2012 Pro seized before 700 miles.

[mountaincat 800]

Ok so I bought this sled with 350 miles on it in February.
http://www.snowest.com/forum/showthread.php?t=370537

I turned the oiler up and was also adding a little oil in with the gas. When I got just about another 350 miles on it she locks up on me.
Well now I have the crank sitting on my bench with the lower Mag side connecting rod bearing shot! Thats just 700 miles on the sled!

Any suggestions on what caused it? I know the sled was useing oil on that last ride. The oil in the tank dropped about an inch with around 50 miles.
I thought when it happened it was going to be worse. (broken skirt)
But still I'm tired of my sh!ty luck.

 

[rmscustom]

Doesn't sound like it was using much oil but without measurements hard to tell. 50 miles for me is average 8 gallons of gas depending on conditions. Even a lean 50:1 ratio would burn 20+ozs of oil. Is that more or less than a inch on the tank? lol

What is probably more likely is that you got a 3 year old sled with super low miles on that spent a lot of time in storage and if it was properly stored every time that left a lot of time for the bearings to rust.

Or you just got a bad one.

 

[mountaincat 800]

Yeah. I also thought about the storage issue.
It was spring condition type snow with about 8" of fresh that day. I know that before I turned up the oiler, the oil in the bottle would barely drop a half inch. It was using a ratio of about 40 to 1 when I meassured on previous rides. I used approx. 7 gal. of fuel.

 

[Pro-8250]

ALL 800 PRO RMKS

We had two 2011's, and now we have one 2013, and one 2014. No issues.
I feel bad for you, and in my opinion this is unacceptable.
rmscustom, has a good point.
We start and run our sleds up to 100+ degrees every month in the off season.
And we always get the temp up to 100+ degrees before we ride.
I am not saying I am right on this, it's just what we do.
Good luck!

 

[mountaincat 800]

I agree. Unacceptable! I realize the chance I took buying a used sled with no warranty but c'mon man. Been riding cat for 24 years. My first Poo (big step for me) and I've lost a lot of confidence in new sled's the last few years. Hey, I try and keep my sled's for four to five years. I want a reliable 2 stroke sled!

 

[rags319]

Does this mean you need a whole new crank or can that bearing be replaced. Ive never had one apart. Does it look like it heated up from lack of oil. Just curious.

 

[mountaincat 800]

It diffidently got hot. Not sure if from lack of oil or from a failed bearing. Polaris shows a part number for the connecting rod for 200 hundo something. Again, not sure if that's just the connecting rod or more. Maybe someone here will know.

 

[Reg2view]

It was going to go before you bought it. Motors running synthetic oils need to be fogged, changed over to a dino oil, or at least started and run every 30 days, preferably with the oiler turned up, or pump lever pulled to WFO. That sled has been sitting for most of the last +2 years, and unless it was prepped for it, the mains and rod bearings are not gonna like it. The bearings could always be a better quality, but rust is rust, especially with low quantities of EPA compliance engineered synthetic oils they want us to run in high RPM, output engines nowadays. Rod bearings are the prime candidate IMPE. They will usually start to lose some HP in the minutes before they lock up or put a hole in the case from the port timing getting hosed on the bad cylinder.

 

[M8Chris]

This doesn't surprise me. One of my pros this year went down with 800 miles the other with 1100 miles. I warm up my sleds to 120 then shut them off to while I finish getting dressed and then let them get back up to 120 before I even take off riding. Stupid polaris and here I am waiting for a new one.

 

[boondocker97]

Don't worry, it's just a side effect of the pro being the best mountain snowmobile ever built. Snowmobiling is expensive and it is just a cost you have to live with if you want to ride. At least that is what I have heard over here.

Seriously though, tough break. Hope you can get it up and running again without too much headache.

So what is the deal with the synthetic oils and long term storage? Is the oil just too thin and runs down off of the metal more than mineral based oil. Any science to support this or just speculation? Not saying it's better or worse, I'm genuinely curious about it. I know the recommendation has always been to fog the engines for storage, even when they were all running on mineral oil.

 

[mountaincat 800]

The way this CFI motor is designed it really needs thin oil to lubricate. The fuel is injected at the bottom of the cylinders. The oil is injected in the bottom half of the case. With that design the fuel needs to go down in the case to pick up oil to lubricate the top half of the motor. The oil needs to be thin enough to atomize with the fuel. I'm not sure how that is done but I'm not very smart.

