20. Engine Block Cleaning and Inspection

Engine Block Cleaning and Inspection

Special Tools
* J 7872 - Magnetic Base Dial Indicator
* J 8087 - Cylinder Bore Gage

For equivalent regional tools, refer to Special Tools (Special Tools).




1. Clean the sealing material from the gasket mating surfaces.
2. Clean the engine block and lower crankcase in a cleaning tank with solvent appropriate for aluminum.
3. Flush the engine block with clean water or steam.
4. Clean the oil passages.
5. Clean the blind holes.
6. Spray the cylinder bores and the machined surfaces with engine oil.
7. Inspect the threaded holes. Clean the threaded holes with a rifle brush. If necessary, drill out the holes and install thread inserts. Refer to Thread Repair (Overhaul).




8. Refer to Engine Mechanical Specifications (Specifications). If the deck surface is out of specification, replace the block. Do not machine the block.
9. Inspect the oil pan rail for nicks. Inspect the front cover attaching area for nicks. Use a flat mill file to remove any nicks.




10. Clean the sealing material from the gasket mating surfaces on the lower crankcase engine block side.




11. Clean the sealing material from the gasket mating surfaces on the lower crankcase oil pan side.




12. Inspect the mating surfaces of the transmission face.

Caution: A broken flywheel may result if the transmission case mating surface is not flat.

13. Use the following procedure in order to measure the engine block flange runout at the mounting bolt hole bosses:

1. Temporarily install the crankshaft. Measure the crankshaft flange runout using the J 7872 - dial indicator
2. Hold the gage plate flat against the crankshaft flange.
3. Place the dial indicator stem on the transmission mounting bolt hole boss. Set the indicator to 0.
4. Record the readings obtained from all of the bolt hole bosses. The measurements should not vary more than 0.203 mm (0.008 in).
5. Recheck the crankshaft flange runout if the readings vary more than 0.203 mm (0.008 in).




14. Inspect the crankshaft main bearing bores. Use the J 8087 - gage to measure the bearing bore concentricity and alignment. Refer to Engine Mechanical Specifications (Specifications).
15. Replace the engine block and bed plate if the crankshaft bearing bores are out of specification.




16. Inspect the cylinder bores using the J 8087 - gage. Inspect for the following items:

* Wear
* Taper
* Runout
* Ridging

17. If the cylinder bores are out of specification, replace the block. Refer to Engine Mechanical Specifications (Specifications).