Piston Connecting Rod Hit Housing

[mdecnsp]

My son was given an 83 R65LS from his cousin's grandfather. It does not run. The last time it ran he was told that the oil shot out of it. Not exactly sure what that means yet but I'm sure that it at least needs new valves, valve guides and piston rings. We're starting to tear down the engine and when we took the pistons off the connecting rods, the rods dropped and hit the engine housing. How hosed are we? I've attached a couple of picts of the housing. How do we fix this damage?
We're new to motorcycles and to this site so sorry if this has been covered before.  [smiley=bmw_smiley.gif]

Thanks ahead for any advise.

[steve hawkins]

The picture you show implies that what you actually mean are the pushrod tubes and perhaps the rubbers.  It seems to indicate that perhaps you might need new tubes and rubbers.  The tubes do corrode and the rubbers do perish or harden.  The oil they carry comes back from the heads and drains back into the engine.  So , yes oil will leak from them given half a chance.

Pushrod tubes can be had in stainless steel, or the standard variety.  New rubbers are recommended and have to be fitted the right way up.

Cheers

Rev. Light

[marcmax]

I think the area in question is the small cylindrical depression on the edge of cylinder base opening. I wouldn't think that would be a problem.

[Ed Miller]

I agree with marcmax but I'd sure like to see how the rod fared in that encounter.  I would be more worried about it.

[nhmaf]

Generally the rods are steel and much harder than the alloy cases - hence the ding.   But, they are not indestructible either.

I *think* you may still be OK, though I might *carefully* use some very fine emery cloth and go lightly on that spot to at least make sure that there aren't raise edges / sharp corners on the depression.
I think that the  base o-ring and the usual THIN schmear of Yamabond on the case where the cylinder butts up against it (mind you don't get any in /near the top two cylinder studs as there is a small oil galley passage there to keep the rocker bearings lubricated) will handle this level of imperfection.

[steve hawkins]

I was too focused on the 'oil shot out of it' sentence and can now see what you mean.

I have only had one time when the 'oil shot out of it' happened on my bike.  And that was when I left the fuel tap on over winter.  Much fuel got into the oil and the crank case was then over pressurized and a load of oil squirted out of the breather and anywhere else it could come out.  Fortunately, I only ran the motor for a very short while.

The fix was an oil and filter change, followed by never leaving my fuel tap on.  A replacement tap was eventually procured.

I would not be that worried on the 'little dent' though.

Rev Light

[montmil]

One of the old Airhead gurus, Das Snowbum, will tell you to carefully dress out the ding so that the cylinder can be refit without excessive force. Note the cylinder's base has a large diameter o-ring that seals the crankcase joint. There are also two small o-ring for the upper crankcase stud, but that's another story.

Rods are hard steel. Seriously doubt that they/it incurred and damage. If you visually inspect the rod, it may even be difficult to find the point where it made contact with the crankcase.

Strongly encourage y'all to purchase the Clymer and Haynes service manuals for your new-to-you Airhead. Read up on what chores you wish to accomplish prior to jumping in. These are basically very simple machines but you really want to avoid that Oh, S#*t moment when you discover a serious loss of $$$ and time.

Bob "Snowbum" Fleischer is a treasure of Airhead knowledge. His technical articles are extensive and detailed. They can also be used as a fast cure for insomnia.

http://bmwmotorcycletech.info/

From your photo, it appears someone in the dark past of your R65LS has used some sort of sealant when the pushrod tube grommets were installed. Clean out the remnants and do not repeat this error.

Welcome to the herd and our own little BMW asylum. We cannot offer a 12-step cure for the "addiction".

[mdecnsp]

Thanks for the info. We have bought the Clymer and probably will get the Haynes manual. I asked my son to find out more about how the engine lost all it's oil. I'm thinking that we're going to do a complete engine tear down since I'd hate to do only the top half only to find out that the bearings are bad later. We did a leak down test and the cylinders were leaking on the exhaust side.
The fuel tap being left on that Steve mentions could be the issue for the oil leak but there's no way to know. We'll ask about that.
Also, the brake master cylinder and calipers are completely frozen so those will need rebuilding.
The bike doesn't look bad at all. It's just been sitting for many years.
I'm very mechanically inclined as I have worked on cars all my life and did a complete frame off restoration of my 73 BMW 2002 tii so this will be fun.

[marcmax]

Oooo. BMW 2002. Definitely on my list of cars I lust after.