my 77 flh is leaking trans fluid and it looks like it's leaking behind the inner primary cover .If that is where it's leaking can it be fixed on the bike if i take the inner primary cover off .I'm thinking it's a seal thats leaking .If this helps when the bike is on its kickstand and leaning to one side it leaks .Now that it is on the lift and straight there is no leak so i am assuming that the seal is leaking .thanks i can sure use some advise .

 

Yep sounds like the main seal. You need some specialized tools to remove the inner cover. You have to remove the front sprocket, chain adjuster, clutch and clutch hub. Then the starter housing from the back of the inner primary. Look in the factory service manual under striping the motorcycle for transmission repairs. It has all the steps you need to reach the transmission. You will encounter two left hand nuts, one on the clutch hub and the other that holds the transmission sprocket.

If you plan to keep the motorcycle, buy the manuals, service and parts. Also buy a clutch hub puller for a 4 speed transmission. The other specialized tools are nice but sometimes you can get by without. I would get the one for the counter shaft sprocket nut also. It makes life much easier. I use a slide hammer dent puller, that has a sheet metal screw on the end to pull out the old seal. You can use a large piece of pvc pipe to tap the new seal in place.

If you have never done this make sure you read and re-read the manual and look at the parts breakdown in the parts manual before you begin. Get your repair parts, seals, gaskets, new lock tabs and safety wire before you begin. Chances are you will need to replace your sprockets while you have it apart.

 

Hey filthy,does his bike have a "SUPER NUT" for the sprocket?
I heard this was a factory flaw with just a nut without the seal in it.
If so he can upgrade the nut.

 

Would like to add,check good where the oil is actually coming from, meaning, which side of the gear is very important, that being said, still replace them all.

 

Usually if it is leaking, the seal is not the real problem...it is the bushing in the main drive gear is worn out... and if you don't replace it, it will leak again in short order.

http://www.caimag.com/wordpress/2010...real-solution/

 

Great link, seen something similar on utube, 45° bevel on spacer to except a viton o ring which looks a little easier but still great fix.

 

Link?

 

When you get into it, there is a itty bitty "L" key that locks the inner spacer to the mineshaft. It can easily be missed due to grease and gunk built up behind the sprocket. If this key is not put back in, it will cause premature wear on the mainshaft seal. A lot of people miss this and it very well may be missing from a previous owner. It is only on the ratchet tops and not on rotary tops. This, along with a main shaft bushing and seal will generally clear up any tranny leaks you may have.
As mentioned before, a factory shop manual and proper tools, along with taking your time, will get it done right.

 

Yeah, tom84 post has a link there, just click on that .

 

Yep, issue from the factory. Supernut helps, but the true fix is to put a mainshaft spacer in that has an o-ring on it. Google "Saddlebagrail" and you'll see a guy in Canada that makes em. I've bought a few already for the old Shovel trannys I rebuild and have never had one leak again (unless you tear the o-ring seal during the install. I think that's why Ray (Saddlebagrail) ships two o-rings with each spacer. I think it was $40 plus the ride the last time I bought one from him. There was even a YouTube video or three with Ray showing his fix for the issue.

Some guys have had luck with a Supernut and/or some silicon around the outside of the mainshaft seal. A band-aid to the problem but, hey, whatever the bike owner wants.

Best of luck!

Hobo