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Oil Pressure Switch

2wheeljunkie

New member
My oil pressure switch is leaking on my '72 R 75/5. I can get a switch from the USA, but it will take me awhile. I know the bike requires a M 10x1.0 tapered thread which doesn't require a crush washer, but am wondering if a M 10x1.0 thread that isn't tapered but has a crush washer, can be used?? I can get a fitting like that locally, and block out the external end with a plug, and just check my oil often until I get a new switch. The pressure switch is leaking enough that I don't want to leave it in and drive it, and it could turn into a gusher when I am miles from home.
Thanks.
 
There is a VW oil pressure switch that is the same from the older Bug, sorry I don't have the part #.

I have one on my R100GS.
 
This page has substitute parts...search for "oil pressure":

https://ibmwr.org/index.php/bmw-parts-substitutes

Early Airheads had the M10x1 but a bit later on they were M12x1.5. Snowbum mentions 3/8 NPT threads for early bikes. Make sure you get the right threads and make sure it switches on sufficiently to protect the engine.
 
This page has substitute parts...search for "oil pressure":

https://ibmwr.org/index.php/bmw-parts-substitutes

Early Airheads had the M10x1 but a bit later on they were M12x1.5. Snowbum mentions 3/8 NPT threads for early bikes. Make sure you get the right threads and make sure it switches on sufficiently to protect the engine.

I am planning on getting an original switch with the same threads, but have to order it from Boxer2Valve and it will take awhile, and I have some other things I am ordering also and I have them sent to Houlton, Maine as I live 60 miles from there and I can drive over and pick them up as it is much cheaper than mailing to Canada.

What I want to do now is put in a M10 x 1.0 with non-tapering threads into the hole, combined with a crush washer. From what I understand, this tapering starts towards the end of the hole and the part going into the hole starts tapering at the beginning so it only starts tapering as the bolt closes into the hole and the tapered threads pulls the fitting tight. A non-tapering fitting with a crush washer should do the same thing as the crush washer keeps the end of the fitting(bolt)away from the tapering threads and the crush washer does the tightening and sealing. The fitting I am looking at is a 1/8" NPT Female to M 10 x 1.0 male, and I could put a plug in the 1/8" NPT, or if I wanted I could set up another oil pressure sending unit to a gauge.
 
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