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Just curious if anyone has a long term solution to the oil pressure switch leaking problem. This is the 3rd switch I'll need to replace in 10 years.

To be specific, we are not talking about the gasket/threaded portion leaking - I'm talking about the switch itself.

BTW - Silicone goop doesn't qualify.

thanks

I put in the aftermarket switch from Motobins. 5 years - no leaks.

It's kind of dim in my memory, but I think Tom Cutter has mentioned on the Airheads list that he uses something like a JBWeld product to but a barrier around the exposed part to keep them from leaking...have to leave the terminals exposed. He might have also been talking about the neutral switch.

I installed OEM oil pressure and neutral switches in the past couple of years straight from the box. Not a leak. I do remember they can't be torqued very much otherwise they twist and likely crack the internal potting material...tighten just enough to crush the washers.

Kurt in S.A.

Ray from Indiana wrote:Just curious if anyone has a long term solution to the oil pressure switch leaking problem. This is the 3rd switch I'll need to replace in 10 years.

To be specific, we are not talking about the gasket/threaded portion leaking - I'm talking about the switch itself.

BTW - Silicone goop doesn't qualify.

thanks

hi ray, clean the switch base with prepsol and use some slow curing araldite pour around the base of the terminals until it starts to pool up and it should fix the problem , the area that your sealing must be very clean though !

Thanks for the tip. I don't know the term araldite. Is that a slow cure epoxy resin? I'm assuming so

I'll try this to see how it works

sorry mate, should have told you its expoxy, its very strong have used this stuff for years on fridges etc ( alloy to copper etc ), just make sure it has cured properly , perferably somewhere warm , if the packet says cured in 48hours leave it again for days before you fit the new switch. you can get 5 minute araldite but this will cure to fast, try to purchase the slowest one if possible to let it soak into the joins etc.

Ray I don't recall you mentioned your bike, but assuming it's like at least one of mine...I wonder if you are not kicking the switch somehow. Mine have shown leakage after 25/18 years, but not soomer. I think the neutral switch on the '78 R100s was the OEM switch...I replaced it in 2006. That's a long time...
I did kick the end of the OP switch and that started it leaking. (Note to Ken: OP is oil pressure)

It's an 82 R100. I don't think I'm tapping the switch with my toe but I'll be consciously aware of that in the future. More likely I'm probably tightening too tight and causing the leakers as Kurt offered.

The JBWeld or epoxy potting doesn't sound bad either. I'll do the shotgun approach with all three suggestions and see how long the replacement lasts without weeping...I hate oil leaks. Did I ever mention I used to run BSAs-you get the picture.

The epoxy thing might be a good idea for the neutral switch due to it's difficult access. They do last a very long time usually, so maybe it's the thing that gets changed over when the trans is out. They're not expensive.

I've had the oil pressure switch leak on me on a long ride. It was close to 80K km old. In 200kms it almost lost enough oil to get to the MIN mark on the dipstick. Some of that made it to the rear tyre and then the roads became wet! Next time I travel on a long trip, there'll be a spare under the seat. Maybe a short term blanking bolt could be an idea? What size is the thread? Anyone know?
When I replaced the switch, I did it up snug. I watched it for a while to check for a leak due to "not tight enough" which was the case. A further careful tweak stopped the slight leak.
Click to enlarge.

Steve
The thread for later airheads with non-tapered thread is M12 x 1.5 I guess a blanking bolt and crush washer would work if one had a bad leak on the road. ( Do you feel lucky? )