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Discussion Starter · #1 ·
Well i have an 04 800ho mxz that ive converted to a summit and on the 6th day of my trip to the mountains i fried a rod bearing! My sled has about 3400 mi on it.

I guess i was lucky because my rings, pistons, head, rods, and so on are all still ok, and it still has good compresion.

Has anyone else had a problem with there bearings in there sleds? One of my friends that was with fried his main bearing also.

thanks,
-Jesse
 

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Discussion Starter · #4 ·
BOON-DOG said:
more..... View attachment 47505
[snapback]711677[/snapback]​
WOW! that really sux. mine was the other cylender but not that bad for sure! What broke? (your rod obviously) but wat cuased it?

-Jesse
 

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Discussion Starter · #5 ·
Anyone have any input on what i should do to the motor while its gonna be torn down?

I was told i should run caged bearings? is that a good idea? true the crank? or should i just get a crank rebuild kit from ski-doo? If i had the cash id do the rkt piston/head kit for sure but $715 is just way more than i have right now.

thanks guys,
-Jesse
 

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millnoff said:
Well i have an 04 800ho mxz that ive converted to a summit and on the 6th day of my trip to the mountains i fried a rod bearing! My sled has about 3400 mi on it.

I guess i was lucky because my rings, pistons, head, rods, and so on are all still ok, and it still has good compresion.

Has anyone else had a problem with there bearings in there sleds? One of my friends that was with fried his main bearing also.

thanks,
-Jesse
[snapback]711522[/snapback]​
Rod bearing failures at 3400 miles are the direct result of 1 of 2 things??

1) Detonation hammering the big end bearing and eventually shattering the bearings and causing failure.. This is highly unlikely if you are running stock engine!

2) And MY personal favorite:: Lack of or lousy oil (or both)!!
People like to turn down the oil mix ratio because they think they will run stronger. When, in fact, nothing could be further from the truth... Less oil = less power and premature engine failure... The ideal ratio is 16:1 I run 24:1..especially with that idiotic oil injection system on the Series III engines (STUPID!!) Almost all big end failures (even rod breakage) can be traced back to lack of oil!! But that is another subject altogether!! Oh yea... ALL oils are NOT created equal!! There are majoe differences is how they do or do NOT protect!!

Kelsey
 

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Discussion Starter · #7 ·
RK Tek said:
millnoff said:
Well i have an 04 800ho mxz that ive converted to a summit and on the 6th day of my trip to the mountains i fried a rod bearing! My sled has about 3400 mi on it.

I guess i was lucky because my rings, pistons, head, rods, and so on are all still ok, and it still has good compresion.

Has anyone else had a problem with there bearings in there sleds? One of my friends that was with fried his main bearing also.

thanks,
-Jesse
[snapback]711522[/snapback]​
Rod bearing failures at 3400 miles are the direct result of 1 of 2 things??

1) Detonation hammering the big end bearing and eventually shattering the bearings and causing failure.. This is highly unlikely if you are running stock engine!

2) And MY personal favorite:: Lack of or lousy oil (or both)!!
People like to turn down the oil mix ratio because they think they will run stronger. When, in fact, nothing could be further from the truth... Less oil = less power and premature engine failure... The ideal ratio is 16:1 I run 24:1..especially with that idiotic oil injection system on the Series III engines (STUPID!!) Almost all big end failures (even rod breakage) can be traced back to lack of oil!! But that is another subject altogether!! Oh yea... ALL oils are NOT created equal!! There are majoe differences is how they do or do NOT protect!!

Kelsey
[snapback]711815[/snapback]​
Well i dont think i had any detination, plugs and head look good and i was jetted fat so that pretty much rules that out. Oh and the only "performance" parts on my sled are slp can and hot air elemintion vents, and a holtzman atacc. It never over heated, or ran out of oil (i have an oil caddy so i always filled her up when i got gas)

What does detination sound like by the way?

As far as oil goes i sure hope i was using enuf. im going threw at least a quart per tank of gas. i havent adjusted my stock pump so ya. And as far as using crapy oil i dont do that eather. After the 1st tank the sled has had amsoil intercepter run in it.

Im NOT saying your wronge! just i dont understand what cuased it? maby got a bad batch of oil or something? eather way it sux.

Thanks for the info,
-Jesse
 

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Millnoff detination, or pre-ignition will sound like a pinging noise. If it is bad enough you can hear it on the right hand side of your sled. On the 800 doo you can sometimes hear it when your are letting off the throtle after a hard run, worst case scenario for detination is wide open throttle then slowly backing of to 1/2 or 3/4 throttle, not may 2 strokes will take it unless they are set up very rich on fuel delivery.
I to am wondering why all the rod failurs. Kelseys theory sounds good, i do not like the doo oiling system ether. Iam getting nervous, 5600 km no rod failurs yet. Hoping my additional oil mix and being careful with the throttle is my saviour.
 

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Pardon me i meant left hand side.
 

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Well i didnt notice any weird noises wile i was riding. If you have detination is there any way to tell other than the noise? I dont think that was the problem. i was running 340 mains and 20 pilots, (that was for 6000') and the fuel screw out 1 more turn than stock. 99% of my riding was at 8000'+ so i should have been plenty rich. plugs were a dark brown. Like i said b4 the head rings and cylinder walls all looked fine?
Ive always ran amsoil in every car, sled, and seedoo i own and have never had a problem. Everyone i know up here runs it, maby it was just time for it to go.

I dont understand what happend? eather way i guess i have to fix it !

thanks again everyone!

-Jesse
 

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Discussion Starter · #11 ·
Well i just talked to my deal and he said hes had to order 2 other cranks due to bearing failures in the last 6 days!
*%@ is up with skidoos bearings in there 800s? just thought id let people know that.

-Jesse
 

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millnoff said:
Well i have an 04 800ho mxz that ive converted to a summit and on the 6th day of my trip to the mountains i fried a rod bearing! My sled has about 3400 mi on it.

I guess i was lucky because my rings, pistons, head, rods, and so on are all still ok, and it still has good compresion.

Has anyone else had a problem with there bearings in there sleds? One of my friends that was with fried his main bearing also.

thanks,
-Jesse
[snapback]711522[/snapback]​
My dealer advised me to have the top end done at 1500 mi and crank at 2500 mi on my 04 Summit 800 for full throttle operation in the mountains of Sicamous
and Revy. Would be nice to have TTabs workshop while ripping her apart, instead of under the deck.
 
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