The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Rob Valdez 79 R65 on June 18, 2008, 01:49:13 AM

Title: Leaky final drive - Still Leaking
Post by: Rob Valdez 79 R65 on June 18, 2008, 01:49:13 AM
Look at what followed me home from the Gathering...

(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F98862543%2Fmedium.jpg&hash=724a827b0a580bf9b98ed504daaa35f90d054aa4) (http://www.pbase.com/tomfarr/final_drive)


I have never repaired a final drive before.  Any advice?
Title: Re: Leaky final drive
Post by: billygoat on June 18, 2008, 02:56:00 AM
 Could need a new crush washer. You need to find out there the leak is coming from. It could be one of the drain bolts.
Title: Re: Leaky final drive
Post by: Semper Gumby on June 18, 2008, 08:28:41 AM
High Rob.  Two things:

Where is that leak????  It looks like oil is coming out the axel????

Also:

There is a small weep hole just inside of the bottom drain plug.  MAKE SURE this is not clogged otherwise your rear brake shoes will be contaminated with gear lube (bad).

Clean the external surface of the final drive and watch for new oil.

Pull the wheel off and look inside.  You should see oil coming from below the spline on the final drive into the bottom of the rear brake area.  I have a feeling that the bottom weep hole is pluged and the rear wheel is slinging gearlube around.  BTW_ I have this problem as well on my 1980 but the weep hole is open and there is just a bit of wetness around the drain plug - rear brakes still good.

BTW - For you drivers of the squared off rear end (Sept 1980 and on), your bikes don't have the weep hole.  Caveat Emptor.

Good luck Rob - I'm just deciding when to take the rear drive to Nathan at Boxerworks.
Title: Re: Leaky final drive
Post by: donbmw on June 18, 2008, 09:21:15 AM
As others have said. Washer on drain plugs, loose drain plugs did you change oil sometimes back. How old is the final drive seal. Not sure on you final drive but the brake shaft may have orings on it. The final drive seal is no big job to change. Just change my on the 82 for the first time.  

Don
Title: Re: Leaky final drive
Post by: Rob Valdez 79 R65 on June 19, 2008, 02:51:53 AM
I removed the wheel tonight to examine the other side.  

Here are pictures:
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F98904506%2Fsmall.jpg&hash=ef789a2c9980e85071cf8e076fe7119dae29571d) (http://www.pbase.com/tomfarr/final_drive)

It looks really dry in there.

I also discovered, while ordering parts, that the early, round-case final drives did not have o-rings on the brake actuator shaft!  

I have heard of the shafts with two o-rings being modified to take 3 (or something like that).  I wonder if the earlier shafts can have grooves machined into them, and work?

BTW, I have almost 87,000 miles on the bike.  The final drive was taken apart when I had the drive splines renewed back in 1998 at around 60,000 miles.

It's just old...
Title: Re: Leaky final drive
Post by: trolle on June 19, 2008, 03:17:04 AM
Quote

It's just old...

Find a nice oil field for her to pass her last days in leasure  [smiley=1drink.gif]

greetings from a precipitating norlth

trolle
Title: Re: Leaky final drive - First Ride
Post by: Rob Valdez 79 R65 on June 27, 2008, 04:28:30 AM
I finally took her out for a ride tonight after work.  It is nice and peaceful at 4 in the morning!

All I have done is clean everything up, change the oil in the final drive and the drive shaft housing, and blow compressed air through the two vent holes.

I rode it around the neighborhood for a few miles, and checked it, and no leaks.  So I jumped on the belt-way and headed up to the first exit, for a loop of about 10 miles at 60-65 mph.  

No leaks when I got home!

Tomorrow should tell.


Does anyone know of a source for 12 and 14mm copper crush washers???
Title: Re: Leaky final drive - First Ride
Post by: montmil on June 27, 2008, 08:43:16 AM
Quote
...Does anyone know of a source for 12 and 14mm copper crush washers???

Lemme check some of my VW Cabriolet bits. Volkswagen loves copper washers. Be back later...

Monte
Title: Re: Leaky final drive - First Ride
Post by: montmil on June 27, 2008, 11:10:25 AM
Quote
Quote
...Does anyone know of a source for 12 and 14mm copper crush washers???

Lemme check some of my VW Cabriolet bits. Volkswagen loves copper washers. Be back later...

Monte

I'm b-a-c-k...  Here's a link to my favorite import car parts supplier, AutohausAZ.com. The link will take you to a page where you can shop metric copper washers to your heart's content.

https://www.autohausaz.com/search/product.aspx?sid=rfdbo3mohi0tfunzgcamn155&makeid=800026@VW&modelid=1280348@CABRIOLET%20%20&year=1986&cid=99@Tools%20%26%20Shop%20Supplies&gid=1111@Miscellaneous%20Nuts,%20Bolts,%20Washers

Title: Re: Leaky final drive - First Ride
Post by: not-so-fast-ed on June 27, 2008, 01:10:18 PM
Rob,  Why switch to copper?  Just asking, never occurred to me.....

 :-/

Ed
Title: Re: Leaky final drive - First Ride
Post by: Semper Gumby on June 27, 2008, 09:59:09 PM
Quote
Rob,  Why switch to copper?  Just asking, never occurred to me.....

 :-/

Ed
Title: Re: Leaky final drive - First Ride
Post by: Rob Valdez 79 R65 on June 27, 2008, 10:01:59 PM
Crushable[/b] copper washers used to be standard when the bike was new.

Ever since they switched to the flat aluminum, I have had leaks.



Or I am remembering a different life...
Title: Re: Leaky final drive - First Ride
Post by: not-so-fast-ed on June 28, 2008, 08:30:53 AM
I myself have remembered many different lives, Some actually verified....     ;D
Title: Re: Leaky final drive - First Ride
Post by: Rob Valdez 79 R65 on June 30, 2008, 01:24:41 AM
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F99448029%2Fsmall.jpg&hash=d049ec2c09721a3b559ed212bdadc2b76aaf876d) (http://www.pbase.com/tomfarr/image/99448029/medium) (https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F99451045%2Fsmall.jpg&hash=90c47b7eb56b72cda76a7766cf649cfadcc02bb8) (http://www.pbase.com/tomfarr/image/99451045/medium)(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fwww.pbase.com%2Ftomfarr%2Fimage%2F99450839%2Fsmall.jpg&hash=4e856f8b9a7b69765d65432865aeee0f7ffb88ee) (http://www.pbase.com/tomfarr/image/99450839/medium)
 
 
I blew compressed air through both vent holes.
I believe it is coming from the large one at the top.
This is after 100 miles since the clean-up.  
I saw a drop on the drain plug after work Saturday morning, but the case was still too clean to see from where it was coming.
 
After a 60 mile ride today, I saw what is in the pictures above.
 
The level in the rear drive is right where I filled it last week, at the bottom of the threads.
Title: Re: Leaky final drive - Still Leaking
Post by: nothing on June 30, 2008, 08:57:51 AM
Leaking from the vent hole and no change in fluid level could mean that you have lube migrating from elsewhere. How is the level is your driveshaft?
Title: Re: Leaky final drive - Still Leaking
Post by: Rob Valdez 79 R65 on June 30, 2008, 04:06:06 PM
Quote
Leaking from the vent hole and no change in fluid level could mean that you have lube migrating from elsewhere. How is the level is your driveshaft?

Driveshaft fluid level stays constant.