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Help with low oil pressurw switch location

kempfat

New Member
Joined
Sep 18, 2024
Messages
3
Location
North Carolina
Hello! I have a cat 239D SN:BL903499. I am having a really hard time locating the Oil Pressure sensor. Also, I heard that there may be a bulletin about faulty oil pumps. Can anyone tell me if that is for this machine? When I start the engine it runs great but after about 30 seconds or so, the low oil pressure warning comes on the screen so I shut it down. is this the sensor?1000009817.jpg
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
31,157
Location
G..G..G..Granville.........!! Fetch your cloth.
Despite the fact that the warning message refers to the oil pressure "sensor" it's actually a normally-closed switch that opens when rising engine oil pressure passes a certain value.

If for some reason the switch contacts do not open the software is programmed so that the Event only flags up after the engine has been running for at least 30 seconds.

The switch Part Number is 544-4080, location as per the illustration below on the cylinder head right behind the fan pulley. I can't find the specification anywhere. If you want to test for pressure at that point it appears as though the thread on the switch is 1/8" NPT.

1726675181905.png
 

kempfat

New Member
Joined
Sep 18, 2024
Messages
3
Location
North Carolina
Despite the fact that the warning message refers to the oil pressure "sensor" it's actually a normally-closed switch that opens when rising engine oil pressure passes a certain value.

If for some reason the switch contacts do not open the software is programmed so that the Event only flags up after the engine has been running for at least 30 seconds.

The switch Part Number is 544-4080, location as per the illustration below on the cylinder head right behind the fan pulley. I can't find the specification anywhere. If you want to test for pressure at that point it appears as though the thread on the switch is 1/8" NPT.

View attachment 321298
Thank you! I think the switch is bad. I have 62psi for oil pressure. The resistance is at 29ohms ... I think it's supposed to be .4ohms please let me know if I'm wrong. Thanks again!
 
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