Oil pressure/level issue...

I've been having a problem with the oil light on my '82 XJ1100J.
The light often comes on not long after first starting it (from cold). It will stay of for 15 seconds to a minute or so then go back off. Some times it goes through this cycle several times. In almost every case after 10-15 minutes (once it's all warmed up) it stops doing it and I won't have any more issues with it all day.
The oil level is actually above the high line...yes it's measured on the center stand, level, and a dew minutes after having been run and all that. It's usually right at the top of the sight glass.
It seems to do this more if the oil gets low...but low is still well into the middle of the sight glass marks.
It's like the sensor is at the wrong height or something.
It's getting old...51K, but It's had this problem for years...probably 10-15K miles at least...so I doubt it's actually starving for oil.
Any ideas??

 

Might have to remove the sensor from the oil pan (which usually means dropping the exhaust to get to it) and then soaking it in mineral spirits for a few hours/overnight, blowing it out with (minimal) air pressure, re-soaking it, etc. There is basically a "float" inside the can that, well, "floats" as it fills up to the oil level in the sump. Lots of years and sludgy oil can make it stick or be sluggish in its movement.......

 

Hum... That's possible....but the behavior I see seems a little too repeatable for a "sticky" float. Seems like something like that would stick sometimes and not other times.
This only happens at startup (from cold) and does it a 1-4 times and the I won't see it the rest of the day.
I guess the sticktion could go away once it warms up...that would make sense.

 

Mike, listen to what Len said. Try it. It wouldn't be the first time I've come across that, too, with that being the culprit.

Remember, the sensor is sitting right down there in the pan where all the muck settles. (What muck, doesn't the filter get it all?) NO....it doesn't... That's why there's a thin layer of 'mud' in the pan when we take the pans off. Yes, the filter gets almost all of it, but there IS that little bit that stays in suspension at the bottom.

Now, compound that over a 30 year lifespan and realize that if the oil is going into the sensor, there is a portion of the 'mud' that is washing in, too. Not all of it will wash out, so residual amounts will remain. Over the 30 years or so, enough can build up to make it sticky.

I sure as heck would rather flush it out and find that was the problem, rather than assume that since it "goes away", everything is really fine......only to find out that it was something else causing an oil starving issue, and the sensor was trying to tell you THAT>>>>

Dave F

 

Good points on the muck. I had the pan off several years ago while fixing third gear not to mention a ton of other engines so I get that.
I even have a gasket laying around for it in the garage too.
And you're right, it can't hurt.
It is an oil level sensor that makes the light come on....not an oil pressure sensor right??

 

I meant second gear....

 

Yes, it's an oil LEVEL sensor, not an oil pressure sensor. No oil pressure sensors on these engines, Yamaha had great faith in their oil pumps and engine bearings............

Of course, it could be a loose wire within the sensor or somewhere else, but that would not really account for the behavior you observe.

 

I would agree with Chacal. When the engine is cold the oil is thicker and sticking would be more likely than when the oil is hot not to mention vibration of a running engine.

 

Thanks all!