Drive side crank seal

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Nov 18, 2005
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What size is the crank journal on the drive side?
The oil seal I took out says 1.125" but the book says the bearing inside diameter is 30mm. Presumably they run on the same part of the crankshaft.
The reason I have a problem with it is that there is some slight damage to the crank where the oils seal runs, and I get a slight weep from the seal so i want to put a redi-sleeve in there.
I bought one for a 1.125" shaft but it won't fit on.
The shaft is 30mm ID and a seal at 1.125" looks a little tight, though I've never looked at the numbers on any I've fitted.
I don't think you will get a 1.125" redi-sleeve on to a 30mm shaft, even with a big hammer.

Are you running a dry belt? if so, and the leak persists it'll be coming through the stator mounting studs. A little loctite will fix that.

I'm running a single row primary chain without a chain case. So it's definately coming from the oil seal.
I'll have to try a 30mm redi seal I guess.
crank seal sleeve

Did the 30 mm sleeve work and stop the leak ? I have had 3 new seals in my 850 and cannot stop the engine oil getting into the chain case, crank does not look marked or worn .
No the 30mm sleeve didn't fix it.
Essentially, the sleeve makes the diameter that tiny bit bigger and it has a little step for the seal lip to get over, and it damaged the seal inner lip when I fitted it.
I checked all the dimensions and the seal is inch and an eighth ID. That's 28.14 mm. It's already asking a lot of the seal to fit over a shaft that is nearly 2mm larger than it's designed for.
The guy in the bearing shop was suprised the seal worked at all on that sized shaft.
Next time I pull the engine down, I'll get that surface machined down a bit to take off the vice marks that are causing the problem, and it will be nearer the design limits of the seal.
I haven't got a seal handy to check your dimentions, but are you sure you are getting the correct seal? seems darn tight to me.
I've used seal saver sleeves a few times, they all were shaped at one end to allow the seal to slip over, perhaps not all.
Have you tried stretching insulation tape round the step working outwards over the shaft, then apply some grease. It should then slip over nicely without damage.
I'll try and find out the seal spec this week.

Best of luck,

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