R80RT Pulled Cylinder Stud?

[gog]

My pushrod tube seals on both sides are weeping oil and its getting pretty manky. I know this is pretty common but I would like to fix them, they look like the seals have not been changed in a while.

I have ordered new pushrod tube seals and all the necessary gaskets/o-rings for barrel & head removal and plan to do the job at the weekend. However, one of the studs (LHS) is suspect, looking like it has pulled out too far during torquing and then been cut off. Im worried that this will be an issue, perhaps pulling right out when i retorque the heads after removal.

Pics below of both sides, RHS looks fine to me but LHS not so much.

Any thoughts or advice before I take it apart? The bike is running fine as it is, compression seems ok and seal leaks are not catastrophic, I need to top up every month but never much and theres no apparent drips on the floor when bike is on stand.

 

[bumpmuncher]

If its running fine and not covering the back wheel in oil. Leave it alone untill it needs doing. ride and enjoy, its part of their character

 

[gog]

With the possibility of drills, jigs, timeserts and headaches, theres a good chance thats just what's going to happen

 

[chrisshrops]

here we go buddy ,just the thing for you ,he also does a pushrod seal vid too
http://www.youtube.com/watch?v=zSaQzFpzxpA

 

[gog]

Cheers Chris. I have watched all of their service vids before and theyre very good. I like the guy's attitude.

I dont have either the funds nor correct tools to repair what could potentially be more than one knackered thread in the block. I also posted the issue over on advrider and general consensus seems to be if the bike is running fine and not pissing oil all over the place, leave it until it cant be avoided any longer. Im leaning towards taking that advice for now since the bike is my daily commuter.

 

[Rob Farmer]

Looking at the picture of your right hand cylinder. I can't see the dots that should be on the top and facing outwards. It could just be the angle in the photo though. If the dots somewhere else your rockers will be starved of oil.

 

[gog]

hi rob, I'm not sure i understand what dots youre talking about - are these the oil channels that should run along the studs? would appreciate if you could explain whats supposed to be there and where. you have me a bit concerned!

 

[Rob Farmer]

There's a dot on the end of the rocker shaft that needs to be on the top and facing outwards. It could just be the photograph but I couldn't see them on the picture of your right hand cylinder head.

 

[gog]

cheers for pointing that out rob. I'll take the covers off tomorrow, check the holes are there and post close up pics.

 

[Sean Kelly]

On my RTW trip 10 years ago, I came across 3 x GS who all had studs pull out at some time during their travels. Including mine of course. A bull nose stud was fitted but the repair didn't last. These bikes had all been running in very hot climates for lengthy periods and it was always the exhaust side. I reckon people torquing to the max and without backing off first is the cause. I did hear that BMW had reduced the max torque settings in a service update but have no evidence of this other than hearsay. If fitting inserts, the oil way in the hole needs to be clear.

 

[Rob Farmer]

Bmw sell an insert for the job.its a longer insert with an open thread to allow the oil through. The drilling is the awkward part. Dan at cycleworks sells a jig for the job http://www.cycleworks.net/index.php?main_page=product_info&cPath=29_33_51&products_id=20 I've dealt with cycleworks several times, they are excellent to deal with.

 

[gog]

Thanks for the link and recommendation. I wasnt aware that the studs pulling out was such a common issue but I cant say im surprised. I have found things that have been done incorrectly with almost every job that I have taken on on this bike, one (or several) of the previous owners just didnt give a crap as long as it ran. It is an ex police TIC model - clock says 58K but christ knows the true mileage.

I will carry on fixing and servicing bits as I go. Its a great bike to work and learn on and it owes me nothing.

 

[Rob Farmer]

They're nice bikes once they are sorted out, unfortunately there's still a massive legacy of mechanical abuse from when they were cheap winter hacks.

 

[Steptoe]

Thanks for the link and recommendation. I wasnt aware that the studs pulling out was such a common issue but I cant say im surprised. .

Very common, especially on post 84 bikes.

Easiest and best method to fix is to use a wurth timesert, and then drill out the hole for the oil way.
Once done will last a lifetime.

I've seen some horrendous bodges fixing this problem, including a spark plug body used as an insert

 

[gog]

Im going to clean the area thoroughly and monitor the problem. When i do remove them, if they are knackered Im considering buying a used block with good threads and swapping the whole lot over. Could be a 'deep end' learning exercise. Theres one on ebay in good nick just now for £100 which sounds cheaper than a repair would be.

Rob, I think the dots you mentioned yesterday are present and in correct position. I found some old pics (ignore the completely out of whack valve!) which seem to show what im assuming you were referring to as correct:

 

[Steptoe]

Theres one on ebay in good nick just now for £100 which sounds cheaper than a repair would be.

That's not cheaper than fixing the problem using a timesert. And that's before you get to the work involved swopping everything over and gaskets.
Plus how will you know if the bottom end is any good ?

 

[gog]

You have a point about not knowing how good the internals are, it would admittedly be a bit of a gamble.

I appreciate that the timesert itself wouldnt cost that much but to do the job right its apparent that I would need to buy or rent a jig or risk buggering things up even further with a wonky drill job. Im sure that a jig is necessary to get it absolutely true, has anyone that you know of done it successfully freehand?

 

[Steptoe]

Im sure that a jig is necessary to get it absolutely true, has anyone that you know of done it successfully freehand?

I've only ever done it freehand and so has anyone else i know who's done the same job. It's pretty straighforward.

 

[gog]

that's good to know, thanks. would best bet be to contact nearest bmw dealer for the insert? not seen them for sale in the usual places (motobins etc)

 

[Steptoe]

that's good to know, thanks. would best bet be to contact nearest bmw dealer for the insert? not seen them for sale in the usual places (motobins etc)

Wurth make timesert kits in all different sizes and are nothing to do with BMW.