ORCA
MARINE COOLING SYSTEMS
BELLINGHAM, WA 98226
Mercruiser 233 Installation instructions 300081
1974 - 1986 Full system
1. Disconnect battery. Drain system according to manufacturer’s instructions. Remove all hoses at the thermostat housing. Remove the
1-3/4” hose at the circulating pump. Remove the thermostat housing, clean the gasket surface and install the new KA-111 water outlet with the #7 gasket and the 3/8 x 1 HCS and lock washers. DO NOT REPLACE THE THERMOSTAT HERE.
2. Remove the spark plug wire looms from the front of each head. Install the KA-131 bracket in the same hole on the starboard head. Use the original bolt and the 7/16” lock washer provided. Attach the spark plug loom to the bracket with the 3/8 x 1 HCS and lock washer. Attach the KA-132 bracket to the port head.
3. Connect the original 1” hoses on the inside, lower fitting on the exhaust manifolds to the KA-111 water outlet on the front of the engine. These are the antifreeze in to the heat exchanger. Temporarily remove the hoses from the front of the exhaust manifolds.
4. Remove the 3/8 plugs from the intake manifold ( port side, rear of distributor ) and the circulating pump. Thread the 5/8H x 3/8M brass hose elbow into the intake manifold and the 5/8H x 3/8M brass hose barb into the circulating pump. Connect the two fittings with the 5/8 x 26 wire hose unless you are installing a heater.
HEATER INSTALLATION: The pressure ( inlet ) to the heater will come from the brass elbow on the intake manifold. The suction ( outlet ) from the heater will connect to the hose barb on the circulating pump.
5. Remove the exhaust elbows, carefully clean the gasket surfaces and install the new #1 block-off gaskets under the elbows.
6. Set the cushion tape on the brackets and loosely clamp the heat exchanger in place with the #88 ss clamps. Use the hoses removed in step 3 to connect the in-line thermostat housings between the front of the exhaust manifoldsand the heat exchanger. Make sure the flow direction is going from the exhaust manifold to the heat exchanger.
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7. Measure, cut and install the 1-3/4” wire hose connecting the circulating pump to the heat exchanger. This is the antifreeze out to the engine. Do the same with the 1-1/4” hose connecting the outdrive to the heat exchanger. This is the raw water in.
8. Use the 1 x 3 hose and the 1 x 15 hose to connect the exhaust manifolds to the 1 x 1 x 1-1/4 copper tee. Use the 1-1/4 x 28 hose to connect the copper tee to the heat exchanger. This is the raw water out from the heat exchanger.
9. Adjust the heat exchanger and all new parts and tighten clamps. Use cable ties to secure any hose away from a moving belt or engine part. Fill the system with a maximum 50/50 mix of antifreeze and distilled water. Reconnect battery, idle engine to temperature and check for leaks.
CAUTION:
INSTALLATION OF THE COOLANT RECOVERY BOTTLE IS CRITICAL TO THE OPERATION OF THIS SYSTEM.
IT MAY BE INSTALLED ANYWHERE BUT MUST MAINTAIN THE LIQUID LEVEL IN THE BOTTLE BETWEEN THE WARM AND COLD LINES AT ALL TIMES.
THE RECOVERY BOTTLE ALLOWS FOR EXPANSION AND CONTRACTION OF THE ANTI-FREEZE SOLUTION IN NORMAL OPERATION AND HELPS KEEP THE SYSTEM FULL.
6 October 2006