803560T04 Mercury ECU, Engine Control Unit

1. Install two 3/4"-10NC guide pins (1) in the end of the crankshaft as shown.2. Use a bar and a wood block to hold the crankshaft in position when the timing gears are removed. 3. Remove the lock and nut (2) that hold the camshaft drive gear in position.4. Install nut (2) back on the camshaft until it is even with the end of the camshaft. 5. Remove camshaft drive gear (3) with tooling (A). Remove the nut and the camshaft drive gear. 6. Remove two bolts (5) and the locks.7. Remove washer (6).8. Remove idler gear (4). 9. Remove two bushings (7) and spacer (8) from the idler gear with tooling (B). 10. Remove two bolts (10) and lock that hold idler gear (9) in position. 11. Remove retainer (12) and wahser (11). Remove idler gear (9) from the shaft. 12. Remove washer (13) from the shaft. 13. Remove two bearings (14) from the idler gear with tooling (C).Install Timing Gears
1. Turn the crankshaft until No. 1 piston is at top center compression stroke. Hold a string from the center of the accessory drive shaft to the center of the crankshaft as shown. Make sure the mark on the accessory drive gear is in alignment with the mark on the crankshaft gear. The marks must be in a straight line with the center of the accessory drive shaft and the center of the crankshaft. 2. Heat the camshaft drive gear (1) in oil to a maximum temperature of 400°F (204°C). Install the drive gear on the end of the camshaft. 3. Install the lock and nut (2) on the end of the camshaft. Tighten the nut to a torque of 300 lb.ft. (406.7 N m).4. Turn the camshaft until the mark on the camshaft drive gear is in alignment with the bolt hole in the timing gear housing assembly. Install a 3/8"-16NC bolt (3) 3 in. (76.2 mm) long in the timing gear housing assembly to hold the camshaft in position. 5. Remove water line (4) from the aftercooler and the cylinder block.6. Remove cover (5) from the fuel pump and governor drive housing. 7. Turn the fuel pump drive gear until timing pin (6) can be installed in the camshaft for the fuel injection pump housing as shown. 8. Install the two bearings in the idler gear with tooling (A). Install the bearings until they are .150 in. (3.81 mm) below the outside surfaces of the idler gear. 9. Install washer (7) on the shaft. The flat side of the washer must be against the idler gear when it is installed. 10. Install idler gear (8) on the shaft. 11. Install washer (9) on the shaft. Install retainer (10) the lock and the two bolts that hold the retainer in position. 12. Remove cover (11) from the fuel pump and governor drive housing. 13. Remove four bolts (12) and locks from the shaft. This will allow the fuel pump drive gear to turn, but the camshaft in the fuel injection pump housing will not turn. The fuel pump drive gear must turn freely in order to install the last idler gear.14. Install one of the bushings in the idler gear with tooling (B). Install the bushing even with the outside surface of the idler gear.15. Turn the idler gear over. Install the spacer. 16. Install the other bushing in the idler gear with tooling (B). Install the bushing even with the outside surface of the idler gear. 17. Install idler gear (13) on the shaft. If necessary turn the fuel pump drive gear to get the gears to engage correctly.18. Install the washer, lock and the two bolts that hold the idler gear in position. 19. Install four bolts (14) and two locks in the shaft. 20. Remove timing pin (15) from the camshaft and install it in its original position in the fuel pump and governor drive housing. 21. Install two covers (16) on the fuel pump and governor drive housing.22. Install the water line from the aftercooler to the cylinder block.end by: a) install crankshaft rear seal ring and throwerb) install flywheel housingc) install rocker shaft assemblies