Working on the engine - internal top-end rust

[Deleted User 287]

I just wanted to get your opinions.
This is a 1981 R65 engine with @ 38k miles on it.
I got it from a non-BMW breaker in the Washington D.C. area.

This is the exhaust rocker arm pivot on the left side. The intake on this side is smooth & oily.



I am replacing the push rod tube seals, and had planned on leaving the heads attached to the cylinders.
I've yet to remove the cover from the right-hand side.

Thanks.

[Deleted User 287]

The right side shows rust, too, on both rocker arms pivots. Not quite as severe, though.

The bottom end of the pivots are clean of rust.

[Deleted User 62]

Rob, what does the bore look like through the sparkplug hole? Have you run this engine?

[Deleted User 287]

I will go ahead and pull the cylinder off the piston. I just realized I needed stud & cylinder base o-rings anyway.

I have run the bike from Indy to Columbus, OH and back. 300+ miles.
The only mechanical problem I had on that trip was the right side of the bike was covered with oil (the outside of the "inside" of the saddlebag & carrier). I'm not sure if it was from my leaky final drive (it was up to level before I left Columbus) or if I had over filled the crankcase and it was dumping out my vent that is back there.

BTW, I am ditching that crankcase vent for a more traditional catch tank.

I think I will take a good look at the pushrod followers, too.

[Deleted User 287]

Rob, what does the bore look like through the sparkplug hole?

I pulled the L-H cylinder.

No rust, but there is some (IMO) pretty bad scoring on the bottom:


click on img for larger

Nikasil cylinders.

[Deleted User 287]

It is the R-H cylinder that has me concerned.
Close-ups available here http://www.pbase.com/tomfarr/nikasil_engine_interior

6 o'clock:



exhaust side



intake side

[Rob Frankham]

Sorry mate but that looks pretty horrible to me. Worse because they are Nikasil jugs so they can't really be bored out. Any chance of any recompense from the vendor?

Rob

[Deleted User 287]

Any chance of any recompense from the vendor?
Rob

No, I bought the engine 2, or was it 3 years ago.

[Rob Frankham]

Oh, sorry to be a Jonah but... don't see any future for those jugs...



Rob

[Deleted User 287]

Looks like I'll be parting this bitch out, after all.

If I were to go to the trouble of buying replacement cylinders, I suppose it would be foolhardy not to replace the rings as well?