Blown Up Polaris 800 Rebuild!

Finally rebuilt my 800 Pro-R that blew up at the start of last season!

[@dangialluca5254]

also you need to rdd ed flash your tps sensor to get the idle back down

[@jordanthomas2210]

I am new to the two-stroke world. Just curious to find out why a simple engine seal would end up destroying the motor.

[@tracksnwheels]

With 2 stroke engines the intake process actually draws the fuel mixture through the crank case below then into the combustion chamber above the piston. If a crank seal is leaking then then air gets sucked in through the leak on the intake stroke. This changes the air/fuel mixture causing a lean burn in one cylinder. This will run hotter than wanted plus, because 2 strokes are lubricated by the fuel mixture, you get a situation of lower lubrication combined with higher heat. Then bearing start to fail.

[@jordanthomas2210]

@@tracksnwheels Thank you for the explanation🤘

[@jordanthomas2210]

@tracksnwheels I purchased a 2016 Polaris Rush Pro s 800 about a week ago, and got burned on the deal. More than likely I will be rebuilding the motor. There are so many different rebuild kits, that I am having a hard time deciding what to go with.

[@amurgatroyd]

I used that wiseco fix kit on mine this year too. Seems good, was a great price at Royal Distributing. I’ve put about 300 kms on it. It’s just a spare sled . What do you think of the VR1 ?

[@tracksnwheels]

LOVE! the VR1. Handles like a dream.

[@whylee1377]

Hey man thanks for posting got a question i have a '13 assault 155. Thinking the bottom end is shot possibly main crank bearings. What were some of the symptoms your sled was having which led you to tear the engine down. Mine has become incredibly hard to roll over. My son who is a big guy has a hard time pulling the cord. Its not smooth, quite jerky like in 6 or 8 inch increments throughout each pull. Thanks any additional info will help. I had no time to look into it last ride and its kept up in Northern ontario not close to me.

[@tracksnwheels]

My machine suffered a rod bearing failure that was caused by a lean burn due to mag side main seal failure. The first indication of a problem was higher than normal rpm due to the lean fuel mix. Your problem sounds a lot different. Hard to pull over could be bad main bearings from corrosion or even a bent crank. Could also be something else along the power train like seized brake caliper or bearing in the chain case.

[@NathanNielson-lr2el]

Had my 2015 800 Axys Pro-S burn up a spark plug this last trip. Was wondering if you could give the Year, Chassis, and mileage, of your motor? I'm trying to figure out if I need to do top and bottom (most likely) as well as whether or not to get a core rebuild or parts to rebuild myself. I appreciate the video!!!

[@tracksnwheels]

This was a 2013 in a pro-r chassis with 12000kms.

[@Steven-re3tx]

What year,.... please. Pertaining information is very useful to us that don't like guessing.

[@tracksnwheels]

2013. Around 12000kms when the rod bearing went.

[@Steven-re3tx]

@@tracksnwheels 7546 miles. Thank you from Alaska.

[@dangialluca5254]

what was the cost of the crank and piston kit ?

[@alexbittle2900]

I got one with exchanging my crank and SP1 pistons full engine kit for $950 + my cranks shipping

[@rinatf6859]

Привет 👋 поршни с отверстиями для дополнительной смазки?

[@cfordyce2]

Hello. Great video. Where did you get the reman crank assembly from?

[@tracksnwheels]

I'm in eastern ontario. I got it from a place called Spoiled Sports. They were well known polaris dealer for many years but they have since retired and closed.

[@sandwich1guy]

I just went through this exact same issue to a T. Got a reman crank assembly from BWC Powersports. Highly recommend them, great customer service and fair price.

[@charlieolson5495]

Torque specs for bottom end?

[@tracksnwheels]

Here's a link to the manual with tourque lbs and pattern. Hope it works. 🤞 docs.google.com/document/d/1VRCaPnJk8X9Bs3p0cK8eJvQOkv3rNvrWfNk0s446ZEY/edit?usp=sharing

[@charlieolson5495]

Awesome thanks