Oil Filter Sealing O-Ring

[JLThomas]

I know the $2000 oil-ring has been covered here before, but please bear with me a minute.

I've been the victim of this c**k-up, after incorrectly fitting it after an oil change. The result was a melted crankshaft shell. I've purchased a 2nd hand short engine, and I'm refitting it at the moment.

My question is this: I've measured the gap from the inner oil 'tube' to the surface of the engine, fitted the shim and ring to match, but how do I know I haven't shredded the o ring when I put it back together? It's like the 'does the fridge light really turn off when you shut the door?' question. Is there a way of checking the oil circulation (which this o ring, or lack of, will control) without removing the oil filter cover?

I reckon I've got another week's work (at least) before I get near to trying to start the engine, but I'd love to have some way of building up my confidence that I'm not going to end up with more grilled cheese inside my new engine.

It's a 1981 R65, and the old engine had just topped 75K miles. The replacement engine block is from 1983, and has done 53K.

Thanks, in anticipation.

[airhead]

The O ring shouldn't 'shred' if it's installed correctly, that is, between the cover lid and shim. So the sequence is, cover, o ring, shim, the O ring is sandwiched between the cover and shim. If you've been putting the shim onto the cover first, then there is nothing to contain the O ring when it bears against the edge of the filter tube and can be displaced/shredded like you fear.

Also, are you sure the replacement engine needs the shim? Around '83 - '84 (I think, but no -one has been able to give me a definitive), they got a swaged tube that wouldn't leak back into the sump causing a loss of oil pressure.

Bill....................;-)

[Justin B.]

You may want to read up on everything oiling system related on this site:

http://bmwmotorcycletech.info/techindex.htm

From my understanding, if you sufficiently damage the O-ring then it allows pressure to bleed past the "can", back into the crankcase, resulting in low or almost no oil pressure.  I would think the oil light would come on.

As far as knowing if you have it right, it's kind of a faith thing.  Clean everything up, slip in shim, white O-ring, then cover.  I always put some nice sticky grease on the shim and O-ring to keep them in place when I'm fiddling the rest of the stuff on.  Snowbum also has an article to allow you to determine if you need the cover gasket as well.  I don't run a gasket on any of our R65s or R100s...

[MrRiden]

I've laid in quite the supply of O rings and experimented with them to find a combo that provided a nice amount of squish [cover, ring, 1 metal shim, no paper] on my bike. There was a fellow who had made up an excel spreadsheet where you plugged in your measurement and it kicked out the right combo. You may find it by posting over on the BMWMOA site. Another [expensive] option that has me intrigued can be found here http://www.bmwboxersupplies.com/product_info.php/cPath/1/products_id/182
rich

[Justin B.]

Is that the one made by Motoren Israel?  

http://www.motoren-israel.com/product_info.php?info=p16_Spezialoelwannenzwischenring-25-mm-mit-Au-enfilter.html

I looked into that for my RT a few years back due the PITA of changing the stock oil filter with the fairing in place...

[JLThomas]

Thanks for all that. I have read through everything I can find, and I had made sure that I had everything in the right order. I think It must have just slipped out of place as it was going on, and then gotten squashed. For  the new engine, I haven't seen anything that says it needs anything different to the '81. I've measured the gap using some simple formulae that someone (Snowbum?) put up, and that showed that I needed shim, but no gasket. I think I might even need 2 shims.

I'm hoping that the oil light will give me some warning if there is a problem, but I don't recall it lighting up before the meltdown.

If I get it going (if!!!) and do a few miles just to get it warmed, where's the best place to check for oil having been distributed correctly?

Thanks again for your help.

[Bob_Roller]

Without an oil pressure gauge installed , I don't know there if there is any way to tell if you have a problem , until it's too late.

There is enough oil pressure to extinguish the oil pressure light, but I think it only requires 3 psi of pressure to do that.

But not enough pressue to protect the vital bearing surfaces inside the engine.

[donbmw]

I and a friend were going on a trip he had changed his oil the day before. When he started his bike a R100RT 1982. He saw that the oil press light did not go out. We found that he had forgotten to put the shim on when he installed the oil filter cover. Found the shim were he dump the oil. Reinstalled shim and everthing work fine for the few year he had the bike. So hopefully you would not get the oil light to go out when starting the enging.

Don

[Justin B.]

Sitting at idle for a couple of minutes might be OK, you can always pull a valve cover and if you get oil squirting it's a fair bet you have some oil pressure.  I become more and more tempted to install oil pressure gauges on my daily riders...

[Bob_Roller]

Has BMW put an oil pressure indicator on any of the  airheads ?

I have searched the parts manuals, and the only additional igauges I can find are for a voltmeter and a clock.

Has anyone done any research for parts for an oil pressure gauge  for our bikes ?

Giving this just a little thought, if you could find a manifold that would thread into the existing oil pressure switch hole, then install a pressure sending unit, and possibly the stock low oil pressure switch , so the 'idiot' light stills works, to get your attention if you happen to miss the indication on the gauge.

[Justin B.]

It would be fairly easy to plumb in a "tee" to suport the light switch and a connection for a mechanical oil pressure gauge...  Space would become more of an issue with the sender required for an electrical gauge.

[airhead]

I have this setup for the oil pressure sender on my 90/6, and the clearances for the sender is fine as it just clears the carb with mm to spare. However, as the 65's stroke is shorter, I recon the clearances would be much closer though I haven't tried it and it might need a remote tube up of the sender from the T connection, attaching it to a bracket somewhere on the frame.
If you want some more info on oil pressure and temperature gauges on Airheads, try this download .pdf file;

http://www.mediafire.com/?fmz2mg2gl3z




Bill......................;-)

[MrRiden]

Clearest most concise info I've found on th O ring installation with photos and diagrams. Gets right to the point unlike some other verbose nonsense this is worth saving.
rich
http://www.largiader.com/tech/filters/
http://www.largiader.com/tech/filters/canister.html

[JLThomas]

MrRiden - thanks for the links, by far the clearest and most concise explanation I've seen.

The new engine is now back in the frame, but I haven't connected up the exhausts, battery or tank yet, so I'll re-open the oil filter and check the dimensions again. I'm sure when I checked it that it was 4mm from engine surface to canister lip, and from Snowbum's instructions I went for shim (I had to do this anyway, as the canister isn't lipped), but no gasket. From the details on largiader.com I think I may be fitting an extra shim.

I'll let you know how it goes.

[MrRiden]

Bill,
Thanks for the photo of the T fitting. Does anyone have a recommendation for a quality oil pressure gauge. The units at my local auto parts place all require plumbing. Are there any that use an electrical transducer? I think that might be the way to go. If not, perhaps a gauge mounted low on the engine somehow? I'm thinking I'd really like to add one if it can be done cleanly!
rich