Engine seal leak

[atericel]

Hey Camheads-

 

2012 RT rider here... After a quick overnight trip down to Southern Utah via Route 12 a couple of weeks ago to enjoy some of the last of the nice fall weather, I backed my bike into the garage. A couple of minutes later, I came out to unload the bike, and noticed a couple of drops of oil underneath the bike, near the back of the engine. Family schedule required the bike to sit for a few weeks before I could take a closer look. Yesterday, I took off the left side fairing to get a better look, hoping it was the left side cam chain tensioner bolt that is sometimes a bit loose, and can leak. It was bone dry. It looks like it is leaking where the transmission meets the engine. Just a few drops, but the back of the gear box is "wet" with oil. I am pretty sure it is engine oil, as it does not smell like gear oil.

 

So I've started down the research path of splitting the bike in two and replacing seals, and possibly the clutch, if it has been contaminated with oil. I've found some threads detailing this process on a GS (on ADVrider), and a couple of youtube videos as well, also on GS's. While I can tell this is a difficult job, I think it is within my ability.

 

The Haynes manual suggests that some of the new seals can be pressed in with an appropriately sized socket. However, the steps to reinstall rear main crankshaft seal call for a BMW tool, specifically parts numbers 115701, 115702, 115703, and 115705. I have scoured the internet for a few days, and I cannot find these for sale ANYWHERE, including on Beemer Boneyard, Wunderlich America, and Beemershop.com.

 

Has anyone out there found a way to fashion another tool that works? Or know where to buy the tool? Alternatively, would anyone be willing to rent to tool to me (with a deposit?) through the mail? I am hesitant to tear into this project before knowing that I can actually complete it and get the seals back in properly. I welcome any words of wisdom, links to helpful threads, or holy incantations you might have to offer.

 

Thanks,

atericel

Edited October 30, 2023 by atericel
Edited for clarity

[dirtrider]

13 hours ago, atericel said:

Hey Camheads-

 

2012 RT rider here... After a quick overnight trip down to Southern Utah via Route 12 a couple of weeks ago to enjoy some of the last of the nice fall weather, I backed my bike into the garage. A couple of minutes later, I came out to unload the bike, and noticed a couple of drops of oil underneath the bike, near the back of the engine. Family schedule required the bike to sit for a few weeks before I could take a closer look. Yesterday, I took off the left side fairing to get a better look, hoping it was the left side cam chain tensioner bolt that is sometimes a bit loose, and can leak. It was bone dry. It looks like it is leaking where the transmission meets the engine. Just a few drops, but the back of the gear box is "wet" with oil. I am pretty sure it is engine oil, as it does not smell like gear oil.

 

So I've started down the research path of splitting the bike in two and replacing seals, and possibly the clutch, if it has been contaminated with oil. I've found some threads detailing this process on a GS (on ADVrider), and a couple of youtube videos as well, also on GS's. While I can tell this is a difficult job, I think it is within my ability.

 

The Haynes manual suggests that some of the new seals can be pressed in with an appropriately sized socket. However, the steps to reinstall rear main crankshaft seal call for a BMW tool, specifically parts numbers 115701, 115702, 115703, and 115705. I have scoured the internet for a few days, and I cannot find these for sale ANYWHERE, including on Beemer Boneyard, Wunderlich America, and Beemershop.com.

 

Has anyone out there found a way to fashion another tool that works? Or know where to buy the tool? Alternatively, would anyone be willing to rent to tool to me (with a deposit?) through the mail? I am hesitant to tear into this project before knowing that I can actually complete it and get the seals back in properly. I welcome any words of wisdom, links to helpful threads, or holy incantations you might have to offer.

 

Thanks,

atericel

Morning   atericel

 

The good or maybe bad news is, on the 1200 rear engine oil leaks I almost always find the rear balance shaft seal leaking, or find the oil leak due to a slightly loose rear balance shaft counter weight. 

 

On the rear main seal install ? -- The first one I did years ago I used a doubled up piece of clear packing tape (sticky side to sticky side) then wrapped around the crankshaft to get the seal started on the crankshaft (after I first pushed the seal onto a tapered plastic cup to sort of form/size the seal inner lips). 

 

Then I drove the seal into the engine case using a metal cup type oil filter wrench- It was a real pain to get the seal installed straight & to the proper depth, no doubt about it, but with effort &  finesse I got it installed.

 

Since then I have only installed a couple of 1200 rear seals & for those I had access to the proper BMW seal installing tools. Made the job much easier & pretty well fool proof. 

 

Are you sure your leak isn't clutch hydraulic fluid from a leaking slave cylinder (is the clutch reservoir still full?). 

