If the oil is gear oil, it is tranny fluid. If it is black engine oil, it is from the primary. Shovels circulate engine oil through the primary unless the oiling system has been modified.
The problem is most likely a transmission seal.

 

There are two seals in the left side of a Shovelhead transmission. One is around the mainshaft gear and s a large seal. The other is inside the maiinshaft gear between the drive shaft and the inside of the countershaft gear. Leaks are common on Shovelhead transmisions at these points and are often difficult to stop.

There is also a spacer around the countershaft that the large seal rides on. Those can get grooves in them and cause most of the leak.

You can remove the transmission while leaving the inner primary cover in place but it makes little sense to do so. The transmission can be worked on for replacing seals while still in place with the primary off. No need to take it out unless you need to work on the gears and bearings.

 

The story is that the transmission was removed and rebuilt. If this was true, it wouldn't be leaking just because the primary was left in place would it? I guess I'm wondering if the tranny was really rebuilt, the seller has no reciepts for tranny work.

 

Maybe this will help... http://www.v-twinforum.com/forums/showthread.php?t=54592

 

Thanks, very informative. I am right in thinking any tranny fluid leaking is a problem with the transmission itself and not a tranny to primary seal as I have been told.

 

Many times the old 4speeds will leak not actually related to the main seal.
What happens is the the soft lock tab under the sprocket left hand threaded retaining nut crushes and thus losing tension, this alows oil to creep out.
On the the very last HD 4speeds the soft lock tab was omitted and they used a short cap head screw in the sprocket itself to jam the corner of the nut to retain it and solved the problem.
Most dont know that and will use the lock tabs upon rebuilds.
It takes alittle time to drill and tap the drive sprocket, the results are worth it.

 

I've been looking at various old shovels lately and the latest one apparently had the tranny rebuilt but because they removed the tranny without taking off the primary? it leaks tranny fluid now. The owner tells me that I could remove the primary and replace a seal to fix it. I don't know much about shovels but if the tranny is leaking isn't that a problem with the tranny itself? is there really a seal between the tranny and primary that could cause a fluid leak? An oil leak from the primary seems more feasable not tranny fluid or am I way off.

How bad does it leak? If it's just a drip here and there then i wouldn't let that one thing deter you from buying the bike. Very rare to find one of these old bikes that don't leak a little. If you do find one then jump on it, because it's been owned by a master mechanic that's spent a lot of time on it.

 

I get the impression that it's more than just a drip. This won't deter me but it will make a difference on any offer I might make since the story about the tranny rebuild and leaking from the primary don't seem to be true.

 

the mainshaft seal is tough to get tightened down properly without a special tool or homemade socket, its a very thin nut , maybe it is not tightened down enough or maybe just overfilled.

 

Most folks think that if they get a nice, clean install of a new seal, it won't leak. However, since these seals are usually staked in, there's often a small burr on the tranny case. When you pull you old seal out, closely inspect the outside rim of the seal, where it contacts the case. If you see a small straight line down the edge, the seal was damaged on the way in, but looks good once it's installed.
I've addressed this by not only cleaning up old burrs, but also, I apply a thin layer of that orange gasket maker to the OUTSIDE rim of the seal while installing.

 

Getting ready to tear into the main shaft of my wifes shovelhead again. I don't mind a few drips, but on a hot day it pours out after a long ride. Got all the info on what to do, just have to get stared. Big job for me!

 

When you do it, don't focus only on the seals. Many Shovelhead transmission leaks at the countershaft are caused by worn main bearings, bad spacers and the like.

 

Thanx for the tip newultra! I'm sure stuff is worn in there from all these year of riding from the two previous owners and us. May be time to pull the whole tranny and put in on a bench for some rebuilding.

 

Transmission shaft leak Harley

Just a little indication. Stick your finger on the leak and smell it. Tranny oil stinks really aggressive, where as primary oil (10-40 on concealed primaries - or 20-50 or 50 on primaries with a constant flow from engine) smells rather neutral. You can sniff your oil tank quite easily just to make sure.
Good luck, ride hard.
Curt

 

In 13 yrs, I think he figured it out.

Sent from here to there.