I did not mean what is the coating for. I meant, what are the circles on each piston with no coating on them for?
850 gone down already??
- Thread starter ANTHONY11
- Start date
Two options as I see it:
1) This is where they hold the piston to apply the coating But that is just a guess.
2)It could also be a way for them to "quickly" see if the piston is OEM vs Aftermarket via Exhaust duct inspection.
#2 sounds possible. #1 wouldn't really make sense, since they should be able to grab on the pin side.
I agree, the only reason why #1 might be possible is because the same circle in on the intake side 180 degrees apart. Kind of like forceps holding it.
The coating is LESS than .0005" thick, it has next to zero thickness. It has no ability to hold anything.
It is there to provide lubricity incase it runs into a condition where oil is not adequate it MIGHT save the piston from galling. Prob won't, but it sounds and looks good.
The rings are doing all the "seating" the skirt does not do any of this (like kind of mentioned in this thread).
The piston stops and changes direction every stroke, when this happens the piston will "thrust" against the cylinder walls. Like anything that is thrusted, there is usually more force as a result. IMO, any skirt wearing (not falling off) is a result of this thrusting which is 100% normal in any engine.
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The circles in the coating are the location on where to measure the piston Diameter.
Love this thread put 77 miles on mine today just about out of gas some trail blasting and meadow reading 8100 at 7700 ft was maximum. Late in the day I ran it pretty hard wide open for a good stretch 20 to 25 seconds in powder. Power seems good is smooth. Coming from a turbo it's hard to compare.
T
TheBreeze
Well-known member
Yep when it goes down in woods I will just give it to a yeti and call my insurance. Resale will be great with a new motor and warranty this spring when I order a new one. Another thing mine does not seem rich on the bottom has not flooded out or fouled any plugs. Also running 1.5 oz of ski doo mineral oil per gallon in gas.
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I just bought a 2016 Axys with mtntk turbo and it is a total riot to ride. I have been pretty much ruined and I dont think I could ever go back to a naturally aspirated sled. Let two buddies with 850 skidoos ride it and they have been ruined as well.
T
TheBreeze
Well-known member
I hope you meant to say the piston stops and changes direction on every stroke, ... if it is the crankshaft it must be past my bedtime!!!
from what I see on those pistons with 1/10 of a mile on them they have already made contact with the cylinder as their is scraping vertically!! either the peaks are to high { hone is to aggressive} or the dealer left air bubbles in the lines or someone forgot to lube the cylinders when they slid those pistons in, either way scary to think what they will look like in 1 mile 10X that scraping if it continues. I have honed.... well deglazed my own jugs for years and if I saw that after the first 30 seconds I would take it back apart and get the judges fixed {fresh cylinders} as I would think the clearances was out of tolerance {piston to wall} or I ruined the jug when deglazing...
GREAT QUESTION
And very complicated to answer.
My ( personal ) answer would be the 850 hands down my a country mile !
Reason is as follows. ( personal Answer )
On the 2018 800 motor I would ......
#1- would do polish Hone the cylinder so in trail form the Pistons will go 10,000 miles plus. 2500 to 5000 mountain miles.
#2 - remove the stock single OEM PTO bearing and switch it to a double Koyo set-up and machine a locker in the case.
#3 - machine 8 oil slots into the bottom of the rods
#4- remove the upper crankcase check valve and run without it.
The ( 2109 ) 850 I would ......
#1- polish hone the stock cylinder so so in trail form the Pistons will last 10,000 miles plus... 2500 to 5000 mountain miles.
#2- lock ring the factory PTO bearing and into the case.
#3- machine 8 extra oil slots into bottom of the rods.
#4- remove the center upper case check valve and run without it.
#5- machine 2 tiny groves into the crankcase area to get more oil to the 2 center bearings.
So you ask the question........ ( why pick the 850 if you are going to update both motors the same way? ) ?
The reason is the electrical system in the 850 is off the charts better then the 2018 and older 800's
The electrical system on the 2015 thru 2018 800 sleds is absolutely horse chit !!
And the 2015 thru 2108 8000 sleds have more dependability problems because of electrical demons then motor problems by a country mile.
SO MANY THINGS ABOUT THE 850 THAT ARE BETTER.
I LOVE THE 850 !!
Ohhhhhh..... I also found a few more details on the PTO crank seal that Polaris updated mid production.
I have pictures of both seals.... Big difference same part number.
Dan
And very complicated to answer.
My ( personal ) answer would be the 850 hands down my a country mile !
Reason is as follows. ( personal Answer )
On the 2018 800 motor I would ......
#1- would do polish Hone the cylinder so in trail form the Pistons will go 10,000 miles plus. 2500 to 5000 mountain miles.
#2 - remove the stock single OEM PTO bearing and switch it to a double Koyo set-up and machine a locker in the case.
#3 - machine 8 oil slots into the bottom of the rods
#4- remove the upper crankcase check valve and run without it.
The ( 2109 ) 850 I would ......
#1- polish hone the stock cylinder so so in trail form the Pistons will last 10,000 miles plus... 2500 to 5000 mountain miles.
#2- lock ring the factory PTO bearing and into the case.
#3- machine 8 extra oil slots into bottom of the rods.
#4- remove the center upper case check valve and run without it.
#5- machine 2 tiny groves into the crankcase area to get more oil to the 2 center bearings.
So you ask the question........ ( why pick the 850 if you are going to update both motors the same way? ) ?
The reason is the electrical system in the 850 is off the charts better then the 2018 and older 800's
The electrical system on the 2015 thru 2018 800 sleds is absolutely horse chit !!
And the 2015 thru 2108 8000 sleds have more dependability problems because of electrical demons then motor problems by a country mile.
SO MANY THINGS ABOUT THE 850 THAT ARE BETTER.
I LOVE THE 850 !!
Ohhhhhh..... I also found a few more details on the PTO crank seal that Polaris updated mid production.
I have pictures of both seals.... Big difference same part number.
Dan
Yes Sir..... You nailed it ( everything you mentioned is spot on )
The proof will soon show up..... And show its ugly head.
Dan
Dan: As we all know, you are covered over. But what kind of time frame and ball park cost for you to do the above mentioned on the 850? Thanks
