R100R Mystic oil light stays on

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Kurt in S.A.
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Re: R100R Mystic oil light stays on

Post by Kurt in S.A. »

Your bike should have a rolled over lip on the canister and not the sharp edged canister that first showed up. If that's the case, then the use of the thin metal washer/shim might not be needed. This shim was ostensibly needed to prevent the o-ring from being cut.

Nice to hear that your o-ring is flattened to some degree...that means it was being compressed to some degree. Oak Okleshen wrote that having the o-ring squeezed by 10-25% was desired. The only way to know how much compression you're getting is to measure how much the canister is installed inside the case...what is the gap from the edge of the canister to the outside edge of the engine case? Once you know that, you can add up the dimensions of the o-ring (nominally 4mm), the metal shim (about 0.3mm), and the paper gasket (around 0.5mm) and do the math to see how much room that the o-ring is to be pushed into with various combinations.

Kurt
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SteveD
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Re: R100R Mystic oil light stays on

Post by SteveD »

Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Rob Frankham
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Re: R100R Mystic oil light stays on

Post by Rob Frankham »

The Mystic is a later machine and doesn't require the metal shim.

The paper gasket is only really necessary if you experience leaks to the open air.

The white 'O' ring will take up a flattened section with use, this is normal. You should always use a new ring.

There is no difference in usage between hinged and non hinged filters, either can be used as long as they are the right filter in the first place. Bikes with an oil cooler use a filter with an 'O' ring or seal at the inner end only. Bikes without use a filter with 'O' rings or seals at both ends. You are unlikely to get seals with speperate 'O' rings at the ends. New stock for decades has had fixed seals in their place.

I would strongly recommend that you only use OEM or Mahle fiters. Some aftermarket filters are known to collapse in use blocking oil flow. I woudn't trust them.

Rob
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Kurt in S.A.
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Re: R100R Mystic oil light stays on

Post by Kurt in S.A. »

Rob Frankham wrote: Fri Oct 14, 2022 12:56 pm The Mystic is a later machine and doesn't usually require the metal shim.
Fixed that for you! I would doubt there is absolute certainty with these bikes. IMO.

Kurt
justruss
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Re: R100R Mystic oil light stays on

Post by justruss »

learned all I need to know (and more) regarding oil filter installation - thanks kurt steve rob

one remaining question-where can (should) I get the crush washers for the
banjo bolts that screw into cover for oil cooler-they seem an unusual size
Kurt in S.A.
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Re: R100R Mystic oil light stays on

Post by Kurt in S.A. »

Where are you located? Read the section "The Basics" on Snowbum's site...plenty of other mentions of "banjo" on the page:

https://bmwmotorcycletech.info/Oil.htm

Maybe enough info to source them locally, at McMaster-Carr, or at a dealer.

Kurt
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gspd
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Re: R100R Mystic oil light stays on

Post by gspd »

justruss wrote: Fri Oct 14, 2022 2:49 pm learned all I need to know (and more) regarding oil filter installation - thanks kurt steve rob

one remaining question-where can (should) I get the crush washers for the
banjo bolts that screw into cover for oil cooler-they seem an unusual size
Any service place that does oil changes (like Jiffy Lube) or auto parts place should have a tray with an assortment of crush washers, I'm sure you'll find the right ones there.
Take an old one with you.
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justruss
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Re: R100R Mystic oil light stays on

Post by justruss »

changed oil & filter and reassembled everything

decided to take Snowbum's advice-
cranked engine without starting (removed plugs-good time to inspect anyways)
until oil light goes out - theory is oil circulates fills cooler etc

well oil went out and stayed out for what seemed too long
started engine oil light went out normally but again stayed out too long

seems the oil pressure sending switch is wonky-getting a new one
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gspd
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Re: R100R Mystic oil light stays on

Post by gspd »

justruss wrote: Fri Oct 14, 2022 5:28 pm well oil went out and stayed out for what seemed too long
started engine oil light went out normally but again stayed out too long
That's perfect!!
With a tight engine and thick cold oil the light may stay out for as long as 30-45 seconds before the system pressure drops low enough for the light to go back on.
The pressure has to drop from way over 100psi to below around 10psi for the light to go back on.
With a good engine, the residual oil pressure has to slowly bleed out the mains, and this can take a while.

Once hot, the thinner oil bleeds out almost immediately and the light will come back on right away.
Mechanic from Hell
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My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
justruss
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Re: R100R Mystic oil light stays on

Post by justruss »

ahhh-
makes sense - and not something I usually pay attention to
when it is chilly (or not) - start up - oil light out - don't normally shut right off
to see how long it takes to come back on
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