Section 1 - Oil Pressure Relief Valve
From start of production 1983, 944 cars came equipped with a spring and piston oil pressure relief valve (figure 1). This was used in all 944 and 944 Turbo up to the end of 1986 production. Also early 1987 924S used this system. In 1987 production of 944, 944S and 944 Turbo, a new type one-piece oil pressure relief valve PN 944 107 035 01 was installed (figure 2). Later production 1987 924S also received this valve. At around the same time a new type one-piece pressure relief valve, PN 944 107 035 11 was introduced as a retrofit to repair earlier engines from 1983 to 1986 along with the early 924S. With this, the old type spring and piston was discontinued as a spare part.
1987 engines from production date July 1986, received pressure relief valve PN 944 107 035 01. This valve was not anticorrosion treated. The engine numbers are as follows:
43 H 01920 924S/944 Manual transmission
43 H 60385 924S/944 Automatic transmission
42 H 00140 944S
45 H 00086 944 Turbo
1987 engines from production date October 1986, the oil pressure relief valve PN 944 107 035 01 received an anti-corrosion treatment. Installation in production began with the following engine numbers:
43 H 05373 924S/944 Standard transmission
43 H 61268 924S/944 Automatic transmission
42 H 02847 944S
45 H 01256 944 Turbo
When repairs are made to engines which fall between the above mentioned engine numbers, the oil pressure relief valve must be replaced with pressure relief valve PN 944 107 035 01.
Since these new type valves are similar in design, the following information will aid in determining the correct oil pressure relief valve application.
Valve Application
YEAR MODEL(S) QUALIFIER VALVE TYPE
1987 924S Up to engine # Fig. A
43 H 01919-std. trans.
43 H 60384- auto. trans.
1987 924S From engine # Fig. B
43 H 01920-std. trans.
43 H 60385-auto. trans.
1983-86 944, All Fig. A
944 Turbo
1987 944, 944S All Fig. B
944 Turbo
Part Number Information
Figure A Valve
1. Valve 944 107 035 11
2. O-Ring 944 107 935 11
3. Seal Ring N 043 815 3
Figure B Valve
1. Valve 944 107 035 01
2. O-Ring 944 107 935 01
3. Seal Ring N 043 815 3
Important Repair Hints
If the pressure relief valve is removed, always replace the aluminum sealing ring, PN N 043 815 3 and install a new O-ring.
For valve PN 944 107 035 11 use O-ring PN 944 107 935 11.
For valve PN 944 107 035 01 use O-ring PN 944 107 935 01.
Coat the relief valve O-ring and outer surface with oil to prevent binding during installation.
It is imperative that the oil cooler housing and the oil pressure relief valve bore in the engine block be perfectly aligned. If they are not, the oil pressure relief valve can be improperly loaded and may bind internally, causing excessively high or low oil pressure. Binding during removal of a misaligned one-piece pressure relief valve will cause the valve to come apart. If this occurs, the valve must not be reassembled and used. Instead, a new valve should be installed. This unit is considered a NON-serviceable part and must not be disassembled.
Alignment of the pressure relief valve bore is accomplished by using the following tools:
Where valve PN 944 107 035 01 is to be installed, use special tool 9262/1 (this tool replaces special tool 9262).
Where valve PN 944 107 035 11 is to be installed, use special tool 9215.
NOTE:
Special tool 9215 is only used in engines having a steel sleeve installed in the oil pressure relief valve passage (1983-1986). It is important that the sleeve (arrow B) be firmly installed in the crankcase. If loose, the oil cooler housing must be removed and the sleeve secured with loctite 648 or 638. Drive the sleeve to stop with special tool 9215. Consult the 944 Workshop Manual Vol. 1, page 17-22 for additional instruction.