Broken rocker arm pivot - got lucky?

[givory]

After trying everything to source a left side oil leak on my 2L/6 914 vintage racer that sprayed all over, but only at speed on the track, I finally traced it to a cracked rocker arm pivot [right name?]. I think I got very lucky as the bolt fell out and was sitting in the valve cover, but the pivot never budged - even after a 3day race w/e. Is this a common problem? Could the crack point to other problems?
Thanks
Gavin [...hoping this board automatically resizes pics - we'll see!]

[ChrisBennet]

I can't see the crack. Trying downloading Irfanview and resize or crop the picture and repost. I use MS Paint to add arrows or circles.
-Chris

[hkspwrsche]

The rocker arm shaft is the name for it.... did it crack on one end where the bolt and cones are supposed to squeeze it open on the end? If thats the case it could have been over tightened maybe? It doesnt specify a lot of torque if I recall correctly. Its easy to put 50 ft/lbs on something that should take 20 ft/lbs if your not using a torque wrench. When was it last apart and who did the work at the time?

Harold

[Bobboloo]

It looks to me like it cracked on the inside of the groove cut for the expanding end. I've seen this on the motor I'm presently finishing rebuilding. Infact several shafts were broken I believe by an over zealous wrench. I guess he wanted to make sure that they didn't leak oil.

Next motor I build I'm gonna make sure non of the shafts have any cracks because they can really get stuck and it's a b*tch to get them out without burring the cam tower.

[givory]

... sorry guys - I posted, then had to leave for vacation. I'll resize the pic and throw in a pointer, tonight when I get home, but thanks for the suggestions. It's back together [not run yet]- with some good help. But what an oil mess: 6weeks on stands with all oil drained, and the engine compartment is still dripping.
Gavin

[givory]

...here's a smaller version of the earlier pic [lousy focus] , with the crack circled. It runs cleanly all the way through the shaft, which fortunately never budged. The bolt and the nut were sitting in the bottom valve cover.



I think all is OK now. Not a terribly exciting story ... !
Gavin
VARAC #58

[givory]

geez ... I thought I got that pic to 800x600. I'll stick to opening email.

[Wayne 962]

We webserver resizes images for the BBS. Does your camera have a "macro" setting? Macro means "close-up".

-Wayne