Oil pressure switch leaking oil...tank off job?

Bikermike1411

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Hi everyone.

I'm on holiday in the highlands, did a cracking 300 mile loop today, stopped for a photo and noticed oil burned onto the Exhaust Y piece at the left hand side.

Shiiiiiiiit.

Limped 30 miles back to the campsite checking it every 5 miles. That took two hours....then I set to work.

I did the oil two days ago, and thought it could be either the sump plug or the filter. Tracing it back it was dripping from a bolt at the lower-rear of the LH cylinder, and around the LH cam chain tensioner bolt, up the side of the crankcase, on top of the crank cases....

By now I'm thinking it's nothing I've done....

Working logically down from the oil cooler nothing seemed amiss, until I reached the crank case again, and noticed fresh oil around the crush washer on the pressure switch. Wiped it clean, started the bike....and more oil. Just a weep, but enough that it'd pool on the crankcase on a long ride, then run off to the LHS as a big drop when it got enough.

I hope....

Anyway. I'm hoping it just needs nipping up. Ive sourced some Ptfe tape as well, in case it needs any more sealing, but the 'but' on the switch itself is much bigger than BMW factored into their tool kit! Does anyone know what size it is, assuming it's a standard BMW one?

I don't want to get RAC'd home!


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Oh yeah.... Is it a tank off job, or should I be able to get it just with the side panel off?

It looks a squeeze in there....


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First off........

The oil pressure switch is located on the left hand side of the crank casing below the left hand cylinder head. Just up and rear of the oil sight glass.

The oil temperature sensor sits on the oil manifold, on the right hand side above the right hand cylinder head.

Therefore....

I think you are referring to the oil temperature sensor.

Proceed as you see fit. Personally if the leak is not to bad, I would live with it until you get home. A little bit of oil always goes along way and looks like a lot more than it actually is. It sounds like the crush washer has corroded.

It's a 19mm nut on the sensor, it's not a job I have tackled, but it looks like even with the tank off it could be awkward.

I would be surprised if the RAC man didn't have a crush washer, and the tools to fix it by the roadside

Good luck.
Ian
 
If it's on the left (i.e. nearside) I'd be checking cam chain tensioner bolt, oil pressure switch and oil pipe banjo union in that order. I had a similar problem with slight oil weep. Turned out tensioner bolt wanted snicking up a bit. Doesn't require tank removal. Hope it didn't spoil the "loop" too much.
 
You're right Ian, top of the crankcase on the RHS. I did consider corrosion, but I thought it may have been the crankcase itself where the washer seats.

I'll have a look this morning and suss the job out.


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If it's on the left (i.e. nearside) I'd be checking cam chain tensioner bolt, oil pressure switch and oil pipe banjo union in that order. I had a similar problem with slight oil weep. Turned out tensioner bolt wanted snicking up a bit. Doesn't require tank removal. Hope it didn't spoil the "loop" too much.

Cheers West Coast. The loop was awesome (I'll stick a report up with pics when I get home)!


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Did you have the rocker cover off?

If so it's the sparkplug tunnel seal

Otherwise the oil pressure switch I'd the big hex nut just forward and below the left cylinder it has one wire to it If they leak it's "Usually just a small weep but gets blown backwards by the airflow

Neither need the tank off to sort
 
Did you have the rocker cover off?

If so it's the sparkplug tunnel seal

Otherwise the oil pressure switch I'd the big hex nut just forward and below the left cylinder it has one wire to it If they leak it's "Usually just a small weep but gets blown backwards by the airflow

Neither need the tank off to sort

Neither one Doc!

I'm pretty sure it's the oil temp sensor - top of the crankcase on the RHS, behind the side panel. That's the highest wet point I can trace oil back to.

Looks a right sod to access to check/tighten it though.


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Neither one Doc!

I'm pretty sure it's the oil temp sensor - top of the crankcase on the RHS, behind the side panel. That's the highest wet point I can trace oil back to.

Looks a right sod to access to check/tighten it though.


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You do get corrosion there and not to difficult to sort. Also can loosen if tensioning alternator with a screwdriver from that side. Tank off job (couple of minutes if GS with quick release couplings). If you need a hand, let me know and I'll pop over.
 