 

 

[atericel]

Thanks, dirtrider. I'll check the slave cylinder, and report back.

[atericel]

Unfortunately, the clutch slave cylinder appears to be ok, and fluid level in the master cylinder seems normal.

 

I am guessing I will have to split the bike open, and check which seal(s) is/are weeping, and then order parts from there. Hopefully the clutch isn't fouled up, but I'm not holding out much hope.

[dirtrider]

44 minutes ago, atericel said:

Unfortunately, the clutch slave cylinder appears to be ok, and fluid level in the master cylinder seems normal.

 

I am guessing I will have to split the bike open, and check which seal(s) is/are weeping, and then order parts from there. Hopefully the clutch isn't fouled up, but I'm not holding out much hope.

Afternoon atericel

 

It sort of depends on the seal & how it is leaking. 

 

Typically, if it is the rear main seal then that tends to leak more while riding (engine running).

 

If it is the balancer shaft seal or loose balancer weight then those tend to leak more after the ride, plus it is lower down so it doesn't tend to foul the clutch. 

[jdub53]

53 minutes ago, atericel said:

 

I am guessing I will have to split the bike open, and check which seal(s) is/are weeping, and then order parts from there. Hopefully the clutch isn't fouled up, but I'm not holding out much hope.

 

FWIW, the maintenance records for my '13 RT that I bought last year show that two years prior a dealership had replaced the rear main seal due to leaking and the clutch was fine.

 

The counter balance shaft seal on friend's new 2012 GS was replaced twice under warranty within the first 5,000 miles due to leaking, and no ill effects to the clutch either time

 

Point is, any rear seal leak doesn't automatically mean clutch friction disc oil contamination.

 

Good luck with yours.

[atericel]

20 minutes ago, jdub53 said:

 

FWIW, the maintenance records for my '13 RT that I bought last year show that two years prior a dealership had replaced the rear main seal due to leaking and the clutch was fine.

 

The counter balance shaft seal on friend's new 2012 GS was replaced twice under warranty within the first 5,000 miles due to leaking, and no ill effects to the clutch either time

 

Point is, any rear seal leak doesn't automatically mean clutch friction disc oil contamination.

 

Good luck with yours.

Thanks, jdub53. I am hoping that will be the case. I am trying to decide if it will be worth it to do the other seals, and maybe replace the clutch using one of the oil resistant plates while I'm in there. I'd like to avoid the extra cost, but I'd also like to avoid tearing this thing apart again for awhile, too.

[dirtrider]

24 minutes ago, atericel said:

Thanks, jdub53. I am hoping that will be the case. I am trying to decide if it will be worth it to do the other seals, and maybe replace the clutch using one of the oil resistant plates while I'm in there. I'd like to avoid the extra cost, but I'd also like to avoid tearing this thing apart again for awhile, too.

Afternoon atericel

 

I can't advise you on using an oil resistant clutch disk but can say to get a couple of endorsements on the one you want to use  from riders that have gone that way.

 

In my experience some oil resistant clutch disks have a tendency to chatter on launch. 

 

I have a friend that has a 2005 1200RT that has had an oil seep at rear of engine since almost new (about 80,000 miles ago). I'm not sure if it is a rear main seal or a balance shaft seal (but most likely a balance shaft seal or that area anyhow). The clutch still locks up strong).

 

In your present case it does sound like you more than a seep so that could be worse on the clutch than his seep.    

 

Remove the starter then look into the clutch cavity, if there is a lot of oil thrown around then you probably have a contaminated clutch disk. 

[Dave_in_TX]

3 hours ago, dirtrider said:

Afternoon atericel

 

I can't advise you on using an oil resistant clutch disk but can say to get a couple of endorsements on the one you want to use  from riders that have gone that way.

 

In my experience some oil resistant clutch disks have a tendency to chatter on launch. 

 

I have a friend that has a 2005 1200RT that has had an oil seep at rear of engine since almost new (about 80,000 miles ago). I'm not sure if it is a rear main seal or a balance shaft seal (but most likely a balance shaft seal or that area anyhow). The clutch still locks up strong).

 

In your present case it does sound like you more than a seep so that could be worse on the clutch than his seep.    

 

Remove the starter then look into the clutch cavity, if there is a lot of oil thrown around then you probably have a contaminated clutch disk. 

When my 2011 RT needed a new clutch at 110k miles, I went with Siebenrock oil proof clutch plates. It worked fine and I didn't experience any chatter on launch with it.

[jjpen]

can the balance shaft weights be tightened without opening the engine?

[jdub53]

 

23 minutes ago, jjpen said:

can the balance shaft weights be tightened without opening the engine?

 

Yes, but the gearbox must be removed to access it.

