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Well... that just happend.

Turboegt

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2014 RMK 800 Assault 155.

The PTO connecting rod decided it needed to see some sunlight, was tired of living in the dark, and came out of the proverbial closet.

Lame.

Photos coming soon.
 

Turboegt

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See the bluing at the bottom of the rod?

Pretty sure the main bearing **** the bed on the crank.

In the pics above you can see Mag side piston looked great. I did a compression test 5 days ago.

125 psi both cylinders.

Hind sight being what it was, there was a light whirring sound that had started over the last couple of rides.

Any chance the crank might be salvageable? lol
 

Brown Dog ADV

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Sorry to hear that....

2014 RMK 800 Assault 155.

The PTO connecting rod decided it needed to see some sunlight, was tired of living in the dark, and came out of the proverbial closet.

Lame.

Photos coming soon.
:yuck:
How many miles/hours on the motor? Other than the whirring noise, did you experience any loss of power and/or any other problems prior to the failure?
 

Turboegt

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250 miles on the top end.

70ish hours and 1000 miles on the bottom end.
 

Murph

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That sucks.

For the rebuild, Indy Specialties can probably repair the cases and look at your crank.

For sure if you rebuild, have them put a lightweight porkchop crank in there or sell one to you for you to install.

Were you on the edge of detonation in your setup? Light detonantion-- not enough to trigger the DET light/ limp mode-- can beat the crank bearings into oblivion and cause their premature failure.
 

Turboegt

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Got the engine torn the rest of the way down.

I lost a drivebelt about 200 miles ago. There was a bunch of belt material behind the PTO seal cover.

I'm wondering if that caused the seal to let some air by and caused the PTO cylinder to run lean.

Both spark plugs were a nice chocolate brown, the tune is spot on.

Running VES gold.
 

Reg2view

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A detonated belt does nothing good for PTO bearings, crank trueness. If it exploded, it could be what started a chain reaction. A PTO seal leak should have taken out the cylinder, first. But, did the PTO oiler get hosed by the belt?
 
I would think that if you damaged a crank seal and it leaned out on that side it would show a lighter tan/white on the spark plug on that side.?
I notice the holes on your Weisco piston skirts did you do that your self?
I had considered drilling my Weisco piston skirts thinking more lubrication and cooling would extend life of the cylinder tabs and prolong piston skirt ware but did not know how big or location to put them.
 
did the original pistons show any signs of detonation? for sure loosing the pto side seal could be a big part of the source of the problem. another guess is have you replaced the fuel filter and did you cycle the pump to clean the injectors at that time?
 

Turboegt

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PTO oiler is still there.

Although the PTO bearing is hosed, and acting like it wasn't getting any lubrication.

Also, the crankshaft at the site of the rod bearing on the PTO side is blue from heat.

I did not drill the pistons myself. They are part number # 2460M08500, and are designed to be used with a durability kit. They are my favorite pistons so far. I've had a set of RK Teks, BMP's (Wosners) and the Wisecos you see here. These are nice pistons.

The original pistons were wiped out by snow ingestion. Not detonation.

The reason the piston looks like it was experiencing heavy detonation is due to the rod bearing passing through the cylinder as it came apart.

All I can do is speculate as to why it went down.

My theory is the PTO side lost lubrication at some point.

Like I said it was making a whirring noise the last few rides, and was still running like a raped ape.

Parts for repair will be here this weekend. Should be riding on Sunday if everything goes as planned.

All clean and ready to go back together.

 
Last edited:

Turboegt

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I'd be done, but... the local machine shop sold me the wrong size rod bearings...

So I'm at work stoppage. Hopefully the local stealership has some in stock tomorrow morning.
 

Turboegt

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All back together! Runs like a top.

Just put 15 miles on it!

There is nothing more satisfying than assembling an engine from the ground up, having it start right up, and not having any leaks or extra pieces with unknown origins.
 

wildcard28

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Dude that sucks had a rod bearing let loose on a suposid reprable rebuilt crank dealer on Ebay, got hosed on that one, in less than 60miles it let loose and destroyed almost everything including the mod Sledhead Racing ported topend. No warrantee help what so ever ended up having to buy a BRP crate engine. First engine went cause of the Weisco pistons didn't last more than 500 miles. Anyway still have the sled runs great but I ride a 14 Pro now, Lol. Great Sled

Glad its running good now, Nice lookin sled

Wildcard
 

Brown Dog ADV

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Looks good!



All back together! Runs like a top.

Just put 15 miles on it!

There is nothing more satisfying than assembling an engine from the ground up, having it start right up, and not having any leaks or extra pieces with unknown origins.

Nice work! I'm glad to hear you got her back together and she runs. Enjoy!
 

Turboegt

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And... the ECU just went up in billows of white smoke.



So this is how I spent my night.

So far I've found a bad capacitor, fixed a short to ground on the ECU and fuel pump power circuits.

The stator is suspect right now to. The resistance is not looking to be within spec.
 
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