Engine - Low, Pulsating, or Slow Ascent of Oil Pressure
83porsche03Subject
Engine Oil Pressure
Part Identifier N/A
Applies To 944
1983
Group
17
Key Points
Repair instructions for low, pulsating, or slow build-up of oil pressure.
C
Number
83-03
Sept. 15, 1983
Isolated cases have been reported on vehicles with low, pulsating, or slow build-up of oil pressure. Following, are some procedures for troubleshooting vehicles displaying these symptoms:
External Engine
Only oil filters with integral check valve, Part Number 944 107 201 03, are to be used (928 oil filter has same dimensions, but is not equipped with integral check valve.)
At oil filter changes, squirt some oil into the threaded bore of the oil filter flange before installing filter.
Check function of instrumentation and wiring as follows:
- remove blue/black wire from terminal WK of the oil pressure switch. With ignition ON, the oil pressure indicator light should not be on. If it is, check wiring.
- remove blue/white wire from terminal G of oil pressure switch. With ignition ON, oil pressure gauge should move to maximum reading. If not, first inspect wiring. If wiring OK, replace gauge.
- if wiring, gauge and indicator light operate as indicated above and gauge still indicates incorrect oil pressure, replace oil sending unit;
Part Number: 928 606 203 01.
Internal Engine
Remove piston from oil pressure relief valve and clean thoroughly. Piston must be clean and without damage; if necessary, replace piston, Part No. 944 107 171 08.
Check oil pressure relief valve spring for following:
Free length: 78.4 mm
O.D. : 11.8 mm
Wire diameter: 1.8 mm
Replace spring if necessary; Part No. 944 107 172 02.
Before installing piston, crank engine to pump out any foreign particles.
CAUTION
Piston can bind due to improperly installed oil cooler housing. When installing housing, use piston to properly align housing with engine block. ( A special tool is forthcoming).
Check for cracked or broken oil suction pipe Part Number 944 107 032 06. Flange has been reinforced in production as of:
Engine No. 43D3225/43D5887
Production Date: September 3, 1982
Check sealing of the oil suction pipe:
* Minimum height: 7.1 mm
Either of these situations can be diagnosed by adding 3 additional quarts of oil to engine and running at a fast idle only. If oil pressure normal, a problem with the oil pickup pipe or seal is present. Be sure to drain additional oil when test is completed.
Oil pump can function correctly only if front pulley bolts maintain their specified torque of 250 N-m.
During repair of crankshaft or oil pump, assure that correct washers are installed:
Washer Part Number: 944 102 210 00; fits short nosed crankshaft, Part No. 944 102 015 07.
Washer Part Number: 944 102 210 01: fits long nosed crankshaft, Part No. 944 102 015 08.
CAUTION
Part numbers are for reference only. Always check with your Parts Department for latest parts information.