834985 1 Mercury GROMMET

START BY:a. remove oil pump 1. Check each connecting rod cap for its location on the crankshaft. Each cap must have a number (1) which is the same as the number on the connecting rod. Do not mix bearings.2. Turn the crankshaft until two of the pistons are at the bottom center.3. Remove connecting rod caps (2). Remove the lower bearing from the connecting rod caps.4. Push the connecting rods away from the camshaft, and remove the upper bearings.
Be careful not to damage the crankshaft journals. Do not turn the crankshaft while any of the connecting rod caps are removed.
Install the bearings dry when the clearance checks are made. Put clean engine oil on the bearings for final assembly.5. Clean the surfaces where the bearings fit. Install the upper half of the bearing in the connecting rod. Pull the connecting rod slowly onto the crankshaft.6. Install lower half of the bearing in the cap.
When the connecting rod caps are installed, make sure that the numbers on the side of the caps are next to and in alignment with the number on the side of the connecting rods.
The serviceman must be very careful to use Plastigage correctly. The following points must be remembered.... Make sure that the backs of the bearings and the bores are clean and dry.... Make sure that the bearing locking tabs are properly seated in their slots.... The crankshaft must be free of oil where the Plastigage touches it.... If the main bearing clearances are checked with the engine upright or on its side, the crankshaft must be supported. Use a jack under an adjacent crankshaft counterweight, and hold the crankshaft against the crown of the bearing. If the crankshaft is not supported, the weight of the crankshaft will cause incorrect readings.... Put a piece of Plastigage on the crown of the bearing half that is in the cap. Do not allow the Plastigage to extend over the edge of the bearing.... Install the bearing cap using the correct torque-turn specifications. Do not use an impact wrench. Be careful not to dislodge the bearing when the cap is installed.... Do not turn the crankshaft with the Plastigage installed.... Carefully remove the cap, but do not remove the Plastigage. Measure the width of the Plastigage when it is in the bearing cap or on the crankshaft journal. Do this by using the correct scale on the package. Record the measurements.... Remove the Plastigage before reinstalling the cap.When using Plastigage, the readings can sometimes be unclear. For example, all parts of the Plastigage are not the same width. Measure the major widths to make sure that they are within the specifications range. Also, experience has shown that when checking clearances tighter than 0.10 mm (.004"), the readings may be low by 0.013 to 0.025 mm (.0005 to .0010"). Out-of-round journals can give faulty readings. Also, journal taper may be indicated when one end of the Plastigage is wider than the other.For complete details concerning measuring bearing clearances, see Engine Bearings And Crankshafts, Form No. SEBD0531.7. Check the bearing clearance with tool (A) as follows:a. Put 2P2506 Thread Lubricant on the threads of the rod bolts and seat surfaces of the nuts.b. Install the caps, tool (A) and the nuts finger tight.
Do not use an impact wrench to tighten the nuts the additional 120°.
c. Tighten each nut to a torque of 80 8 N m (60 6 lb.ft.).d. Put a mark across the nuts and bolts. Tighten the nuts 120° more.8. Remove the caps and tool (A). Make sure the connecting rod bearing caps are installed with their identification number in alignment with the connecting rod number.9. Measure the width of the Plastigage to find the bearing clearance. The clearance for new bearings must be 0.071 to 0.168 mm (.0028 to .0066"). The maximum clearance for used bearings is 0.25 mm (.0.010").10. Install the caps. Tighten the nuts to a torque of 80 8 N m (60 6 lb.ft.). Tighten the nuts 120° more.11. Do Steps 1 through 10 for the other connecting rod bearings.END BY:a. install oil pump