What does "oil - low pressure" light mean when it just barely starts coming on?

   / What does "oil - low pressure" light mean when it just barely starts coming on? #1  

jpilk99

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I'm out there brush-hogging and noticing, after 10-15 mins that the oil - low pressure light on my odometer is flickering/glowing coming on when really under load and then goes off when rpms climb back up. I checked oil level before use and it was good. Any thoughts? Normal??

Thank you,

Jay
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #2  

/pine

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I'd check the wire on the sensor...
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #3  

Eagle1

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on my old truck it means I'm a quart and half low if it flickers up hill. :cool:
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #4  

Raul-02

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after 10-15 mins that the oil - low pressure light on my odometer is flickering/glowing coming on when really under load and then goes off when rpms climb back up
Ummm check your oil.
Just do that and, don't overthink it.
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #5  

JimRB

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One of my cars like 20w50 oil. Oil light would come on with thinner oils. Note that it is a pressure switch, not an oil level switch.

I had an oil light come on in my Toyota. Turned off engine and got a tow back home. New oil pressure sending unit fixed that problem.
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #6  

Eagle1

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Yeah but if my truck is low on oil the pressure varies. YMMV
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #7  

Hay Dude

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I'm out there brush-hogging and noticing, after 10-15 mins that the oil - low pressure light on my odometer is flickering/glowing coming on when really under load and then goes off when rpms climb back up. I checked oil level before use and it was good. Any thoughts? Normal??

Thank you,

Jay
Are you on hills? Sometimes that can make warning lights come on.
I could see where REALLY under load could make a oil pressure light flicker- like close to stalling.
 
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   / What does "oil - low pressure" light mean when it just barely starts coming on? #8  

JC-jetro

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several things could cause it.
1- Your oil sender unit is defective or close being defective. Sender is a normally closed switch by action of an internal spring. Upon start up, it maintains a closed circuit hence oil light pressure illuminating. As soon as pump start pumping oil, then the oil pressure will opens the switch and then oil pressure light will go out indicating pressure. Now this is for only "idiot light". The sender could also have a variable resistor, calibrated to digital or analog(needle) that actually shows pressure. This one is more preferable but mainly used on some automobiles more so than tractors.

2- If your oil level is low and you are in an incline (up or down) then you oil pick up tube and screen might suck some air while pumping, causing the pump to cavitate a bit, not making pressure and illuminating the low pressure light. A partially clogged screen can cause that and to clean that engine pan needs to be removed.

3- There is a very low possibility that your gear driven oil pump is damaged or has some restriction. This is very seldom a root cause but there is a possibility.

4- Check for loose wiring at the sending unit and also check all the fuses. Also check the connection at the back of tachometer.


By the way, I had to change my oil sending unit once 15 years ago. It was stuck closed.
 
   / What does "oil - low pressure" light mean when it just barely starts coming on? #9  

Doughknob

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How old is your oil?
 
 
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