Harley Davidson Engine Protection Tips

Harley Davidson Engine Protection TipsBack in the good ol’ days, when men were men, and gun slingers roamed the West, nobody knew or cared what an oil slinger was. Besides, oil wasn’t needed so much as buffalo grease. But if you ride a Hawg you better know what an oil slinger is and use one – or you might find yourself stranded by the side of the road with a frozen clutch pushrod or disintegrated thrust bearing!

Especially when you are running an open belt primary, you need to keep oil flowing over all the internal surfaces of your tranny. An oil slinger does that quite well. What it is a metal disc with castellation?s around the edge (notches) that picks up oil from low down, under the mainshaft and clutch pushrod in the right-side housing. It slings that oil all over the innards of the cover, so it gets onto the thrust bearing and the pushrod. Although the manual says you should fill the tranny to just under the filler opening, if you run an open primary you know that the fluid will end up leaching out of the end of the mainshaft. You can’t keep the tranny fluid level high enough to keep that pushrod covered, so the oil slinger can save you trouble and money.

J&P Cycles sells a kit that includes the thrust bearing, oil slinger, pushrod and fork. The oil slinger slides onto the pushrod just behind the thrust bearing washer and locks into a couple of flats on the rod. For just under thirty bucks you can buy some peace of mind.

Transmission Mainshaft Oil Seal

One day you arrive home after a brisk ride on your chopper. You notice that black gook is all over your rear wheel rim and on your chain guard! A puddle of oil is forming under your clutch basket. “What the fuck?” you say.

Oil puking out of your tranny is a sure sign that your mainshaft oil seal isn’t doing its job and needs to be replaced. You need to remove the clutch basket and countershaft drive sprocket to expose the seal. Pry it out with a screwdriver, and replace it with a new seal.

The oil seal is made of a flexible plastic like neoprene. It has a tension spring surrounding the pressure-fit hole, and a cavity surrounding the spring. Install the seal with the spring and cavity facing the transmission body. When installed, you will see the flat side of the seal facing you.

The seal needs to be seated firmly by setting it carefully using a hammer and dull screwdriver or flat-ended punch. The oil seal must be seated flush with the bearing behind it, so it is pressure-fit against the bearing. It should be seated to refusal, evenly, but not pounded back so hard as to break the plastic or dislodge the bearing. A sharp tool can break through the plastic, so be careful!

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  1. Rob Fleming - August 31, 2011

    New blog post: Harley Davidson Engine Protection Tips http://t.co/2HNJO2K

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