Boxerworks.com

Tim Shepherd wrote:

Major Softie wrote:Do I see rust on the valve retainer and, perhaps, on the valve spring?

I checked again, and I think the yellow/brown patch you are referring to on the retainer is the reflection of the ceiling light in my living room. Also, the retainers appear to be some kind of alloy, not steel. Close inspection of the springs with a magnifying glass shows no rust, some blue paint though. The bores are showing cross hatch marks and there is oil on the bottom. The inside surface of the head and cover are dry, but the rockers etc all have an oily feel.

Titanium retainers probably. I've got a psychic feeling you've got a good one. You could tare it all down to inspect the internals, but you'll end up spending half or more of that $800+ putting it back together again. You might want to do a visual check of the rear main seal and PR seals. You could easily be wasting money replacing good seals and gaskets....that's a call you have to make when you buy a put together motor.
You can tell if you've got a 336 cam by measuring the lift at the pushrods. http://moragafalconers.org/BMW_336_cam/
If you think it hasn't been run make sure you do a 2500 rpm cam break in at start up. I'm sending you positive vibes.

Thanks for that link! It's been awhile since I've broken a motor in... What other tips can any of you give me for proper break in? Multiple oil changes early on is a given.

mattcfish wrote:Not sure why you would need to wire the filter cover screws. There's more of an issue with them sticking than backing out.
Maybe the PO wanted to save the threads (or had damaged them in the past) by using extremely low torque.

racers do that. Almost all bolts need to be wired like that so they won't fall out onto the track and create a hazard for other racers.

Because it has that racing touch.... there might definitely be some internal goodies in there....

jjwithers wrote:

mattcfish wrote:Not sure why you would need to wire the filter cover screws. There's more of an issue with them sticking than backing out.
Maybe the PO wanted to save the threads (or had damaged them in the past) by using extremely low torque.

racers do that. Almost all bolts need to be wired like that so they won't fall out onto the track and create a hazard for other racers.

Because it has that racing touch.... there might definitely be some internal goodies in there....

Good point. Could be to meet vintage race requirements. How many cc's is it?

All I know is it's built on an early /5 block #2975775. I believe that makes it a R75/5 block originally. Someone wrote "torqued to 46 ftlbs" on the flywheel. I wish I knew whose trademark that was.

Tim Shepherd wrote:Thanks for that link! It's been awhile since I've broken a motor in... What other tips can any of you give me for proper break in? Multiple oil changes early on is a given.

Everything's out the window on break in. The only consistent theme I've heard is to vary your RPM's and avoid reving to the high end of the RPM range. Work harden the cam and lifters together at 2500 RPM for 10 to 25 minutes without over heating your motor. Then get on and drive it. Some suggest loading it to get the rings to spin, while others say not to load it. Don't baby it or you'll glaze your cylinders and the rings won't bed in. Use oil with ZDDP in it like Valvoline VR1 racing.
Some change their oil after 20 minutes, some after the first 100 miles, some wait until the designated oil change. I do the first change at 500 and a second at 1000. I've never had oil burning issues. Of course I've also disregarded all of the above and had no problems, so I think luck is also an important factor. There's lot's out there on the subject.

Tim Shepherd wrote:All I know is it's built on an early /5 block #2975775. I believe that makes it a R75/5 block originally. Someone wrote "torqued to 46 ftlbs" on the flywheel. I wish I knew whose trademark that was.

If you pulled those flywheel bolts and found that they were 11mm instead of the /5 10mm bolts, you'd know that some attention had been paid to bottom end details and probably a full bottom end rebuild was done. I think a torque of 46 lbs would be a /5 bolt torque. The later 11mm bolts are torqued quite a bit higher. Still, the fact that it was written on the flywheel shows some of the anal detail the PO or builder put into the motor.

Tim Shepherd wrote: and the oil filter covers bolts had been drilled and wired.

Most racing organizations require that any fastener with positive fluid pressure behind them must be safety wired.
It's possible that the threads in the block are fine.
Have a good look/see, and if the threads are suspect, just go "snug" and use ss safety wire.