Help Please with Tranny Shaft

[rigormortis]

I have a Yanmar 4 banger with a Kanzaki-Hurth KBW20 transmission and I need to replace the output shaft oil seal. Confounded by retaining nut. I have the special tool required to undo it but two things:
1.which way do I turn the nut to loosen it? According to service manual the output shaft rotation in forward is 'clockwise as viewed from stern'.
2. There appears to be a locking ring on the end of the shaft. Is this part of the nut (as in a collar) or is it simply a friction fit ring that has been dimpled into the notch. Please see attached photos.
Any help appreciated. I suppose my next posting will be 'how to get the coupling flange off the splined shaft' but that is for another day.
Thanks in advance.

[boden36]

Hi, the collar is part of the nut. Just drive something in under the indented portion to bend it out of the slot.
You may want to use a chain wrench around the flange to hold it whilst undoing the nut or make up a bit of flat bar with some boltholes so you can bolt it to the flange for holding purposes.
Regards,
Richard.

[rigormortis]

Richard:
Thanks for the info. Which way will the nut loosen, then? In forward the shaft rotates clockwise when viewed from the stern.

[perchance]

It could be a left hand thread. Can you see any of the thread to verify?
To get the coupling off you may need a puller and some heat.

[nv5l]

It's a regular right hand thread.

[latogato]

This is my first post on this site, so I'm not certain if this is the correct place to do it...
I also have a leaking output shaft seal and I am in the San Blas Islands of Panama. I need to pre-order the oil seal from the seal and bearing shop in Panama City but I cannot find the seal number anywhere online.

Can anyone help?

Johh
S/V Katemba
Island Packet IP38-22

[sy_gilana]

Hey John...howzit
For a moment there on the thread title I thought I was in the wrong forum!

[sy_gilana]

John, Most seals carry a number made up in Millimeters. For instance a 16327 is a 16mm shaft, 27mm OD and 7mm thick.
I suggest you measure the shaft and the OD with a vernier, then go to the online shop Simply Bearings Ltd ~ Oil Seals SKF FAG TIMKEN KOYO NTN NKE TRULOC Needle Rollers Taper Rollers Rod Ends Oil Filled Bushes Loose Balls O Rings Grease Plain Thrust
To identify the seal from their massive database. The only thing that can be "wrong" is that you might have a double lip seal or single etc. BUT you could spot this by looking at it carefully. Also, try to see if there is any number imprinted on the visible side of the seal, and use it as a cross reference. Good luck
M.

[latogato]

Thanks Mike
The problem is that I do not have the seal in my hands to measure. The entire transmission is still intact and in service. I am trying to get the seal so that I have it available when I tackle this project at Shelter Bay Marina.

It is a Yanmar 4JHE with KBW20 transmission. I have Googled "KBW20 parts catalogue" but it seems they have every part number in there except the output shaft seal that I need!!

I was going to call you on the net in the morning for help on this btw. Also the notifications from this forum are going to the correct email address. I guess I was too busy working to devout any time to the responses. (Thanks anyway,All)