16704 Mercury GASKET, HEAD

1. Check each bearing cap (1) for its location on the engine. Each cap has an arrow which is toward the front of the block and a number which gives the location of that cap. Keep each bearing with the correct cap.2. Remove bearing caps No. 2 through No. 6. Remove thrust plates from No. 4 upper bearing.3. Install one of the flywheel bolts in each end of the crankshaft. Fasten a hoist to the crankshaft as shown. Remove No. 1 and No. 7 main bearing caps. Remove the crankshaft. The weight of the crankshaft is approximately 122 kg (270 lb)for the 3408 engine and approximately 180 kg (400 lb)for the 3412 engine.
Be careful not to damage the crankshaft journals when the crankshaft is removed.
4. Remove crankshaft gear (2) with Tool (A).5. Remove dowel and pin from the crankshaft with Tool (B).Install Crankshaft
1. Install pin (1) in the crankshaft end until it is extended from the surface a distance of 6.4 0.5 mm (.25 .02 in).2. Install dowel (2) until it is extended from the surface a distance of 4.1 5.0 mm (.16 .02 in). 3. Heat crankshaft gear (3) to a maximum temperature of 232°C (450°F). Install gear (3) on the crankshaft with groove (4) in alignment with dowel (2).4. Make sure the upper main bearings are clean. Put clean oil on the upper main bearings and journals of the crankshaft. 5. Install one of the flywheel bolts in each end of the crankshaft. Fasten a hoist to the crankshaft and put it in position in the block.
Use care to prevent damage to the crankshaft journals. Make sure the "V" mark on the crankshaft gear is in alignment with the "V" mark on the idler gear.
For more detail about installation of main bearings, see the topic "Remove & Install Crankshaft Main Bearings".6. Check the bearing clearances with Plastigage.7. Put 4C-5593 Anti-Seize Compoundon the bolts for caps No. 1 and No. 7. Install No. 1 and No. 7 caps with the bolts finger tight. Make sure the arrows on the caps are toward the front of the block. 8. Install thrust plates (5) for the No. 4 upper main bearing. Install the thrust plates with the side that had identification "BLOCK SIDE" toward the cylinder block.9. Put 4C-5593 Anti-Seize Compoundon the bolts for caps NO. 2 through No. 6. Install caps No. 2 through No. 6. Install cap No. 2 through No.6 with the bolts finger tight. Make sure the arrows are toward the front of the block.
Do notuse an impact wrench to tighten the bolts the additional 120 degrees(1/3 of a turn).
10. Tighten the cap bolts as follows:a. Tighten the bolts on the tab end of the caps first to a torque of 260 14 N m (190 10 lb ft).b. Tighten the bolts on the other end of the caps to a torque of 260 14 N m (190 10 lb ft).c. Put a mark across the bolt head and cap. Tighten the bolts opposite the tab end 120 degrees(1/3 of a turn). 11. Check the end play of the crankshaft with Tool (A). Make sure the dial indicator is against a machine surface. End play with new thrust plates must be 0.15 to 0.51 mm (.006 to .020 in). The maximum end play with used thrust plates is 0.89 mm (.035 in).End By:a. install pistonsb. install flywheel housingc. install front housingd. install oil pump