07 XRS Problems!

[CF7SP]

Hey guys, need some help. Took the first ride on my new to me 07 xrs in the UP. Here is the starting point: stock motor, hps can, 490 pto jet, 500 mag, middle needle clip, 17.5 pilots, goodwin clutching for low elevation.

Took the first burp down a field and sled felt doggy, and could only make it to 7500 rpms. Changed clickers, started at #3 and went to #4 with no change. Went to #6, no change still only holding about 7500 rpms. So decided to continue til we got back to the truck. Made it almost 8 miles and stuck a ring, took the primary and moved it right away back and forth, dumped oil down both cylinders and in the gas to try and free ring, but sled was still only running on one cylinder.

Got it tore apart tonight and found 140 psi for pto, 143 psi for mag. dpm hose disconnected. Got the ring to unstick obviously judging from the compression. However, still only like it is running on one cylinder. Carb boots and reeds seem to be ok, however did not take reeds out completely to inspect them.

So, what could this be? ECM? Cracked reeds? Crank? I am lost, please help fellas, wanna get this beast back on the snow. Another thing, I am not sure if this would make a difference, but I did change out the handwarmers to a 2-wire off a nytro, but only spliced the handwarmer wires and used a resistor off the stock taillight system. Not sure if this would have an effect or not. If anyone has an idea, please let me know. Thanks in advance and happy sledding!

 

[2walla]

Clutching..

Did you check that the clutch was fully shifting out? Is the belt height correct in the secondary? Were the carbs clean? Are the powervalves hooked up correctly and not leaking? There are a myriad of things that can make the 07 and newer 800's run crappy.. First rided of the season- bad gas from last year and or plugged carbs, Then I would suspect the clutch. Especially since changing the clickers didn't change the RPM. Since you rode it till it siezed, I would check the crankshaft runout..

 

[CF7SP]

Belt height and deflection correct, carbs were clean before and after. All powervalves hooked up correctly. Clutch is the problem, but now it is only running on one cylinder, which would be a suspect of other things, right?? Anyone??

 

[evandaigneault]

Your knock sensor kicks on retarding the RPM's to a max of 7500.. So you could have been getting detonation from bad gas or something, which might have also led to screwing up your cylinders. Also, did you check to see if your oil pump is working correctly? If the sled is stock, 490-500 mains seems like too rich of jetting. Also, if the rave's arent working right that will keep your sled from revving up also, but it sounds like the rave's arent your problem.

Evan

 

[CF7SP]

That makes sense about the knock sensor, sled would not pull above 7500 no matter what I did...pulled the sled apart tonight to check the reeds and found metal shavings in the reed cage, so this is leading me to believe that the crank has failed...am I wrong? Thanks for the help fellas! The sled is stock, so what should the jetting be??

 

[meche]

I had a 2007 and within the first 100 miles one of the RAVE hoses fell off. There was a ski-doo bullitin to update the hose clamps. My sled acted a lot like you are describing, I felt like it was missing and it would not go beyond 7000 RPM. I'd look the RAVE hoses over real good.

 

[CF7SP]

good idea but I feel like I went thru the hoses really well, even looked on the microfiche just to be sure. We were suspecting the same thing, and reeds were also something we had thought. Thinking with the metal shavings that it has to be something in the crank...Ernie, thanks again for the help!!

 

[sledsrock]

How many miles on this motor/crank? As you know they do have crank bearing issues. How do you know it stuck a ring? Maybe the crank locked up?

 

[CF7SP]

1100 miles on a new replaced motor, under warranty. The case was not printed with a "R" on the case, however the motor was replaced under warranty (says the fellow snowester I bought the sled from) Well, it may have just been the crank locked up, but it sure seemed like a stuck ring, primary very hard to move after the sled stopped. Got better with oil dumped down the cylinders and gas. Was able to run another few miles to get it off the trail to an easier spot to load on the trailer. Did find shards of metal in the reed cage, so that is why we are pointing towards the crank...any thoughts?

 

[Concrete Mike]

If the original motor blew early in the season, the warrantied motor was
probably not an updated one and doomed to the same fate.Check your
clutches mine won't hold R's if any of the parts are worn.

 

[evandaigneault]

I have seen pics of guys rave valves sticking and flaking off parts of their piston rings and seizing their engines. The best way to tell is to pull your cylinder off and look at the cylinder walls.you can also look down into the crank bearings from there too. But to figure out if it is the crank you can check the runout with a dial indicator.

 

[lil734 doo]

Wow your compresson seems high I think you should be in the 125 range with the R moter As you no they where prone to bad cranks So my guess is crank bad again wich caused the metal shavings in the reed I do think also they where having bad boots on the reed in 07 I think that was a recall thing on the boots ask your Doo Dealer

 

[CF7SP]

Thanks guys, checking with the dealer tomorrow...hopefully something will get done! I will let ya guys know!