What up Chris? Atleast your not fixing it yourself.
I think we know how that would turn out. lol

 

[rmk727]

If your going to replace the whole crank be sure to get the 14 crank, seems I heard from a bird that half way thrue 12 is when Poo switch back to the Fuji cranks and few troubles since depends on when engine was put together or have Indy Dan rebuild it or someone known to be good, replace all Chinese bearings with Japanese.

 

[M8Chris]

The way this CFI motor is designed it really needs thin oil to lubricate. The fuel is injected at the bottom of the cylinders. The oil is injected in the bottom half of the case. With that design the fuel needs to go down in the case to pick up oil to lubricate the top half of the motor. The oil needs to be thin enough to atomize with the fuel. I'm not sure how that is done but I'm not very smart.

What up Chris? Atleast your not fixing it yourself.
I think we know how that would turn out. lol

Ha that is very true. But that is why I have Tanner as my in home mechanic. Hopefully next season we hook up for more then just one ride!

 

[rags319]

This doesn't surprise me. One of my pros this year went down with 800 miles the other with 1100 miles. I warm up my sleds to 120 then shut them off to while I finish getting dressed and then let them get back up to 120 before I even take off riding. Stupid polaris and here I am waiting for a new one.

What did they go down from. Piston/ Cylinder skirt broke. Rod bearing go to hell. Crank relateded.

 

[geo]

A rod bearing can fail early from rust, or maybe slight det, or maybe poor fit or material.

If you want to check your oil for rust "preventiveness" and maybe some other oil brand options, take a plate of steel (cast iron would show things quicker as well as show some of the other desirable oil qualities) , clean it with some acetone. Take a finger full of your favorite oil and make a swipe on the plate. Move over an inch and try another oil and so on with as many oils as you may be interested in.
Let the plate sit flat for an hour then put it on end and watch things happen for a summer month.

I have seen some of the early formula synthetics rust overnight on cast iron (20 + yrs ago) and haven't paid attention to them since so have no input on that topic.

MO from playing with the CFI I own is, light det is the #1 cause of early rod bearing failure. Also the #1 reason for setting your TPS.
Poor storage may be #2 but you won't know until you check the oil you use.

 

[Sxrlar]

We start and run our sleds up to 100+ degrees every month in the off season.
And we always get the temp up to 100+ degrees before we ride.
I am not saying I am right on this, it's just what we do.
Good luck!

That is exactly what I do! LOL. 2284 miles on my 2012, no issues, just changed the belt at 2100 miles.

 

[turboless terry]

The storage issues I've seen only make it a few miles.

 

[mountaincat 800]

A rod bearing can fail early from rust, or maybe slight det, or maybe poor fit or material.

If you want to check your oil for rust "preventiveness" and maybe some other oil brand options, take a plate of steel (cast iron would show things quicker as well as show some of the other desirable oil qualities) , clean it with some acetone. Take a finger full of your favorite oil and make a swipe on the plate. Move over an inch and try another oil and so on with as many oils as you may be interested in.
Let the plate sit flat for an hour then put it on end and watch things happen for a summer month.

I have seen some of the early formula synthetics rust overnight on cast iron (20 + yrs ago) and haven't paid attention to them since so have no input on that topic.

MO from playing with the CFI I own is, light det is the #1 cause of early rod bearing failure. Also the #1 reason for setting your TPS.
Poor storage may be #2 but you won't know until you check the oil you use.

Geo.

Could you please explain your (light deto) theory a little more? And please how would setting your TPS control light deto?

Thanks.

 

[AZ800]

The storage issue is bs if that's what's causing Rod bearings to go.
I haven't fogged a stored engine, any of them, in 20 years with no failures. 2S and 4S alike sometimes stored for n entire year.
Besides fogging the top end does little for the crank unless you fog through the intake which I would not do on any efi engine.
While I like my Pro, I realize it has the most fragile engine of all the mfg and I would have never paid full price for a good chance at owning a known time bomb.
If crank bearing lubrication during storage was really an issue then I'd have dead sleds and machines everywhere. MY 05 M7 has close to 3k mi, no issues, no special care other than firing it up once or twice in the offseason. My kids old sleds Both are 15-20 yrs old with real low mileage. Guarantee they have sat for years at a time in the past without being started or even properly winterized and they thrash the crap out of those things.
Poo just has issues. Period. It's a good thing they make an awesome chassis or they'd be out of the 800 sld business.

 

[mountaincat 800]

I agree with you AZ. I don't believe mine was a storage issue. So that leaves me with no oil getting to the mag side or detenation as GEO is talking about. That is why I would like to hear more from him or others that have experienced this.