2017 Sidewinder Spun Primary Backwards 1/4 turn

[Nickster514]

Hey guys I spun my primary backwards a 1/4 turn while i was tightening it to torque spec. Now I drove it for a mile had a knock sensor light kick on and drove it back home it was running alright, not great. I got to 10 feet away from my garage when it suddenly died. I tried to crank it over but it wouldnt crank then i checked the primary and i cannot move it forward its like it hit a dead spot it cant seem to turn past a certain point. I talked to a few people and they said the timing could be off now and that its possible that it would of ran with the timing a little off for a bit, then died. Wondering what is wrong with it and how expensive/ labour intensive it is to fix this problem. Obviously you arent supposed to turn your primary in the wrong direction but I barely turned it the opposite way. Did I screw my motor or is the timing just out of whack or both? Im hoping a valve didnt meet a piston or bend a rod but im not sure without taking it apart. Just trying to figure out who im taking this machine too or if its a simple fix. Sounds like the motor might have to come out to get to the timing not sure. Sorry for the long post but thank you.

 

[lakercr]

From your description I'd say it is most likely that you've had piston/valve contact. The valve (or valves) of one cylinder are likely bent now, and hanging down in the combustion chamber, preventing the piston from reaching TDC.

You're going to have to remove at least the head. I wouldn't expect a connecting rod to be bent, but you may have damage to the piston that will require the removal/disassembly of the engine. Take the head off first in the chassis and the path forward will be self evident.

Sorry to give you the news, but there's a slim chance I'm wrong.

 

[lakercr]

This video will give you an understanding of what has most likely happened. You'll have to click on 'watch this video on YouTube':

 

[74Nitro]

Milage?
Did you perform any other work besides putting the clutch back on?

 

[T-rav 27]

Nick this is travis with the sidewinder from the lake I spoke with ur dad I will take a look at the sled fir him

 

[Turboflash]

Doesn't sound good. Major damage. Agree with lakercr. Piston to valve contact.

 

[74Nitro]

If it did skip when it was turned backwards, why didn't it immediately lock up?

 

[Nickster514]

From your description I'd say it is most likely that you've had piston/valve contact. The valve (or valves) of one cylinder are likely bent now, and hanging down in the combustion chamber, preventing the piston from reaching TDC.

You're going to have to remove at least the head. I wouldn't expect a connecting rod to be bent, but you may have damage to the piston that will require the removal/disassembly of the engine. Take the head off first in the chassis and the path forward will be self evident.

Sorry to give you the news, but there's a slim chance I'm wrong.

I agree with valve to piston contact, hopefully nothing is bent but most likely piston and valve at the minimum if we're lucky. Thanks.

 

[Nickster514]

Nick this is travis with the sidewinder from the lake I spoke with ur dad I will take a look at the sled fir him

Thanks Travis, hoping its not too bad.

 

[lakercr]

If it did skip when it was turned backwards, why didn't it immediately lock up?

Probably because the valve has finally broken off the stem, or another piece of metal has broken free.

 

[mooser17]

Wow never thought this would happen too these motors. I know on my 17 ltx le I turned backwards changing weights but will only move forward from now on. Sucks that this has happened!!!

 

[Turboflash]

Wow never thought this would happen too these motors. I know on my 17 ltx le I turned backwards changing weights but will only move forward from now on. Sucks that this has happened!!!

Yup, never turn these 998s backwards ever, even a little bit.

 

[74Nitro]

Just take the valve cover off and check the timing before yanking the engine to be sure.

 

[Turboflash]

Just take the valve cover off and check the timing before yanking the engine to be sure.

If engine is locked and won't turn over, then obviously something is in combustion chamber so head will have to come off as a minimum. Checking cam timing will confirm if it's off but still gonna have to remove head.

 

[74Nitro]

If engine is locked and won't turn over, then obviously something is in combustion chamber so head will have to come off as a minimum. Checking cam timing will confirm if it's off but still gonna have to remove head.

I was just wondering if possibly the PTO bearing has failed.