1987 EVO Motor Question
This only began happening the last couple of years when I infrequently rode it. A couple of shops I talked to ( non HD) indicated this was normal! I don't think so.
What are your experiences??
Thanks
cleaning it just ain't enuff..
Your seat needs lapped or burnished to get that positive seal.
Lapping it requires using a check ball & braze it to a long rod, add a bit of valve lapping compound (not much) cause ya don't want ANY to get in the pump !!! & rotate it like 1/2 turns back & forth.. Keep doing this till you see a clean even seating surface all around..Clean out thoroughly add new check ball & new spring & reassemble..
There is also a seat cutter, for bad seats..
I would suggest also: take yer breather hose outta yer air box & aim it under the bike & add a tiny filter breather.. Leave it under there...
Plug the hole in the backing plate..
Last edited by Buddy7394; Nov 7, 2008 at 12:15 AM.
This topic should be a FAQ somewhere. It comes up all the time. Even a friend of mine in my British car club asked me about it on his 74 Shovelhead.
The oil pump shaft seal is more often the culprit on the pump, but the most common things are:
Excessive blow-by which forces an abnormal amount of oil vapor into the breather hose itself. Keeps the vapor on the scavange side "whirled" up on everything, not allowing it to settle to the sump gears when running. Then after sitting a long while, it settles and the pump cannot pick up the liquid fast enough, then the blow-by pushes the extra out the vent on start-up.
Then there's the breather gear itself. They are plastic and will wear out. Also they can easily break teeth, but I've yet to see one get out of time because of a broken tooth. Most people will advise a metal breather gear, but I have very mixed feelings about that.
So yes, it's "normal" to a degree but I think 2 weeks should not make that big of a mess. Check your compression (by the book) and if it's 145 or less, suspect worn rings/pistons. If the compression is good, maybe check the breather gear in the nose cone.
But no matter what, by ALL MEANS, disconnect the pipe from the air cleaner and route it in a loop (higher than the block fitting) then down under the bike - slip on filter optional. Even a new engine of that era will let out a drop or 5 after sitting a few days on start-up and usually a drop or 2 after running is normal. Most dealers did what I (and others) just mentioned on the 1st warranty checkup.
And if you don't like any of the suggestions, just ride it a lot more often - life will be better if you do
This only began happening the last couple of years when I infrequently rode it. A couple of shops I talked to ( non HD) indicated this was normal! I don't think so.
What are your experiences??
Thanks
Thanks Again
Trending Topics
http://www.bigboyzcycles.com/showthread.php?t=87
The Best of Harley-Davidson for Lifelong Riders
http://www.bigboyzcycles.com/showthread.php?t=87
Something else that won't "fix" the problem, but will prevent it from happening, is to install a straight-through quarter-turn plug valve in the line between the oil tank and the oil pump. The plug valve will not impede the flow. BUT(!!!!!), ya better remember to open the valve before you start the engine!
Last edited by pococj; Nov 15, 2008 at 10:14 AM. Reason: Added plug valve "fix"








