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850 gone down already??

Hearing Polaris has ordered thousands of 850 motors due to this issue. Also hearing not "if" but "when". Hoping its just hearsay, but in the past this source has been reliable. Also hearing they are running thin on motors already and asking certain dealers to do a bottom end rebuild. Ouch.

Does anyone have over 600-700 hard mountain miles on one of these yet?

Sounds like if true about PI ordering thousands of motors, they plan on taking care of all of us. We would have to assume they would correct a failure issue before putting new motors in sleds.
OR, they need thousands of motors for next years builds which would be underway soon. JMHO
 
Sounds like if true about PI ordering thousands of motors, they plan on taking care of all of us. We would have to assume they would correct a failure issue before putting new motors in sleds.
OR, they need thousands of motors for next years builds which would be underway soon. JMHO

I had this same thought. They are going to run this motor for awhile, and so long as they worked the issue out (which you have to assume they did) why not order a batch of motors now? Seems smarter than not...

So yeah, who knows. I just want to see a few motors get some serious milage on them.

Even if there are 1000 failures that still means you have a 90% chance yours is fine....
 
realistically I don't think there's more than 100 840 down because these news travel very fast as we've seen already And there's like 10 cases reported here?

So that's like 1% of the 840 with major engine issue, to be extremely sure I'll say there's 2% of the 840 SOLD who went down. I know some 840 still haven't seen snow but we don't have those numbers.

I'm sure Polaris like these numbers as all other manufacturers would....while snowest is panicking with the same data.
 
Nine2Nine

Ride it like you stole it and make sure a buddy of yours has a 600 RMK for backup......you'll put 2000 worry free miles before even considering a top end. :thumb:

OTM

BTW....50cm's this week me thinks.....
 
Do you have any picks of the inside of the top half of the case and did the center bearings look dry? I’m just trying to figure out how they were planning on oiling these. The ctec 800 has the same seal set up but they have oiling holes through the top of the case into a hole in the bearing to fed them. By the looks of what I can find polaris is relying on oil to get down between the crank web and bearing.
The Polaris Liberty engines also had the oiling hole that also promoted air flow into the center bearings and the inside bearing on the mag side. They left out the oiling hole to the PTO bearings and that bearing seemed to go first, consequently. 1/4" diameter hole. A little depression in the crankcase that pooled oil, occurred at the top end of that oiling hole, in order to catch more oil to funnel down the hole. The engines without the holes would last about 4000 to 4500 miles in an RMK, until a bearing blew. But the four outside bearings could be replaced at any time, on a work bench.
 
850 testing just got back

Well people, I have not had time to do any catch up reading but thought I would throw out a post before I do some reading.

Took the new 850 with zero miles we had the motor out of and did all the updates.

What was done to the motor.

#1 - HG7 polish honed the cylinder ( stock OEM pistons )
#2 - lock ringed the PTO BEARING
#3 - machined 2 grooves into the upper case half @ the 12 o clock location ( this eliminates any chance of the banjo fitting plugging with silicone, also oils the * both * center bearings with oil exactly where they need it )
#4- shorten rod banjo fittings.
#5- installed our billet head ( stock size hemi domes ) never detonated
#6 - also had our heaviest Billet clutch cover ( with no holes ) on the sled.

Ok it was really really warm out ( 35 to 45 degrees ) in the middle of the day.

( fuel used ) - pump premium with NO premix. ( gold ves oil )

I unloaded the sled at Lakewoods early morning before everyone was ready..... when I got on the lake 100 feet away
I held the sled Wide Open throttle for at least 1 mile without letting off.

The sled went to 95 miles per hour and nosed over like I hit the choke..... I never let off. It then sat at about 75 miles per hour till I let off.

So for the next 30 miles I ran in the shoreline powder maybe 8 inches deep. And ran the throttle all over the place and circled the lake 90% of the time I had the throttle wide open let off when it nosed over just so it would come back.

I was trying to blow it up. I found out the sled acts like **** for exactly 2 hours....... ( went and refilled the sled ) it used exactly 5 gallons in 30miles... then I held it wide open on the lake and it went 105 I held it for almost 2 miles. (It does a few weird things during extended full throttle ) almost like it resets for a sec .... noses over @105 and will not go past that.

Does weird cutting out ( seems like by design )

I had the sled WOT every chance I got.

At 2 hours the fuel cunsumption fuel mileage over tripled and the sled got the best mileage in the group.

Day 2 more of the same except the sled went 107......

Mid range power is pretty impressive..... 12 sleds in the group almost all 800 Polaris axys’s Sleds

At a dead stop or rolling the 800’ s do not really have a chance the 850 literally drives awayfrom them all with easy by a long long ways.

I heard the sled needs 10 hours to get past double oil.... and it DRINKS OIL ! Used over twice as much as anyone else.

I was just short of 10 hours on the motor and never got to see what it was like on top end speed with normal oil delivery.

What is my opinion of the 2019 850 Indy 129 ...... ?

I love it !
It pulls your arms really really hard
Way smoother then an 800 motor with the light weight crank.
Runability after 2 hours was pretty darn good ... I expect the after 10 hours performance to even better.
Sled ran cooler then all other sleds in the group except one ( and that was a 2016 PROX 800 with a Ride cool head with the bigger thermostat )

That sled ran just over 100 degrees and the 850 ran 108 to 111most of the time.

Almost all other sleds were running 130 plus...... unless idling or on super hard pack / dirt trails.

I really tried to hurt the motor with the changes we made to see if there was a weak link.

I see this motor being a real leader in both mountain and trail. I really do love the motor.

This was the maiden voyage.... we have 3 more trips planned in the very near future those will be alot more miles. With lots
Of high speed running.

We will do a cylinder leak down after each trip.


Dan
 
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So I was wrong..... At 10.7 hours on my 850 The PTO oil line did not pop off. The oil line that feeds the water pump cavity popped off. I was able to personally inspect the crank bearings and other engine internals at the dealership, and was happy with how the bearings felt and top end looked. Still no difinive answer as to why the cavity built pressure and blew the line off. Dealer tested both entry and exit check valves, and both flowed freely. No evidence of excess sealant inthe cavity.... We do not have Polaris marching orders yet as to how to procede. I will update once a proposed solution arises. EDIT: The waterpump cavity was full of injector oil upon dis assembly according to the dealer.
 
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