Oil Spewing out of Crankcase Breather

   / Oil Spewing out of Crankcase Breather #12  
I did note the my pressure gauge was in the 2.0 range.
Actually, I think you misplaced a decimal. That's probably 0.2 MPa. Anyway, there's nothing wrong with that. In case you didn't do the conversion, that equates to 29 psi. And assuming your OPSU is properly calibrated, an indicated pressure all the way down to 0.05 (at warm idle) is acceptable as well. That's still >7 psi.

Do you know how to calibrate the OPSU?

//greg//
 
   / Oil Spewing out of Crankcase Breather #13  
Actually, I think you misplaced a decimal. That's probably 0.2 MPa. Anyway, there's nothing wrong with that. In case you didn't do the conversion, that equates to 29 psi. And assuming your OPSU is properly calibrated, an indicated pressure all the way down to 0.05 (at warm idle) is acceptable as well. That's still >7 psi.

Do you know how to calibrate the OPSU?

//greg//

Actually he read the gauge right,:D but forgot that the guage has a multiplier of X 0.1 MPa. shown on it. Either way its .2 MPa. Just a technicality:D

Dave
 
   / Oil Spewing out of Crankcase Breather
  • Thread Starter
#14  
Thank you for the information Greg, and no I'm sorry I don't know how to calibrate the gauge. Can you please direct me to any instructions on how to calibrate the pressure gauge?

Thank you,

Peter
 
   / Oil Spewing out of Crankcase Breather #15  
Sure. This assumes you still have the OE sender and gauge. This procedure should be performed on a cold engine.
1. Loosen the jam nut behind the oil pressure sending unit to the point where you can rotate the OPSU by hand.
2. Turn the keyswitch to ON (don't start engine)
3. Make sure there's plenty of slack in the OPSU electrical wire
4. Rotate OPSU right or left while watching oil pressure gauge
5. Find OPSU location where gauge needle points exactly to zero
6. Turn keyswitch to OFF
7. Tighten OPSU jam nut
8. Reposition OPSU electrical wire to your satisfaction

//greg//
 
   / Oil Spewing out of Crankcase Breather #16  
sounds like a broken ring, and blow-by into the case
 
   / Oil Spewing out of Crankcase Breather #17  
sounds like a broken piston ring, check compression on cylindrs
 
   / Oil Spewing out of Crankcase Breather #18  
The metal mesh material was removed and it is clean except for some oil residual as a result of it spitting through.




Just a general comment; If the gasket between the crank case filter assy and the side of the block was or is install wrong will not allow engine oil to return to the pan and back up through the mesh.


Ronald
Ranch Hand Supply
 
   / Oil Spewing out of Crankcase Breather #19  
Sure. This assumes you still have the OE sender and gauge. This procedure should be performed on a cold engine.
1. Loosen the jam nut behind the oil pressure sending unit to the point where you can rotate the OPSU by hand.
2. Turn the keyswitch to ON (don't start engine)
3. Make sure there's plenty of slack in the OPSU electrical wire
4. Rotate OPSU right or left while watching oil pressure gauge
5. Find OPSU location where gauge needle points exactly to zero
6. Turn keyswitch to OFF
7. Tighten OPSU jam nut
8. Reposition OPSU electrical wire to your satisfaction

//greg//





If any of you readers out there have a Jinma tractor that has one of these adjustable oil pressure sending units ??....... and can email pictures I would love to see it if possible. I have never seen it and have never ran across it selling replacements yet ??


Thanks,
Ronald
Ranch Hand Supply
 
   / Oil Spewing out of Crankcase Breather #20  
If any of you readers out there have a Jinma tractor that has one of these adjustable oil pressure sending units ??.
Don't waste their time Ronald. You're the only one calling this an "adjustable" OPSU. The procedure I described is just what I said - a calibration; a calibration between the OPSU and the gauge. This procedure positions the OPSU diaphragm in an electrically neutral position relative to the oil in the sump.

Just so we're clear on this, the OPSU is little more than a variable resistor. With the engine running, the oil pump pushes oil against a diaphragm inside the OPSU. This "push" on the diaphragm changes the value of the resistor. It's like this: battery voltage goes through the gauge, but can only complete the circuit by seeking ground through the OPSU. The amount of electrical resistance encountered when passing through the OPSU determines the reading on the gauge. So when installing this type, the OPSU must be positioned so that no oil pressure equals zero on the gauge. If it's just screwed on haphazardly, the gauge reading is likely to be inaccurate. Screwed too far on, oil pressure reads high. Not screwed on far enough, oil pressure reads low.

So. When the engine is not running, the only oil pressure on the diaphragm is from the weight of the oil itself. Gravity. That's why the calibration is performed on a cold non-running engine. This is the one and only time that you can actually be sure of the oil pressure indicated on an electrical-type gauge. Zero. So it's the ideal time to rotate the OPSU, until the gauge actually indicates zero.

Oh, I should have mentioned oil level when I first posted the procedure. Since gravity also affects pressure, the oil level in the cold sump should be exactly at the full mark before starting the calibration process.

//greg//
 
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