An oil pressure regulator valve maintains stable lubricating oil pressure within the engine, regardless of the oil temperature. Oil leaving the pump under pressure passes into the pressure relief valve. The valve is installed into a vertically drilled passage in the balance assembly. See Figure 24357 .
Oil Pressure Regulator and Relief Valve Mounting
The oil pressure regulator consists of a valve body, a hollow, piston-type valve, a spring, a spring seat and a pin to retain the valve assembly within the valve body. See Figure 24380 .
2. Pressure Regulator Pin Location
3. Pressure Relief Valve Pin Location
7. Spring Seat
4. Valve Body
Oil Pressure Regulator and Relief Valve Details
The valve is held on its seat by the spring, which is compressed by the pin in back of the spring seat. The entire assembly is bolted to the balance support and sealed against leaks by a gasket between the block and valve body. When conditions are such that the oil pressure at the regulator valve exceeds 427 kPa (62 lb/in.2 ), the valve begins to be forced from its seat and oil from the engine gallery is bypassed to the engine oil pan. Thus, stable lubricating oil pressure is maintained at all times.
Note: Whenever the lubricating oil pump is removed for inspection, remove the regulator valve and spring and thoroughly clean and inspect them.
To determine if repair is possible or replacement is necessary, perform the following procedure. See Figure 21750 .
Flowchart for Repair or Replacement of Oil Pressure Regulator Valve
Precleaning is not necessary.
Remove the oil pressure regulator valve as follows:
Disassemble the oil pressure regulator valve as follows:
To avoid injury from flying parts when working with components under spring tension, wear adequate eye protection (face shield or safety goggles).
Inspect the oil pressure regulator valve as follows:
To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.
Assemble the regulator valve as follows:
Note: The valve body has two retaining pin holes. Install the pin in the outermost hole for the regulator valve. The retaining pin must be positioned correctly so the proper valve opening pressure will be obtained. Although the same casting is used for both the pressure regulator and relief valves, the regulator valve has a slightly larger opening machined into the side. See Figure 20438 .
Comparison of Pressure Regulator and Relief Valve Assemblies
Install the oil pressure regulator valve as follows:
Note: Detroit Diesel has determined that, when the oil pressure regulator is properly fastened to the cylinder block, a gasket between the block oil gallery and the valve body is not required. Due to the flatness tolerances of the valve face and the block mounting surfaces, the seepage of lubricating oil around the valve body at this joint is minimal and has no significant effect on oil system pressure requirements. For this reason, the regulator valve-to-block gasket has been eliminated from all Series 50 engines.