You do get corrosion there and not to difficult to sort. Also can loosen if tensioning alternator with a screwdriver from that side. Tank off job (couple of minutes if GS with quick release couplings). If you need a hand, let me know and I'll pop over.

Mines pre quick release... Need to source two 8mm bolts to bung up the fuel lines...just checking where I can 'borrow' them from on the bike!

Are you far from Roy Bridge mate?


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Ah I confused you with west coast traveller just then, I thought your oil was down the left side

Okay it is a tank off job You will need an 18mm alloy ring seal (same as the final drive plugs)

There is an Oil return from the oil cooler which you need to remove (Careful you do not lose the O ring ) LINK. a long Wobble fit, allen socket key makes these sooooo much easier to get out (5mm again If I remember correctly)

You cannot unscrew the sensor (unless you have a Looooong Socket with a slot cut out for the wire) if you do not have that out of the way! Believe me I have tried

There is an alloy washer on the temp sensor it corrodes away and leaves you with a small leak that after a while gets messy
 
Ah I confused you with west coast traveller just then, I thought your oil was down the left side

Okay it is a tank off job You will need a 16mm alloy ring seal (like the sump drains, but Please Check before you start !!!)

There is an Oil return from the oil cooler whech you need to remove. a long Wobble fit, allen socket key makes these sooooo much easier to get out (5mm again If I remember correctly)

You cannot unscrew the sensor (unless you have a Looooong Socket with a slot cut out for the wire) if you do not have that out of the way! Believe me I have tried

There is an alloy washer on the temp sensor it corrodes away and leaves you with a small leak that after a while gets messy

Have I got this right....

I need to unbolt the oil return pipe next to the temp sensor to gain access to the temp sensor to tighten it with a spanner?

How much oil am I going to lose when I take it off....? I'm hoping oil cooler drained back into the sump!


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And if there's nowhere I can get a washer, can I just nip it a little tighter, or clean up/rotate the washer slightly?

Plan B is limp home checking it at every service station.....


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And if there's nowhere I can get a washer, can I just nip it a little tighter, or clean up/rotate the washer slightly?

Plan B is limp home checking it at every service station.....


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I think if I needed to get back home today I would try to get as far as I could as long as the oil isn't pishing out. Hard to say without seeing how much is being lost. If need be top up the oil as you go along but keep an eye on how much oil is getting onto the y piece. You'll get home quicker from Glasgow/Stirling by RAC than from Fort William. Unfortunately the nearest bike shop is in the opposite direction to where you want to be. Alternatively there are BMW Motorad in the Glasgow are who might have the washer and could fix it for you. There is a large repair garage on the A85 near the junction with the A827 (Falls of Dochart road) if that's any help.
 
Right... I've done the job! Tank off was the hardest part.... Thankfully I brought my Teng 1/4" set and 'Bits box' - it has a tiny hex bit ratchet spanner in, and is invaluable for getting in tight spaces.... Cracked the oil cooler line no probs. I borrowed a 19mm spanner and nipped the sensor up about just a bit more than 16th of a turn. Put it all back together and now have it running to check for leaks. It's up to 4 bars on the temp sensor and no issues yet......


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Got back to Lancs fine - 335 miles from Roy Bridge with two stops for fuel. Actually about four stops between the campsite and Dalwhinnie to check for leaks, then just for fuel after that. 1050 miles door-to-door over the trip.

Truth be told, the oil issue didn't actually alter what was actually an absolutely cracking weekend away! I can't believe I didn't buy a GS years ago....

Thanks again for all the advice guys, WCT and the Doc particularly. I owe you both a beer! You can resume the piss taking now..... ;)


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Glad you got back ok, albeit a bit delayed. Only decision now is whether "to replace or not to replace" the alloy washer..............But if that's the only problem sounds like the bike's sorted.
 
Glad you got it sorted.
Have a look at post 12 of this thread for a pic of the offending area.
http://www.ukgser.com/forums/showth...ult-code-277?p=4186570&viewfull=1#post4186570

It's quite common apparently.
I was hunting down a fault when I noticed mine like this.
Spent a bit of time cleaning up the corrosion and refinishing the area. New crush washer which is a few pence from BMW, cheap open ended spanners to remove the oil switch itself and was grand for many miles after.
 


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