To install the thermostat you must first drain
your coolant down to a level just below the cylinder head in an upright
engine installation. In an inverted installation the system must be
drained until their is no fluid in the engine.
Next use a Philips screw driver and loosen the two
clamps which are used to hold the rubber intake sockets onto to the intake
manifold, you only need to loosen one clamp on each carb.
Once this has been accomplished you need to remove
the two nuts, lock washers and flat washers holding the top of the rotary
valve tank bracket.
You must also remove the two TOP 13 mm head bolts,
lockwashers and flat washers from the top of the intake manifold
Now gently pull out on the coil mounting plate
until it is clear of the two top two studs. You may have to slacken off
the spark plug wires to do this. Remove the water outlet socket. Behind it
you will find a rubber O ring remove it.
Now to install the thermostat first install the
NEW rubber O ring that comes with the thermostat, ONTO the thermostat. The
thermostat fits into the MIDDLE of the O ring. That is there is a slit in
the middle of the NEW "O" ring place
the thermostat into it. Once the O ring has been installed onto the
thermostat, place the thermostat with the "POINT" of the
thermostat facing out, the "FLAT" side facing in and the two
holes in the outside ring of the thermostat facing UP toward the sky!
Reinstall the water outlet socket. Reinstall the
coil mounting plate. Reinstall the two nuts, lockwashers, and flat
washers. Reinstall the two 13 mm nuts with their flat washers and
Torque the 10 mm bolts/nuts to 98 inch lbs. Torque the
13 mm head bolts to 155 inch lbs. This torque IS NOT what is
recommended in your manual! BUT if you torque to 195 inch lbs. you will
likely strip the threads in the casing! The casing has only a few
threads in it, if you strip them it is a very expensive job to have them
Fill your system up with fluid, with the
thermostat installed fluid has to come in from the lower water outlet, it
may take a couple of minutes depending on the installation to get up into
the engine. Remember use distilled water or corrosion will start inside