View Full Version : HC8075 - oil pressure

30-11-2013, 09:50 AM
I have problem with Gram reciprocating compressor.

When oil is cold and the compressor starts, the oil pressure is 2,9 bar.
After operating for 20 minutes on 100% capacity, oil pressure gradually dropping to 1 bar, and the compressor stops.
After standing ca 30min, and starting compressor, the pressure was 1,5 bar, and again slowly falling.

Oil filter and oil have been changed recently.

Any help will be appreciated!

30-11-2013, 10:11 AM
Most probably mechanical wear, as the viscosity of the oil thins.
Which will happen as it warms up there is less resistance to the oil flowing around the lubricated parts.
End result the oil pressure drops until the oil diff actuates!
Alternatively during say a recent rebuild? (You mention an oil change) Something has not been reassembled correctly?
My first thought would be excessive wear, but without more details I cannot be precise.

30-11-2013, 09:33 PM
Maybe try to adjust oil pressure regulator if filters clean etc.

Because its easy adjust it and /or check it.

Also is sump oil clear of foam & what is oil temperature?

What is model of compressor as oil differential trip on some models is 2.5 bar.

01-12-2013, 09:33 PM
The compressor was rebuilt a year ago, and worked fine since.
The customer changed oil and filter, and after restarting, oil problem occured.
Trip is to be at 2 bars, so there is something wrong with control system, allowing compressor to run..
I'll go on site Tuesday, will know more than.

07-12-2013, 02:40 AM
I have worked on only one Gram recip and it was possible to install the oil filter incorrectly from memory. Also check the right oil has gone in. Or maybe the operators adjusted the oil regulating valve to over come partly blocked oil filter?