Some here have been posting threads on oil leaks, so here is a writeup/ pictoral of a recent job I just did.

The bike is my buddies 03' RKC with 65K on it and it is so stock, it's original. He had an oil leak coming from behind the primary, so I took it apart to see which seal was leaking. Notice I said which seal. There are 3 seals on the inner primary and 4 seals of possible leaking on the tranny (all replaced). Here they are and notice I included what brand we bought:

Inner Primary:
1. Jackshaft seal, Cometic
2. O ring (crankcase to primary), Cometic
3. Lip seal ( primary mainshaft), Cometic
4. Mainshaft bearing, HD
5. Mainshaft bearing inner race (stays on main shaft) HD

Trans:
1. Shifter shaft seal, Cometic
2. Quad seal (mainshaft), HD
3. Mainshaft oil seal, HD
4. 5th gear seal, HD

Tools which you will absolutely need:
1. Service manual
2. Main drive gear large oil seal installer ( I used and HD one).
3. Custom made 1 7/8" long mainshaft deep socket.
4. 3/4" impact with a supply of 135 PSI line pressure.
5. 1/2" & 3/4" Torque wrench.
6. Custom made sprocket locking tool.


Because you don't know which one is leaking until you take off the inner primary all become suspect ( good reason to use red colored tranny oil).
I will have to use 2 posts to show all the pics by number.

21. Sprocket locking tool
22. Sprocket locking tool wedged between to 2 sprockets locking them together.
5. Mainshaft seal (looking from back side of inner primary.
6. Jackshaft seal, (shaft carrying starter gear).
2. shifter shaft seal, can be pulled out by drilling a 1/16" hole and putting sheet metal screw in and pulling out.

 

The next set of pics show the other seals.

10. Mainshaft tranny seal.
11. 5th gear seal (remember you have a mainshaft within another shaft).
12. Quad seal.
17. Custom made 1 7/8" socket with 3/4" impact being used on counter sprocket and believe me you will need it.
13. Main drive gear large oil seal installer being used to lightly yap in seal.

Guess I need one more post to show some other pics.

 

more pics:
13. Main drive gear large oil seal installer being lightly tapped in.
14. 5th gear oil seal being lightly tapped in with 1" pipe.
7. Might as well replace that primary chain guide.
19. PAY ATTENTION: Those 5 bolt holes that sit in the oil bath require Silicone RTV sealer around the holes on the seal surface and in the bolt holes, don't scimp.
3. You will need some basic and specialty tools to do this job, get them.

The important take aways from this job are to take your time and use the appropriate tool for the job. The inner race for the main shaft on the inner primary would not come off without using a tool grinder to cut it off (not un common), don't get into the mainshaft. Can't emphasize how important the RTV sealer is for the bolts within the oil bath or you can expect some leaks after. The 5th gear seal will require you to dig this seal out, again don't get into the shaft. The counter sprocket nut will have to come off to get to those tranny seals and you better have a BIG breaker bar or the 3/4" impact as this nut gets red Locktite. If you have to take off the inner primary it's best to replace your mainshaft bearing and all tranny seals while it is off.

So, now you can see when someone says they have a leak, it could be from multiple sources. And like I said earlier, it helps to pinpoint oil leaks if the tranny oil has a different color.

 

Thank you for posting, very informative.

 

Great Post!!..........thanks!

 

Great post. Very helpful

 

Thanks for taking the time to document what was done. I’ve got a few questions.
Did you replace both races and the main shaft bearing since you had to cut the inner race out?
What did you have to modify on the 1 7/8” socket?
What tool did you use to get the counter sprocket off? The impact gun or a huge breaker bar?
Did you find out which seal it was that was leaking?

Again, thanks for the writeup.

Carl

 

3/4 impact holy sh**, didn't think anything on a Harley would require that much force, hell we use em here at the CAT dealership I work at, and 1 inch of course.

 

Thanks for diy pics and info

 

Great post, thanks.