806830T Mercruiser HEAT EXCHANGER

This engine uses high voltage to control the fuel injectors.Disconnect electronic fuel injector enable circuit connector to prevent personal injury.Do not come in contact with the fuel injector terminals while the engine is running.
Note: Valve lash is measured between the rocker arm and the valve bridge. All measurements and adjustments must be made with the engine stopped and the valves fully closed.Valve Lash Check
An adjustment is not necessary if the measurement of the valve lash is in the acceptable range. Check the valve lash while the engine is stopped. The valve lash setting is specified in Table 1.
Table 1
Quick Reference for Engine Valve Lash Setting
C-10 and C-12 Engines
Inlet Valves Exhaust Valves
Valve Lash Setting 0.38 0.08 mm (0.015 0.003 inch) 0.64 0.08 mm (0.025 0.003 inch)
TC Compression Stroke 1-2-4 1-3-5
TC Exhaust Stroke(1) 3-5-6 2-4-6
Firing Order 1-5-3-6-2-4(2)
(1) 360° from TC compression stroke
(2) The No. 1 cylinder is at the front of the engine.If the measurement is not within this range, an adjustment is necessary. Refer to "Valve Lash Adjustment" for the proper procedure.Valve Lash Adjustment
Illustration 1 g00386924
Cylinder and valve location
(A) Exhaust valves
(B) Inlet valves
Table 2
Engine Valve Lash Setting
Valves Valve Lash Setting
Inlet 0.38 0.08 mm (0.015 0.003 inch)
Exhaust 0.64 0.08 mm (0.025 0.003 inch) Adjust the valve lash while the engine is stopped. Use the following procedure to adjust the valve lash:
Put the No. 1 piston at the top center position. Refer to Testing and Adjusting, "Finding the Top Center Position For No. 1 Piston". Note: If the engine is equipped with an engine compression brake, loosen the adjusting screw for the lash on the slave piston for the compression brake prior to adjusting the engine valve lash. Refer to the Testing and Adjusting, "Slave Piston Lash - Adjust" for information that relates to the adjustment of the slave piston lash for the engine compression brake.
Before any adjustments are made, lightly tap the rocker arm at the top of the adjustment screw with a soft mallet. This will ensure that the lifter roller seats against the camshaft's base circle. Note: Refer to Table 2 for the appropriate engine valve lash setting.
Make an adjustment to the valve lash on the inlet valves for cylinders 1, 2, and 4.
Illustration 2 g00481639
Engine valve lash adjustment
Typical example
(1) Rocker arm
(2) Adjustment locknut
Loosen adjustment locknut (2).
Place the appropriate feeler gauge between rocker arm and the valve bridge. Then, turn the adjustment screw in a clockwise direction. Slide the feeler gauge between the rocker arm and the valve bridge. Continue turning the adjustment screw until a slight drag is felt on the feeler gauge. Remove the feeler gauge.
Tighten the adjustment locknut to a torque of 30 7 N m (22 5 lb ft). Do not allow the adjustment screw to turn while you are tightening the adjustment locknut. Recheck the valve lash after tightening the adjustment locknut.
Make an adjustment to the valve lash on the exhaust valves for cylinders 1, 3, and 5.
Loosen adjustment locknut (2).
Place the appropriate feeler gauge between rocker arm and the valve bridge. Then, turn the adjustment screw in a clockwise direction. Slide the feeler gauge between the rocker arm and the valve bridge. Continue turning the adjustment screw until a slight drag is felt on the feeler gauge. Remove the feeler gauge.
Tighten the adjustment locknut to a torque of 30 7 N m (22 5 lb ft). Do not allow the adjustment screw to turn while you are tightening the adjustment locknut. Recheck the valve lash after tightening the adjustment locknut.
Remove the timing bolt and turn the flywheel by 360 degrees in the direction of engine rotation. This will put the No. 6 piston at the top center position on the compression stroke. Install the timing bolt in the flywheel.
Before any adjustments are made, lightly tap the rocker arm at the top of the adjustment screw with a soft mallet. This will ensure that the lifter roller seats against the camshaft's base circle.
Make an adjustment to the valve lash on the inlet valves 3, 5, and 6.
Lightly tap the rocker arm at the top of the adjustment screw with a soft mallet. This will ensure that the lifter roller seats against the camshaft's base circle.
Loosen the adjustment locknut.
Place the appropriate feeler gauge between rocker arm and the valve bridge. Then, turn the adjustment screw in a clockwise direction. Slide the feeler gauge between the rocker arm and the valve bridge. Continue turning the adjustment screw until a slight drag is felt on the feeler gauge. Remove the feeler gauge.
Tighten the adjustment locknut to a torque of 30 7 N m (22 5 lb ft). Do not allow the adjustment screw to turn while you are tightening the adjustment locknut. Recheck the valve lash after tightening the adjustment locknut.
Make an adjustment to the valve lash on the exhaust valves for cylinders 2, 4, and 6.
Loosen adjustment locknut (2).
Place the appropriate feeler gauge between rocker arm and the valve bridge. Then, turn the adjustment screw in a clockwise direction. Slide the feeler gauge between the rocker arm and the valve bridge. Continue turning the adjustment screw until a slight drag is felt on the feeler gauge. Remove th