I recently installed a mtn tek turbo kit on a 2011 Pro with 1000 miles. I tore the motor apart to install a BMP long piston kit. One cylinder skirt was cracked so we sent it off with the pistons to get re-nicked. I installed the turbo kit and was impressed with the ease of installation and the quality of parts. The oiling system is different but seems logical. I turned the oiler up all the way with the set screw as the instructions said. I bled all the oil lines and reinstalled everything mixing some oil with the gas for the new motor. The sled made it about 5 miles and seized a pto rod bearing. Tore it apart again the rod bearing was blue about ready to come apart. Not much scuffing on the pistons. I got the crank rebuilt checked the oiler with a drill and it pumps oil. Put it back together made it about 40 miles and seized another lower rod bearing. Pulled the oil cap off and there didn't appear to be vacuum in the oil tank. The cylinders looked to have oil all over them. So here I am with a tore apart sled and not wanting to deal with this a third time. Any ideas? Sled runs great until it starts to seize the rod bearing. Have there been many oil pump failures on these sleds? Sorry so long winded.
2 Pto rod bearing failures in 50 miles?
- Thread starter sledfvr
- Start date
Running Lucas semi syn oil.
I'm thinking its an oil problem, I see 3 possible causes.
-oil pump weak
-oil cap
-mtn tek oiling system not sufficient
The sled was fine before the turbo/long pistion kit install. Other than the slop in the pistons/cylinders causing cracked skirts. Is there a more accurate way of testing an oil pump?
I'm thinking its an oil problem, I see 3 possible causes.
-oil pump weak
-oil cap
-mtn tek oiling system not sufficient
The sled was fine before the turbo/long pistion kit install. Other than the slop in the pistons/cylinders causing cracked skirts. Is there a more accurate way of testing an oil pump?
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?
Can't imagine the frustration. Don't think oil is the problem. If you tested the oiler and it flowed, then tried premix, and the cyls seemed oily it seems like its getting lubrication. Maybe some bad parts out of balance/out of tolerance? If its only the pto side and happens that fast, I'm thinking excessive heat being generated from something being out of whack. Good luck.
Jeff
Can't imagine the frustration. Don't think oil is the problem. If you tested the oiler and it flowed, then tried premix, and the cyls seemed oily it seems like its getting lubrication. Maybe some bad parts out of balance/out of tolerance? If its only the pto side and happens that fast, I'm thinking excessive heat being generated from something being out of whack. Good luck.
Jeff
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G
you had a problem and cracked skirts prior to the turbo install. the bmp pistons are what ? never heard of a LONG piston ?? long rod yes, long piston ??
anywho, its for sure a pre exisiting issue. had nothing at all to do with the turbo or the oiling. rod bearings let go for many reasons,, AIR leaks in the case are one of the biggest reasons. though air leaks on a turbo do NOT present a leak Vacum or LEAN leak under boost. they only lean leak OFF boost. On boost is a pressure and power loss but never ever a lean leak that can cause any issue what so ever.
recheck your next one for proper rod location in respect to cylinder bore. ( make sure its not side loaded.. and make sure it has side clearance on the big end. Ive had brand new cransk come in from the factory with zero rod side clearance. absolutely UN useable .. Had I not caught it prior to the rebuild they would have seaized in a short ride just like yours did..
Gus
anywho, its for sure a pre exisiting issue. had nothing at all to do with the turbo or the oiling. rod bearings let go for many reasons,, AIR leaks in the case are one of the biggest reasons. though air leaks on a turbo do NOT present a leak Vacum or LEAN leak under boost. they only lean leak OFF boost. On boost is a pressure and power loss but never ever a lean leak that can cause any issue what so ever.
recheck your next one for proper rod location in respect to cylinder bore. ( make sure its not side loaded.. and make sure it has side clearance on the big end. Ive had brand new cransk come in from the factory with zero rod side clearance. absolutely UN useable .. Had I not caught it prior to the rebuild they would have seaized in a short ride just like yours did..
Gus
BMP is the same as a "fix kit" with a cylinder spacer and longer pistons. The cylinder skirt was cracked because it had .014" clearance between the pistons. there was combustion going past the rings because of sloppy pistons and the rocking cracked the skirt. Very common with polaris since '06. I fixed that issue with the Bikeman kit and had the cylinders renicked to match the pistons. Both rod failures happened going down the trail to get to the good riding. It felt like the sled was losing power so I stopped and the rod was locking up. I'm not sure that it's oil, but there is no air leaks in the case's. I will check the next crank out, but I still don't think I've found the cause of the problem yet.
Thanks for the replies.
Thanks for the replies.
I remember a friend of mine bought a new sled and it seized up. The dealer installed new parts and it did it again. It turned out that the banjo fitting that feed oil to that side of the engine was plugged or defective and not allowing enough flow. Might not be your problem but could be worth taking a look.
two things jump out at me , change the oil tank venting system , these stock caps only vent when the ball inside is banged around. I drilled a .060 hole in the side of the nipple inside the tank so the ball was not sealing the system and pulling it into a vacuum. the second thing is don't premix , it doenst do much for the bottom end unless the cases are drilled for drippers on all the bearings. any change the motor got started dry and the pump had air in it?
M
Having the case machined or not for oil drippers really wont make much difference for a lower rod bearing, premix or not.
I would verify that you have all the hoses connected properly at the oil pump. The oil pump ports flow different amounts of oil.
If the color of your oil is blue. That could be the problem.
Red is much better.
I had a buddy with same thing, crank bearing seized in fifty miles, oil cap was problem, put your cap back on and take oil supply line off, if no oil runs out that's the issue, Polaris dealer didn't know what happened and denied warranty for slp air box, they gave it back to him in a box, the oil tank was full sitting on bench with no plug in oil line, nothing was coming out, took the cap off and it ran out right away, my 14 was same way. If you tipped cap just right it would vent, otherwise not, think about cursing down trail for 5 or 10 miles to get to where you are going, and the ball bumps the stinger or valve once in a while, idk maybe it vents 30 percent of the time? Bouncing around in trees their design definitely works better but turning 5-8000 rpm with the oil pump cavitating and no oil flowing is not a good thing
You buying the passo racing cap or???
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