 

You can just see the balance shaft weight at bottom center of the pic below from my old '07 GSA; behind the flywheel and below the clutch pressure plate.

 

 

The pic is from when I pulled the gearbox at 68k miles to check and grease the clutch splines. Full details and more pics in this thread I made at the time:  https://www.advrider.com/f/threads/my-r1200gsa-step-by-step-gearbox-removal-process.655998/

[dirtrider]

1 hour ago, jjpen said:

can the balance shaft weights be tightened without opening the engine?

Morning  jjpen

 

As jdub53 mentioned the transmission must be removed first. But there is more to it than just tightening the balancer weight bolt. (torque to 10nm then an additional 90° of bolt head rotation) 

 

That long balance weight bolt is a one-time use bolt so it should be replaced if loose or removed.  

 

Plus, if you are going in that far for a balance shaft area leak  (trans removal) then you really want to also replace the bolt & seal. 

 

It's not mentioned in the service manual but I usually put a very light smear of sealer on the bolt head to balancer weight interface as oil can wick out along the bolt so using a bit of sealer prevents it seeping at the bolt head to weight interface. 

[atericel]

8 hours ago, jdub53 said:

 

 

Yes, but the gearbox must be removed to access it.

 

You can just see the balance shaft weight at bottom center of the pic below from my old '07 GSA; behind the flywheel and below the clutch pressure plate.

 

 

The pic is from when I pulled the gearbox at 68k miles to check and grease the clutch splines. Full details and more pics in this thread I made at the time:  https://www.advrider.com/f/threads/my-r1200gsa-step-by-step-gearbox-removal-process.655998/

Ha! Your thread on advrider is one I had found and bookmarked to help me with my job, so thank you! I don't know what people did before they could find this stuff on forums.

[jdub53]

11 hours ago, atericel said:

Ha! Your thread on advrider is one I had found and bookmarked to help me with my job, so thank you! I don't know what people did before they could find this stuff on forums.

 

Glad it helped you. When I did that job I decided to document it and made the thread to pay forward all of the helpful information I'd gotten from others along the way. I also used it as a reference when I split that bike again and changed the clutch at 133k miles. 

[atericel]

Hey y'all-

 

I finally got the bike split in 2 today, and got the clutch off. The main seal was definitely the culprit, but I will also be doing the counterbalance seal and bolt since I'm already this far.

 

My question at this point is whether or not to replace the clutch. Basically, I don't know what I'm looking for. I do not smell any scorched oil on the friction plate and it is measuring about 5.8 mm thick. However, a former mechanic friend looked at some pictures of the pressure plate, and was concerned about possible heat spots. I don't see any scoring on there. Does this clutch look ok to put back in the bike? Or do you guys think should I pony up the $650 and get a new clutch assembly ordered?

 

[Hati]

The way I look at it (and this is just my personal opinion) is how much did I enjoy getting to the clutch. I do like working on my bikes almost as much as riding them. If you don't mind (at least) splitting the bike, leave the clutch alone as long as it was not slipping at all before you pulled it all apart.

 

If you rather have needles pocked in your eyes than do the job again, spring for a new clutch plate. I don't know what the factory minimum spec is for the flywheel thickness, but certainly with those scorch marks visible on the photo, I would not be changing it out. The clutch itself seems to have a lot of meat left above the rivet heads, so even that doesn't look like it needs to be replaced just yet.

 

If you mostly ride long distances with little clutch use, just put it all back together. If you commute, replace the clutch plate.

[jdub53]

The friction disc minimum thickness was 4.4 to 4.6mm for my '07 Hexhead, and the new disc I installed on that bike at 133k miles was 6.35mm. Assuming the dimensions are the same for your Camhead, there's a lot of service life left in your friction disc.

 

No way to know for sure of course, but any spots on the pressure plate may have occurred when the bike was fairly new and have been there without affecting clutch operation ever since. If the clutch has been working fine, I'd probably just reinstall everything.  

 

My '07 GSA's pressure and cover plates had marks and light surface cracking when I removed them (likely the result of some challenging situations off-road), but were still working perfectly:

 

  

[Lowndes]

FWIW - Several years ago I replaced the friction disc on my '99 R1100S because of a failed slave cylinder and the resulting DOT4 on the clutch that destroyed the OEM friction plate.  I used the regular Siebenrock ($100), not the oil-proof ($250) at the time.  It is still working very well.

 

https://www.beemerboneyard.com/2123737bp.html   Unfortunately, BBY says they are "Temporarily out of stock" on these.  Might contact them for availability and alternatives.  They are really good to deal with.

[atericel]

Thanks, everyone. I think I'm probably going to just put this clutch back in. FWIW, the splines appear to be in good condition, though I will clean and lube them.