How does the front counterbalance shaft bearing get oil?

[Pwnage1337]

As the title states, how does it get oil?

Is there a passage in the crankcase that feeds oil to the bearing? It seems unlikely that the fuel/oil mix makes it's way all the way through the case to that bearing.

I had a failure on that bearing and want to find out why it failed.

 

[JeremyD615]

The counterbalance shaft gets a small amount of oil during assembly, but the only lubrication after that is whatever two stroke oil can make it’s way in there from the crankcase. I had a front bearing failure late last year as well, and wondered the same thing. Unfortunately there’s really no good way to be sure it’s getting lubricated once the motor is assembled and installed.

 

[Pwnage1337]

Sounds like a candid for case modification just like the early 800 skidoo motors.

I'd be surprised if someone hasn't drilled a passage for it on some high dollar motors

 

[DanSquires]

that bearing is a sealed unit, and in my experience the only way it ever fails is if the shaft seals wear out and there is water intrusion.

 

[Pwnage1337]

That's good to know. Bearing must be packed with some good grease from the factory then.

 

[JeremyD615]

That's good to know. Bearing must be packed with some good grease from the factory then.

It’s not packed with grease, there is some 30wt oil that is poured in during assembly.

 

[Pwnage1337]

My understanding was that the oil that is poured in there is only for the lubrication of the meshed gears of the counterbalance shaft and crankshaft, not necessarily the bearing at the front of the motor (MAG) Piston

Isn't it only like 1 oz that goes in there? Would 1 oz of oil splash around enough to get up to the bearing at the MAG side of the engine?

Just seems like a tiny amount of oil to me to be lubricating the bearing, and the meshed gears of the crank and counterbalance shaft.

This is a rather confusing subject, if you search along the internet people say the CB oil you add during assembly is burned by the PTO cylinder during operation, and is eventually replaced by the injection oil. But when I split the case on my engine that grenaded, the oil that was in the CB cavity was dark grey, like used motor oil and it had the consistency of motor oil.