oil pressure light intermittent

[KevinMolyneux]

I have a 1980 GS850. Last year the oil pressure light started coming on dimly from 2000 to 4000 rpm. It has since started coming on more often and occasionally stays on. I've done oil changes without effect. I've not seen any overheating or smoking. The engine seems to run just as well as ever. There are only 35,000 miles on the bike.
How can I check if I have an oil pump problem or a sending switch problem?
Thanks Kevin M. Long Beach CA

[focus frenzy]

back behind the cylinders below the doohicky sticking out and under the carbs is a white plastic knob with a wire attached to it. this is the oil FLOW switch. follow that wire and make sure it is not rubbing on anything as a short in this wire makes the light come on.

the clutch cable can rub and wear a spot in the wire and also in the plastic jacket around the clutch cable, and cause a intermitant short that will only get worse with time.

[rustybronco]

does you bike have an add on, oil cooler?

[BassCliff]

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[KevinMolyneux]

No oil cooler on the bike
Thanks
Kevin

[Tarbash 27]

Hook up an oil pressure gauge to the right side of the motor. There's an oil galley plug there. That will tell you if you have an oil pressure problem. Ask Renobruce about a gauge if you dont have one. If thats not your problem. Probably the switch is bad or a wiring problem.

[bwringer]

These roller bearing engines don't really generate much pressure at all -- it was correctly referred to as an oil FLOW switch earlier. An oil pressure switch generally causes unneeded panic when it drops to near zero on a perfectly running engine. They pump lots of oil around, but the passages are wide open and generate very little pressure.

An electrical issue is far more likely. The connector on the oil flow switch is very weak and exposed, and the wire runs past all sorts of potential rub points.

[BigLou]

glad I found this thread, this sounds almost exactly like what my GK started doing today.

I was about 2 hours from home, came off the interstate and as I slowed down the oil light started to flicker. when I came to a stop it stayed on. I checked that oil level, it was fine. So I started out again, and as long as I was accelerating or running steady, it stayed off.

Now the tricky part, some times when I would decel, it would stay off, the next time it might come on.

Does this too sound like a wiring issue or something more serious?

Thanks

Lou

Yes I will go check the wiring, but I wanted some confirmation first if possible.

[chef1366]

Those lights are there for a reason. Check oil flow first.

[BigLou]

im not the most mechincally adept guy, how would i check the oil flow?

[chef1366]

Look for Renobruce and get a oil pressure guage

[Nessism]

On the 8V GS engines the oil pressure switch is a spring loaded metal plunger that sits down over top of the main oil port in the engine. When the engine is started and oil flows, the metal plunger is pushed out of the way which disrupts the oil lights ground circuit.

To check the wiring for the oil light system, remove the wire from the top of the pressure switch and ground the wire, the oil light should come on and not flicker. The system is very simple and reliable. The pressure switches almost never go bad.

I suggest checking wiring first since that's easy to check. If the wires function correctly, check flow as suggested using a gauge of some sort in the engine port.

[BigLou]

Thanks all!

great news, the wire that goes the switch was just laying on the case, so when the vibes weer right it would make contact otherwise, it was on top of a hose and would not.

Problem solved, now all i have to do is figure out where it is supposed to be hooked up. LOL

GSR is great

[BigLou]

Ok, now for the stupid question of the day. Where the hell do I hook this wire up to? Ive looked on BassCliff's website at the manual no dice.

Anyone happen to have a pic of what is wire it to be connected too?

Thanks again all.

[posplayr]

There is a brass contact like a "head of a nail" on top of the oil cover right under your carbs. Slip the connector onto the head of the nail.

Pos