Engine - Oil Pressure Too High
90porsche06 October 9, 1990Subject: Servicing Engine Oil
Pressure Relief Valve
Model Group
924S,
1
944/S/S2/T
Part Identifier Number
1726 9017
ATTENTION: Service Manager/Service Technician
Models Affected: 924S, 944/S/S2/T
Concern: The engine oil pressure relief valve should be inspected whenever oil pressure is too low or too high, and whenever the engine is overhauled. This procedure applies to original equipment valves from M.Y. 1987 and to replacement valves up to M.Y. 1986.
Figure 1:
Repair Procedure: 1. Before disassembly Using a piece of plastic, depress the sliding piston (# 4 in Figure 1) in its bore, checking for free movement. If the piston is not free and smooth the valve cannot be reused.
2. Disassembly Mount the screwcap in a vise. Using a clean shop towel, pull the housing out of the screwcap by hand. Doing so destroys the Oring (# 5 in Figure 1). Be careful of losing internal parts.
3. Inspection Clean and inspect parts. The valve cannot be reused if either damping piston or sliding piston is scored or grooved, or if there is any binding of the pistons in their bores.
Note: Due to machining/assembly tolerances, parts from different valves cannot be mixed. The valve must be replaced as a unit.
4. Assembly Lightly oil valve parts for assembly. Install O-ring (# 5 in Figure 1) on valve housing.
Caution: On some valves the damping piston may have a 45~ chamfer on one end. This end faces the screwcap.
Repair Procedure (cont.): Coat O-ring (# 5) with oil and press valve together with a
handpress or vise. Coat O-ring (# 7 in Figure 1) with oil and install on valve housing.
5. Install the valve assembly into the engine with a new seal and torque to 45 N-m. Refer to Technical Bulletin Group 1, Number 8904, page 4 for installation hints.
Figure 2:
Parts Information:
Note: For complete listing of valve applications, see Technical Bulletin Group 1, Number 8904, Book F.
Caution: Part numbers given in this bulletin are for reference only. Always check with your Parts Department for the latest parts information.