Join Date: Jul 2012
Location: Granbury, Tx, USA
Broken cam bearing cap stud
I could really use some help on this one.
Looks like who ever did the maintenance before me may have been a bit overzealous with the tightening tool.
I THINK I used extreme caution since this is my 1st beemer bucket change and the associated paranoia was keeping me company.
Read the manual, 3x. Watched the vids until my eyes wouldn't focus, so I have the procedure but still have this mess. To be semi certain I read and watched again and again during the last week while waiting on parts to arrive.
Doing the valve check, new buckets as needed, and this morning went to install the cam and bearing caps. Everything went swimmingly during disassembly.
Install the cam with as many lobes clear of the lifters as can be managed, and begin tightening the caps sequentially, starting from the center and doing this in increments with just a socket and my hand, no wrench.
Everything is going well and we come to the part where a wrench is required to turn the nuts, but they are still nowhere near torque value. ( Studs are DRY btw )
Had the wrench set to 80 inch pounds per Clymer, tested on the exhaust cam caps that I did not remove and the wrench clicked without turning the nuts, so I think I'm Ok.
Re-check the torque wrench and begin slowly/sequentially tightening the cap nuts. Periodically check the wrench against the exhaust cap nuts and all is well.
The intake cap nuts/studs will not tighten. No matter what I do they won't torque. I'm doing this in 1/8th turn increments and placing no force on the wrench. I noticed the amount of stud protrusion beyond the nuts was longer than on the exhaust cam studs.
Finally I take a sharpie and mark the end of the studs and find they are turning. As I go to remove all the caps, the number 3A intake stud breaks, leaving me with about 5/8ths inch to work with for extraction.
What's the best way to remove these studs? Is heating or pulling the head required? At this time I had best replace every one of them.
BMW; Brought My Wallet.