Top End Help

[hudson]

Ok Guys I am losing my mind putting my 71 75/5 back together. I have read over Oak's manual and other helpful suggestions on forums and internet.

I just got my cylinders back - they recut valve seats, replaced valve guides & new rings. Everything else just needed a good cleaning. Installed the left side on bike, no problem. Turned real wheel 1 full revolution to "OT" mark. Now the right side, problems. Here's the problem:

After I successfully put the Left cylinder head back on, I rotated the rear wheel one revolution to the OT mark. Installed the RIGHT cylinder head the same as I did the left. The problem is there is no valve lash - the rocker arms are tight against the valves, no gap. Everything is bound tight when I torque to spec (26 lbs). The pushrods don't spin. There is no room between their tips and the rocker arm, even when I turn the adjusment screw back to its furthest to allow more room. Its like it is in a deadlock or something.

I have checked the valve lifters - they are ok and well lubed.
The rocker blocks are on with the raised boss facing out.
The valves look to installed properly and their rims rise just slightly above the seats (these were done & installed by the BMW shop, not me).

Here is my procedure:

Installed new rings on pistons. Lubed piston and sleeve and installed into sleeve. Light hylomar on cylinder base gasket/shim. Light hylomar on back of cylinder sleeve base (that rests against the shim). Placed cylinder with piston onto cylinder studs. Inserted wristpin through piston and connecting rod with circlip. Gently pushed up to block. Put on clyinder head gasket the right way. Installed head onto cylinder. Placed rocker arms in sleeves. Put on rockers with raised boss outwards. Drew up bottom of cylinder base by tightening to 5 lbs torque. Aligned rockers and in 4 adjustments torqued to 26 lbs.

I am sitting here scratching my head. This is not rocket science once you get the procedure down. Maybe I wasn't on the compression stroke when I began on the left side like I thought. Would that mess it up? What amd I missing? What would cause this to be bound tight and not have room to adjust? Any suggestions?

[Kurt in S.A.]

That was my first thought...was it OT on the compression stroke. I would verify the left side was on the compression stroke and go from there.

The other thing...did the pushrods settle properly into the tops of the lifters? I believe there's a semi circular area for them to set.

Kurt in S.A.

[hudson]

The pushrods seem to settle in properly. They hang out approx. one inch from their holes on each side. So if I put on the left side without verifying if it was on the compression stroke, it could mess up the right side, knocking off my proper clearances/adjustments? If so, I probably did something stupid like that...

I guess I have to start all over - take off the left side & make sure it is on the compression stroke, then do the same for the right side....

[Major Softie]

OR...

Perhaps you turned it more than one revolution???

[hudson]

I get what you're saying. I went very slow to make sure. I thought the same too, so I did it several times checking each time. That's why I am puzzled. I just have the feeling it something I am overlooking in error and not a mechanical issue.

[Garnet]

Before you take anything apart turn the engine one more time and then re-check both sides.

[George Ryals]

Turn the engine slowly watching an intake valve. As the intake vavle is closing, start watching the timing hole for the OT mark to come down into view in the hole. That cylinder is now at tdc on the compression stroke. Adjust both valves on that cylinder. turn the engine one revolution(not the rear wheel), now the other cylinder is at tdc on the compression stroke. Adjust the valves on that cylinder. You're done!

[hudson]

George - I have my bike in 4th gear and rotating the rear wheel rotates the flywheel. I was under the impression this accomplishes finding TDC through the sight hole as the rear wheel is slowly spinned. On the cylinder successfully installed, I hear air coming up through the spark hole plug. Rockers become slightly loose and their is the valve lash gaps. I turn the rear wheel slowly one revolution, the other clyinder should be on TDC. But the valves are tight as hell and no room for adjustment whatsoever! What gives?

I appreciate your responses. I really do. Just frustrated when this is a fairly easy task...

[esman100]

Hudson, reread George's post slowly. He is right on the method that I've used for years.

[Major Softie]

George - I have my bike in 4th gear and rotating the rear wheel rotates the flywheel. I was under the impression this accomplishes finding TDC through the sight hole as the rear wheel is slowly spinned. On the cylinder successfully installed, I hear air coming up through the spark hole plug. Rockers become slightly loose and their is the valve lash gaps. I turn the rear wheel slowly one revolution, the other clyinder should be on TDC. But the valves are tight as hell and no room for adjustment whatsoever! What gives?

I appreciate your responses. I really do. Just frustrated when this is a fairly easy task...

George, if you truly are turning the rear wheel one revolution, then this is your problem. That does not place anything at TDC. You can use the rear wheel to turn the crank, but one revolution of the rear wheel doesn't mean anything to TDC placement. Use the technique explained in George's post and your problems should be over.