Oil & Fuel Oil Light

[airbear]

Older Kubota L175 1500 hrs. starts easy, runs smooth
Oil light on, start engine, oil light off, 45 seconds, oil light back on at any rev. ???
Decided to remove oil pan and do visual, removed all obvious bolts , pan stuck ??, tried bumping, tried prying with screw drive in joint & lite taps, Seem stuck solid or something I missed???

Suggestions/ ideas, much appreciated
thanks
aiarbear

 

[flyerdan]

It was probably glued on with permatex or something similar sometimes the bond is almost too good. I assume you checked for correct oil level first, maybe take the sender for the light out and put in a fitting and test with an analog gauge to see if there is actual pressure.
What I would suspect is that there is a pin hole in the rubber diaphragm in the sending unit that allows the pressure to equalize and the light to come on after a bit.

 

[airbear]

Great ideas. Do you happen to know the location for the sending unit? At this point, I will force a wedge between the oil pan and block if the sending unit is inside the pan. Man , appreciate the analysis of the problem.

 

[flyerdan]

The sending unit will be on the side of the block, probably above the starter. It will look like this, with a wire going to it. How it works: it's a normally closed switch that completes the ground circuit to the oil light. When pressure is applied, about 5-7 psi it opens the switch and the light goes out. If there is a breach in the rubber diaphragm, the pressure will equalize and the switch will close again.
If you take it out and test with a gauge, be advised that some Kubota engines use BSP pipe threads instead of NPT. Thee is only 1 thread difference in pitch, but it can bugger things up enough to cause problems. There are a couple threads detailing this in the similar threads box below.

 

[airbear]

Hey flyerdan, many thanks, spot on solution. Change pressure sensing unit , problem gone. I was dreading an in depth tear down. $13.00 part at Kumar Bros, free freight.

 

[flyerdan]

Glad it was a simple and inexpensive fix, those are the best kind. From the symptoms you described I was pretty sure that was it.