Oil pressure low, V1505. Over fill and aeration.

[aus4150]

Hello everyone, ive just gotten a 95 3 ton kubota digger and began servicing it, changing fluids and filters etc.
The wiring is trash so i installed an ebay panel meter with voltage, temp and oil pressure for the engine.
Anyway, finally got it out of the shed today and the oil pressure was 0 bar at idle, and only 1.4 bar at max rpm.
So i shut it down and tested the sender, it worked fine.
So a bit puzzled i installed a manual gauge on the oil pressure, again 0, shut it down and began to think.
After mudking around talking to diesel mech mates and googling i finally noticed a google AI suggeston that my engine may be overfilled, puzzled but intrigued i went further down this path.
Apparently over filling can resukt in crank/oil interaction which causes the oil to have too much air in it resulting in both difficulties scavenging oil and also forming pressure in the galleries.
So i checked my oil and sure enough now that the oil had gone a bit blacker frim just being replaced i could see i had over filled.
So i drained the oil out and recovered 8l, visibly frothy.
Poured 6l of new oil back in and started her up, straight away at idle i had 0.8bar.
Got the oil up to temp and it didnt drop back to 0bar, so good times.

 

[GeoHorn]

That’s a great illustration of why we should view the oil quantity specification as the MAXimum qty….not a minimum (as many view it.)

Thx for the confessi… err….the report.

 

[Trash Panda]

That’s a great illustration of why we should view the oil quantity specification as the MAXimum qty….not a minimum (as many view it.)

Thx for the confessi… err….the report.

Yep.

My L2501 gets 5 quarts on the oil change, not the 6 listed as “oil capacity” in the owners manual. Sits right in the happy medium that way.

 

[GeoHorn]

I have a (non tractor) engine…2 of them actually…which specify 8 qts. But if 8 are installed…within an hour of operation it has blown a quart out the breather and 7 will subsequently register on the “dip-stick”. If I install only 7 at an oil change….. it will remain there. (pressure stays at 50 psi and temps at 180F)