got it replaced under warranty and luckily my new short block was .0005 which is the best ive ever seen. I have two friends who had 08 XP's and one had his crank at .008 and the other at .0055 and that is on the 08 motor. So I suggest everyone check their crank runout even if they have an 08, its not just the 07 800R's that had issues. The bean counters were putting out bad engines at DOO all along and they knew it. I think DOO was also counting on people having issues after their warranty's expired.

Evan

Mine wasn't giving me any problems that I could tell. Over the summer of 07 I got a wild hair after reading about guys having problems over the winter and started looking hard for a warranty problem. I didn't have to look to hard before I came across this.

 

[CBX]

trick to this whole thing is a good dealer. The good ones have been stepping up and taking care of guys. Even the mod motors. I know of several that were replace no problem. but if your lacking a good dealer around you, you may need to take a road trip.

 

[skidoojames151]

my 07 engine didnt have a crank issue...the connecting rod let loose and flew through the case...now i have an 08 engine and it has 800 miles and so far so good

 

[dmack]

how are you checking your runout, horizontaly or verticaly? ive got 800 miles on with no problems yet but i think my waranty expired last month.

 

[nor-cal]

dmack

here you go.

starrett 811 test indicator installed clutch bolt and turned it with a ratchet