Rotary Car Club - View Single Post

cewrx7r1 · 05-31-2008, 10:34 PM

It is hard for an oil pressure regulator to fail because it is a very simple device.
A spring and a plunger.

The rear OPR is what mainly regulates the max pressure to the engine after the filter.
The front regulator is more for safety. It prevents over pressurizing the oil sytem from the front cover to the filter. What if the filter clogged up. The OP gauge would show low pressure and the front OPR would dump the excess pressure saving the filter and oil cooler and lines. Same if one of the oil lines clogged or was bent.

With all the OP sending units that I have replaced since 1992, they have always shown high pressure, only the low end was off or jerky.

05-31-2008, 10:34 PM	#9
cewrx7r1 The Judge Join Date: Feb 2008 Posts: 196 Rep Power: 18	It is hard for an oil pressure regulator to fail because it is a very simple device. A spring and a plunger. The rear OPR is what mainly regulates the max pressure to the engine after the filter. The front regulator is more for safety. It prevents over pressurizing the oil sytem from the front cover to the filter. What if the filter clogged up. The OP gauge would show low pressure and the front OPR would dump the excess pressure saving the filter and oil cooler and lines. Same if one of the oil lines clogged or was bent. With all the OP sending units that I have replaced since 1992, they have always shown high pressure, only the low end was off or jerky.