re: 1992 R100RT Oil Pressure Light

[beemerbob1]

re: 1992 R100RT Oil Pressure Light

Hey all, Situation is this: recently changed oil. Ran bike fine. No oil light on. Decided to have a few items powder coated so I removed them while recovering from carpal tunnel surgery. While it was down, I took to shop to have splines lubes as there are 63,000 on bike and I am pretty sure they have never been done. got the bike back and all parts installed. Started bike and oil light is on. Texted mechanic as to why light could be on. He thinks it may be oil pressure switch. Changed out switch. tested old one, it is still good. Started engine and light is still on steady, no flicker. I really miss riding!! Suggestions????

 

[20774]

Welcome to the forum! I'm assuming you're talking about lubing the transmission input splines, right? So the bike, less the parts that were being powder coated, was taken to the dealer for the spline lube. They likely removed the transmission in order to clean/lube the spines. Probably a good thing to question the pressure switch as they had to disconnect the wiring to pull the transmission. But it sounds like it's not the switch as you replaced with a new one.

Can you double check to be sure it's the oil pressure light on the speedo pod? Sometimes it can be confused with the alternator charge light.

If truly there is a loss of oil pressure, running the engine too much can be dangerous. You may need to measure the oil pressure at the switch location to confirm. The threads for the switch should be M12 x 1.5.

 

[beemerbob1]

Thanks, yes he pulled tranny to lube those splines. it is definitely the oil light. No, I will not be riding it while that light is on.

 

[20774]

Thanks for the update. There are other things that could cause loss of oil pressure, but they're are pretty unlikely to happen. Sounds like you need to get a pressure reading to identify if you truly have an oil pressure problem. Could the mechanic do that for you?

 

[beemerbob1]

I am sure that he can. I will get with him tomorrow as it is Sunday. I am also wondering IF there is an off chance that I messed up when I changed the oil filter, but is is weird because I rode it for a while before taking it to the shop for the lube.

 

[20774]

Ah...I didn't realize you changed the oil filter. I would definitely bite the bullet and revisit that. On the newer filter set up, there's a minimum of a large while o-ring...assuming you don't have an oil cooler. Sometimes there's a large thin spacer that goes in before the o-ring. Could be that the o-ring is not properly seated.

 

[52184]

Some time spent reading on Anton’s site may be worthwhile to the OP.

http://largiader.com/tech/filters/

http://largiader.com/tech/filters/canister.html

Also, once the filter status has been verified it would be a good idea to remove the pressure switch and connect an oil pressure gauge in that port, just to verify that all is working. One can also turn off the fuel taps, drain the float bowls, and with the rocker covers removed crank the engine to see if oil is reaching the rocker shafts via the passages feeding the top of each rocker shaft.

And, it’s possible a wire got pinched during the R&R of the trans, so that’s worth checking, too.

Best,
DeVern

 

[beemerbob1]

WOW, I feel like an idiot.

After looking closer to the gauge pack, I realized that it IS indeed the "Gen" light that is on. I replaced the starter while the bike was apart for powder coating and I am second guessing that I replaced the connections at the solenoid. Will that leave the light on? When I hit the button, it kicks over without a hitch.

Some time spent reading on Anton’s site may be worthwhile to the OP.

http://largiader.com/tech/filters/

http://largiader.com/tech/filters/canister.html

Also, once the filter status has been verified it would be a good idea to remove the pressure switch and connect an oil pressure gauge in that port, just to verify that all is working. One can also turn off the fuel taps, drain the float bowls, and with the rocker covers removed crank the engine to see if oil is reaching the rocker shafts via the passages feeding the top of each rocker shaft.

And, it’s possible a wire got pinched during the R&R of the trans, so that’s worth checking, too.

Best,
DeVern

 

[20774]

Well, you're not the first nor the last!! The charge light is a measure of the difference in voltage between the alternator output and the battery. If both sides of the bulb have 12v, then no current flows and the light is out. If only one side of the bulb shows 12v, then current will flow. So, if one side of the bulb is connected to the battery and the other side isn't connected to the diode board, then it surely seems like the light would be lit.

 

[beemerbob1]

So, would it be a connection at one of the starter leads?

 

[20774]

Not sure what you're asking. The connections at the starter are power from the battery, a connection from the starter relay, and a connection to the diode board (B+30). One side of the charge light goes to the diode board at D+.