crankcase oil seal replacement

[93evorider]

I have a 93 heritage- i was doing my spring tune up and was draining the primary only to discover about 3 qts of engine oil in there(bikes been siting idle since oct). Thinking its the oil seal  in the crankcase. anybody ever replaced one of these? Looks straight forward but that can be decieving sometimes- pull the clutch and compensator ,then the rotor and there is the seal--any ideas would be helpfull  -- Thanks 93evorider

[chadlyp]

first off, if this happened when it was sitting since October, you have another issue... the dry sump motor should not fill up with 3 quarts of engine oil ever, and certainly not when it's sitting, so it should not have been there to leak into the primary in the first place... but since it has, you are experiencing an issue with the oil feed check ball which is used to keep the oil in the tank until the motor needs it... a lot of older bikes will experience a little leakage and just blow it out of the breather upon first start after a long sit, but 3 quarts is pretty excessive... most likely need to refinish the seat and replace the ball and spring while you're at it... that said, the seal should be oriented so that the lip is towards the "wet side"... on a wet primary setup like yours, this means that the lip should face the primary (or away from the motor), remember that the dry sump motor isn't supposed to fill with oil, so the motor side is considered the "dry side"... usually when changing to a dry clutch/belt drive primary we reverse this and orient the seal lip towards the motor... the newest seals from HD are a new double lip seal and should be oriented per the markings...  other than that, just lube the ID and OD of the seal with clean motor oil and be sure it goes in straight and evenly all the way around and don't damage or bend the edges (especially the thin lip edge)... i usually kind of get it started by hand and carefully and slowly work around in a circle the entire diameter of the seal several times with a dead blow hammer until it's all the way in... also check first that the bore in the case and the spacer on the ID are clean, smooth and free of scratches or burs

[93evorider]

thanks chadlyp
      Knew oil wasnt suppossed to leak in to the crankcase while sitting-it hasnt done this before so how do you refinish the check ball seat with out pulling the pump?

[chadlyp]

people say a lot of different things, but it's my contention that every one of them will introduce some kind of shavings, compound or scotch-bright fibers into the oil passages... my answer is to remove the oil pump... it's honestly not a very big job and only costs the price of a few gaskets... there is a tool designed for cutting a new seat and it is what i use, i've also heard of lapping compound on the end of everything from an old pushrod to an old checkball glued to the body of a hollowed bic pen... if you where gonna do it with lapping compound, i recommend in series course, medium and then fine grit somehow applying it to an actuall checkbell (not the one you're gonna install in the bike) and putting it down in the clean hole and rotating it clockwise-countercw-clockwise-countercw intil it cleans up... the "glued to a hollowed bic pen" thing isn't actually that bad an idea... the reason i suggest an actual checkball is because it is the only thing that we know for sure is the right size/diameter... any ways you do it, the oil pump should come off because you have to get all the shavings and/or lapping compound out

[chadlyp]

oh, and the bonus is that you then have all new gaskets and seals for the bottom end! and you get to inspect the oil pump for wear/damage!

[93evorider]

thanks for the info chadlyp
          looks like i have a little work for the weekend

[Norton Commando]

If your oil pump is leaking past the little ball-check, here's what you can for cheap and easy fixs. First buy two new ball checks.  Then remove and discard the ball-check from your pump and install one of the new balls in its place. Next, lightly but firmly tap the new ball into the seat of the pump using a hammer and a suitable rod.  I use a wooden dowel and a small ball-peen hammer.  Next remove the ball that you just pounded against the pump seat and install a the second new ball that you purchased.  Reinstall the spring and threaded cap and your done!