Rocker Cover install trouble...need advice

[jradvantage]

I have a 1978 650E that I'm working on.

Opened up the engine to replace the cam chain and ended up with new pistons, cam chain guide, cam chain tensioner, a cylinder re-bore, valve lapping, new seals, gaskets and elephant foot tappets. This is the first time I've ever opened up an engine.

Got everything together, except the rocker cover. Put it on before I sealed it up to make sure everything was lining up. Turns out as I turn the crank around, the rocker cover lifts off. Is that normal or do I need to shave more of the rocker off?

At TDC the left front valve tappet is tight and slightly lifts the rocker cover. Things get worse when I turn the crank.

It seems like I've shaved off enough of the rocker to accommodate the elephant feet (threads are at about 8mm deep). I'm starting to think something else might be messed up.

Any guidance would be very much appreciated!

John

 

[5twins]

It sounds like you haven't taken quite enough off that one rocker to allow it's elephant foot adjuster screw to be loosened enough.

 

[jradvantage]

Thanks for the response 5twins!

I went one more revolution around and the right front rocker has a small bit of play...that one should be ok then?

I'll take a tad more off the left front...it's real close.

Should I only be concerned with the front valves at TDC?

John

 

[5twins]

Intake and exhaust on one of the cylinders will be tight at TDC. Which cylinder that happens on will depend which cylinder is at TDC on it's exhaust stroke. The pistons rise and fall together, both reaching TDC together, but one is at TDC on the exhaust stroke and the other is at TDC on it's compression stroke. Theoretically, you could grind just the rockers on one cylinder and get the cover on, but that would give you an unbalanced valve train. Two of the rockers would be lighter than the other two.

 

[jradvantage]

Ok. That makes sense.
The valves in back (intake) both have plenty play when at their respective TDC's. The exhaust valves are very close. Once I get an equal amount of play on those tappets at their respective TDC's I should be good to go...?