Main tranny seal

Transmission, clutch, chains and belts
Forum rules
Please do not start new topics here, but here: New Panhead and Flathead topics
Post Reply
Posts: 15
Joined: Fri Jul 13, 2007 9:30 am

Main tranny seal


Post by kaptekarev » Mon Mar 05, 2007 1:44 pm

Description: My 61 Pan is hemorrhaging oil, from the main tranny seal. Does anyone know what size that thing is?

Post by kaptekarev on Dec 12, 2006, 3:18am

My 61 Pan is hemorrhaging oil, from the main tranny seal. I've gotten all the way to the humongous nut that retains the main sprocket. Does anyone know what size that thing is? And what depth (brand) of socket do I need to get it off?
Also, where do I get one of those seal puller tools?

Post by caschnd1 on Dec 12, 2006, 5:39am

The sprocket nut is 1 7/8" (left hand threaded). I don't know where you can get a socket to fit it. I've seen people take a standard 1 7/8" socket, cut it in half and weld a 7" piece of pipe in the middle. I personally use a very large 1 7/8" wrench to remove and install the nut. It's works just fine with the transmission still mounted in the frame.
You can get a tool for removing/installing the main seal from JIMS. I've got one and it works great. I don't think the special tool is a requirement, but it makes the job easy and makes sure you get the seal set 0.050" below the edge of the trans case.


Post by jellero on Dec 13, 2006, 5:39am

napa has seal pullers, $11. j

Post by fourthgear on Dec 13, 2006, 4:08pm

Hate to sound like a barn yard mechanic ( to some) but to remove that seal all you need is two self taping screws of the appropriate size and just pull it out with pliers.
Look up past threads on what to replace seals and nut with , there are better than stock replacements out there and no seal will last very long trying to work with worn out bearings ,shafts, etc..

Post by kell on Dec 21, 2006, 2:24am
ourthgear wrote:
no seal will last very long trying to work with worn out bearings ,shafts, etc..
don't forget "bushing"

Post by fourthgear on Dec 21, 2006, 1:41pm

Yep , that one too!
I once got a 69 to restore that was in storage for about eight years and after changing fluids , points plugs and checking the timing etc., I started her up on the kick stand and was in the process of adj. the idle and away she started to go, lucky for me I got her shut down before she hit the shop wall . Come to find out the main shaft bushing locked up in the main drive gear and when we tried to disassemble the main shaft we pulled the bushing out of the gear and ended up having to cut through the gear to cut the bushing to get it to release from the main shaft to get it apart. I guess we spent about forty bucks on cut off wheels to cut thru it . conclusion is we think because it had Andrews gears in it , that bushing we think was not set up right , maybe not line honed or some thing to that effect, just a little too tight and the length of storage might have had some thing to do with it too.

Post by kell on Dec 24, 2006, 10:18pm

I mentioned bushing because I had a bad leak from a worn fourth gear bushing. All the rubber seals in the world won't fix that.
But first just replace the main seal, you can do it without taking the transmission out of the bike. See if that fixes it.

Post Reply

Return to “Transmission, Clutch, Belt & Chains”