Cylinder Head Removal Question R60/6

The exhaust threads on right side cylinder are stripped - I'm in process of removing the head and sending off for repair.

I've gotten as far as setting right side at TDC and am pausing for some advice - The Clymer manual shows step by step instructions on removing the head - I have vague memories of the needle bearings falling out when I worked on restoring my R65LS.

So, what do I need to not do to avoid this from happening? - the manual says 1) use a criss-cross pattern to loosen the rocker arm nuts 2) Remove each rocker arm assembly and place in a separate box - I'm taking pictures and from what I've read, one rocker arms is on exhaust side of head and other on intake. 3) remove pushrods and mark R and L and I and E for proper orientation when putting it back together. 4) Remove upper and lower bolts on head. 5) Clymers says to replace the head gasket with a new one.



Your experience and insight appreciated!

Sounds like your on the right track. I had Oak's top end manual in my hands when I did the work on my /7. Well worth it. I don't recall an issue with the rocker bearings...never had a problem. Anton has a good page on the various configurations of rocker arms:

http://www.largiader.com/tech/rockers/

Oak's manual says to find TDC on the compression stroke for the side you want to work on. He says to loosen all 6 nuts in stages...don't save the top/bottom nuts for last. As for the needle bearings, he says to not let the shafts of the rocker arms slip out. Once the pushrods are out, put the rocker arms back up on the 4 studs temporarily. Snug the nuts to 5-10 ft-lbs. Then move over the other side and find TDC on the compression stroke...should be a 360 degree rotation of the engine. Now repeat the process of stepping down the head bolts. You can then completely remove the rocker arms and head. Go back to the other side and remove the 4 nuts that were put on temporarily. Remove the head.

Not sure but you might be only removing the one head. If so, then I'm not sure how to handle this. Oak is assuming you're doing a complete top end job, and I'm not sure why he suggests snugging up the rocker arms on one side before attempting it on the other side. Uneven forces somewhere??

Anyway, hope that helps.

Here are a couple of youtube videos that provide illustration. If needles fall out of your rocker bearing, I believe that new bearings might be in order. When I removed the head from my R60/6 I did not have any needles come out. I did take some care to keep the whole rocker assembly together once the head bolts were removed from the studs. I placed each rocker assembly in a small plastic pan and that went into a plastic ziploc bag. I kept the pushrods stored so that re-assembly was in the same location and orientation as before.

A reliable torque wrench should be on-hand during re-assembly. I torqued the bolts on in a criss-cross pattern (as shown in your manual) in phases. As I recall, I used 10 ft-lb, 18 ft-lb, and finally 25 ft-lb as the values. Re-torque in 500 miles as you will be using a new head gasket.

Links to videos follow -

<iframe width="560" height="315" src="https://www.youtube.com/embed/eFH90xjZDBA" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>


<iframe width="560" height="315" src="https://www.youtube.com/embed/VideloBaw_0" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

Thanks Kurt and Rob

Kurt - just removing right head to get the threads fixed

Rob - thanks for the videos

I'm supposed to retorque the heads on right side after 500 miles - Question: I'm not removing the left head - do I need to retorque that at any time or just leave it? Worst case scenario is stripping the threads inside the heads.

Thank You!

You will want to remove the cylinder and maybe piston (if decarboning seems desirable). If you remove the piston you may wish to obtain extra circlips. It as a bit dodgey for me to re-insert the circlips the first time - one or two may still be in a dark crevice in the garage of the house that I used to own. There is a bit of a technique to re-insert the circlips, but like many things in life some practice and experience helps. Thus, the potential need for a couple of extra circlips.

My R60/6 had an aluminum gasket at the base of the cylinder. After removal of the cylinder and the base gasket, the area about the engine case was carefully cleaned. Try and keep dirt out of the pushrod lifters!

New pushrod seals, small o-rings at the top studs will be desirable. I believe that BMW used to recommend Hylomar as a sealant for the base of the cylinder - I have used Hylomar in the past. But, more recently folks seem keen of HondaBond (or YamaBond). Whatever you use it is best to use a very thin coating - do not gum up to top holes in the cylinder (which the engine studs pass thru). The o-rings and holes about the studs allow passage of oil to lubricate the rocker assembly.

Snobum has written quite a bit about this - but it can be difficult to read at a computer screen. Dive in -

http://bmwmotorcycletech.info/technical-articles-list.htm

More targeted to head removal -

http://bmwmotorcycletech.info/break-in.htm

I think you should retorque the left side one time when you get there. Might as well start both sides off with known torques. Just back off the left side nuts about 1/4 turn and bring back to 25 ft-lbs. The right side might change, though. As you go through the retorques on the right side, I'd just check the lefts...I would use the torque wrench and if it takes 25 ft-lbs without the nut moving, I'd say you're good...I'd leave it alone.

My pistons and heads needed complete de-carboning. I used Oak's recommendation and got HydroSeal-II (sold by Gunk). Thus, I ended up doing both sides.

Since you are just doing one side, you may be able to get by with just re-torquing that side. I am sometimes anal about these things and tend to over-think the issue.

Once the head is re-torqued, the valves re-adjusted, it is time to re-sync the carbs. What if you just do one side? Will the carbs still need to be re-sync'd? See, I told you I'd over-think the issue

20774 said:

... I'm not sure why he suggests snugging up the rocker arms on one side before attempting it on the other side. Uneven forces somewhere??

Click to expand...

Oak's method allows you to de-torque the head while there is no valve spring pressure on it. After the pushrods are removed no spring pressure can build, and the head bolts are lightly torqued to hold everything in place while the other side is de-torqued. If you did not do this, the first side could disassemble itself when you do the 360 degree rotation to being the other side to TDC compression.

I had my exhaust spigots repaired this winter. The shop warned me that the valve guides are typically worn and should be checked. They were correct and both the valves and guides needed redoing. One more thing to worry about...

Thanks guys for the info and videos - pulled the head off successfully this AM - bike only has 25k on the odometer - everything seems to look good

BTW, I should have mentioned that checking and probably replacing the pushrod seals might be a good idea as well. Once the heads are off, you're 80 percent there.