Installation manual
ENGINE 
COOLANT 
CHANGING 
THE 
COOLANT 
The engine's coolant must be changed every eight to 
twelve months depending on the engine's use. 
If 
the 
coolant is allowed to become contaminated, it can lead 
to overheating problems. 
A coolant recovery tank allows for engine coolant expan-
sion 
and 
contraction during engine operation, without 
any 
sig-
nificant loss 
of 
coolant and without introducing air into the 
cooling system. This tank should be located at or 
above 
the 
engine manifold level, and be easily accessible. 
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COOLANT 
RECOVERY 
TANK 
CAP 
~---
COOLANT 
RECOVERY 
TANK 
COOLANT 
EXPANSION 
Drain the engine coolant by loosening the drain plug on 
the engine block and opening the manifold pressure cap. 
Flush the system with fresh water, then start the refill 
process. 
See the Parts Identification photos in this man-
ual for locations. 
NOTE: 
The petcock on the heat exchanger can also be 
used to drain engine coolant. 
A 
WARNING: 
Beware 
of 
the 
hot 
engine 
coolant. 
Wear 
protective 
gloves. 
TO 
REFILL 
WITH 
COOLANT 
With the enginge running in idle, slowly pour clean 
premixed coolant into the manifold. 
NOTE: 
Open the air bleed petcock on the heat exchanger 
to help remove air from the system. When a steady flow 
of 
coolant appears 
at 
the drain plug opening, close the 
water drain plug and continue to fill the system until the 
manifold remains full.  Close the petcock on the heat 
exchanger when antifreeze flows from 
it. 
Start the engine and bring it to operating temperature. 
Monitor the coolant in the manifold and add as needed. 
Fill the manifold to the filler neck and install the pressure 
cap. 
Remove the cap on the coolant recovery tank, fill with 
coolant to halfway between 
LOW 
and MAX, and replace 
the cap. 
Run the engine and observe the coolant expansion flow 
into the recovery tank. 
After checking for leaks, stop the engine and allow 
it to cool. Coolant should draw back into the cooling 
system as the engine cools down. Add coolant to the 
recovery tank 
if 
needed. Clean up any spilled coolant. 
NOTE: 
Periodically check the condition 
of 
the pressure cap. 
Ensure that the upper and lower rubber seals are in good 
condition and check that the vacuum valve opens and 
closes tightly.  Carry a spare cap. 
THERMOSTAT 
A thermostat, located near the manifold at the front 
of 
the 
engine, controls the coolant temperature as it contin-
uously flows through the closed cooling circuit. When 
the engine is first started the closed thermostat prevents 
coolant from flowing (some coolant is by-passed through 
a hole in the thermostat to prevent the exhaust manifold 
from overheating). As the engine warms up the thermo-
stat gradually opens. The thermostat is accessible and can 
be checked, cleaned, or replaced easily. Carry a spare 
thermostat and gasket. 
THERMOSTAT 
WATER 
TEMPERATURE 
ALARM 
WATER 
TEMPERATURE 
SENDER 
I~l 
WSJ&lBEKE 
I Engines & GeneratDrs 
13 










