HOOD & GUARD GP 2926010 - Caterpillar

And Install Connecting Rod Bearings
START BY:a. remove oil pumpb. remove oil pan plate
3306 Engine Shown1. Turn the crankshaft until two pistons are at the bottom center. Remove connecting rod caps (1) from the two connecting rods. Remove the lower half of the rod bearing from the rod bearing cap.
The connecting rod bolts are loose on the connecting rods and can fall out when the nuts are removed.
2. Push connecting rods (2) away from the crankshaft. Remove the upper half of the rod bearing from the connecting rod. Install the connecting rod bearings dry when the clearance checks are made. Put clean engine oil on the connecting rod bearings for final assembly.
Be sure the tabs in the back of the connecting rod bearings are in the tab grooves of the connecting rod and cap.
3. Install the upper half of the rod bearing in the connecting rod, and put the connecting rod in position on the crankshaft.4. Install the lower half of the rod bearing in the connecting rod cap. The serviceman must be very careful to use Plastigage correctly. The following points must be remembered:a. Make sure that the backs of the bearings and the bores are clean and dry.b. Make sure that the bearing locking tabs are properly seated in their slots.c. The crankshaft must be free of oil where the Plastigage touches it.d. 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.e. Put a piece of Plastigage on the crown of the bearing half that is in the cap. Do nol allow the Plastigage to extend over the edge of the bearing.f. 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.g. Do not turn the crankshaft with the Plastigage installed.h. Carefully remove the cap but do not remove the Plastigage. Measure the width of the Plastigage while it is in the bearing cap or on the crankshaft journal. Do this by using the correct scale on the package. Record the measurements.j. 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 specification 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. SEBD0531.5. Use Plastigage (A) to check the connecting rod bearing clearance.6.