HELP: Oil Dummy Light Staying On Yanmar YM2000

[California]

Photo of my temporary-test oil gauge. I had this stuff already so it didn't cost anything. The brass fittings are, I think, from old gas lighting plumbing (Barn finds) including several brass short nipples. A couple of these threaded into the block properly and for others, the leading thread was too large to engage.

I figured these brass fittings wouldn't hurt the block despite the minor difference between US pipe thread and the British Standard pipe thread that Yanmar and most Japanese cars use. This temporary application sealed properly and didn't harm the threads in the block or on the brass pipe. Installing this temporarily verified that the sender had failed and there wasn't a problem with oil pressure.


Here's my old thread where I first posted the photo. The thread also documents my observations of normal temperature, measured at various points on the block and radiator.
http://www.tractorbynet.com/forums/yanmar/156109-low-oil-pressure-no-bad.html

 

[treedawg]

Photo of my temporary-test oil gauge. I had this stuff already so it didn't cost anything. The brass fittings are, I think, from old gas lighting plumbing (Barn finds) including several brass short nipples. A couple of these threaded into the block properly and for others, the leading thread was too large to engage.

I figured these brass fittings wouldn't hurt the block despite the minor difference between US pipe thread and the British Standard pipe thread that Yanmar and most Japanese cars use. This temporary application sealed properly and didn't harm the threads in the block or on the brass pipe. Installing this temporarily verified that the sender had failed and there wasn't a problem with oil pressure.


Here's my old thread where I first posted the photo. The thread also documents my observations of normal temperature, measured at various points on the block and radiator.
http://www.tractorbynet.com/forums/yanmar/156109-low-oil-pressure-no-bad.html

That looks great....

I've been busy lately and haven't done a whole lot on the Yanmar other than a quick look at the wires which failed to identify any problems.

td

 

[Electronics tech]

I recently replaced the damaged/missing dummy lights on my YM2000. I also replaced all of the sending units at the same time.

Everything has been going OAK for the last 4 weeks while planting a garden.

This evening I started it up and the oil light stayed on. I checked the oil level and it was fine.

I pulled a cultivator tonight and it remained on.

This tractor was well used/neglected by the previous owner and it smokes pretty heavy when first started then clears up. It also has some serious crankcase blowby so I was somewhat shocked that it wasn't staying on when I originally installed the lights.

I'm a little confused why it suddenly came on today....???

Help.....

I realize that this an old post, but for the sake of others who have the same problem, I am responding.

First, the oil light circuit on my YM2000 doesn't work like any of you have said it does. And it shouldn't, according to the diagram. When the ignition switch is turned on, 12 volts is applied to one side of the light. The other side is grounded through the normally closed contacts of the oil pressure sensor which is a simple pressure operated switch. When the engine is started and the oil pressure rises, these contacts are opened, extinguishing the light.

Therefore, a broken wire will not make the light stay on but off instead. If the sensor wire shorts to ground, the light will stay on until the short is removed or goes away.

Just what we need, more amateurs spreading disinformation to the unsuspecting public!

 

[California]

Just what we need, more amateurs spreading disinformation to the unsuspecting public! ...a broken wire will not make the light stay on but off instead.

Electronics tech: Yes, spreading misinformation is a problem.


Engine running - My light was on while the broken wire was dangling.

Touching the wire to ground extinguished the light.

Do you have a good tech explanation for this?

 

[ROUSTABOUT]

I dont have oil lights or gages on anything. I can't feel your pain.