oil leak from transmission sprocket

perkinja

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I just rebuilt this engine and I'm getting oil leaking at the chain sprocket from the transmission. I took the sprocket off and started it up to see if it was my seal and its not. The oil is coming from where the sprocket slides on not the transmission. Did I mess something up putting this back together or is this totally normal? I attached a picture to better clarify for you guys, its where the sprocket slides onthat its coming from.
 

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Did you torque the sprocket nut down to spec?

Without looking it up, I think it's something like 65 ft lbs.

If you don't get it tight, it WILL leak.
 
The nut cut out fits over the end of the splines. It needs to do this so the sprocket pushes on the spacer that goes through the seal.
As the engine runs, oil gets pumped between the seal and bearing, through the bearing for lubrication and cooling.
The spacer rides on the shaft bearing inner race, the sprocket pushes on the spacer. The proper torque pushes these parts together hard enough so oil won't seep in between the bearing race and spacer, then out between the spacer and sprocket.
This oil leak is often found. Often the nut is on barely finger tight.
Leo
 
I flipped the nut around and torqued it down to spec. There was a lot of oil on the chain that was getting sloshed around so I'll check it every day and if its still leaking I'll post back.
 
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