Reassembly; Testing The Oil Pressure; Oil Pressure Switch - Westerbeke 38B FOUR Service Manual

LUBRICATION SYSTEM SERVICE
3. Rotor to cover clearance. With the outer rotor inserted in
the pump body, insert a straightedge and check the clear-
ance between the rotor and the straightedge with a feeler
gauge. If excessive, replace either the rotor or the body.
ROTOR TO COVER CLEARANCE
4.
Pump body O-ring. Check the pump body O-ring for
cracks and damage.
S. Oil pressure switch/sender: Replace the oil pressure
switch and the oil pressure sender. On propulsion
engines, the oil pressure switch is norma]]y open. On
generators, this switch is normally open;
it
closes when
the oil pressure gets to
5-10
psi.
A
CAUTION:
Oil Pressure Switch - Do not use
lock pliers, vise grips or pipe wrenches on the oil
pressure switch. Use the correct socket which is
available from Snap-On, Proto, New Britain and oth-
ers. Damage to the switch will cause oil leaks
and/or switch failure.
REASSEMBLY
1. Install the oil filter and tighten fully by hand. (Tightening
torque: 1.1 to 1.3 kg-m.) Before installation, check for
proper fitting of the O-ring in the groove and coat the 0-
ring with a small quantity of oil.
2. Install the gasket. Then install the oil pump housing, 0-
ring, rotor assembly and cover assembly in that order.
Apply oil to the rotating parts.
3. With sealant applied to the threaded portion, screw in the
oil pressure switch taking care not to close the oil hole
with sealant.
4. Apply liquid teflon sealant to the threaded portion of the
oil pressure sender. Take care not to close off the oil hole
into the sender. Thread the sender into its fitting on the
oil pump's housing.
TESTING THE OIL PRESSURE
1. Start and warm up the engine.
2. Check for oilleaks at the filter and pump assembly.
3. Remove the oil pressure sender and connect a mechanical
oil pressure gauge to the hole.
4.
Set the engine speed at
3000
rpm and measure the oil
pressure.
It should be fairly constant at 3.5 kg/cm2
(50
Ib/in2).
NOTE:
Insure that oil meets specification standards: Class
CF or CG-4 or better/SAE 30 wt.
OIL PRESSURE SWITCH
1.
Later propulsion engines and all generators have a two-
prong oil pressure/water temperature switch. When the
oil pressure drops to
5-10
psi, this switch interrupts the
circuit for the fuel run solenoid by opening, shutting
down the engine/generator.
On early propulsion engines, this switch activates an
alarm that emits a pulsating signal when the oil pressure
drops too low (5-10 psi).
NOTE:
This alarm will also emit a pulsating signal when
the engine starts up, as the oil has not yet reached its
normal pressure (a good check o/the alarm).
NOTE:
If this alarm emits a continuous signal (propulsion
engines only), it indicates an engine overheat, with the
operating temperature reaching
210~
OIL PRESSURE ....
+
+
t-
OIL
PRESSURE
t-
OIL
PRESSURE
'ARLY PROPULSION
"1
ENGINE MODELS
%
P
LATER PROPULSION
~
ENGINE MODELS
,ALL GENERATOR
J
MODElS
. OIL PRESSURE SWITCHES
Engines & Generators
36