9/1/2004
When can I reuse connecting rods for Mercedes-Benz M111 engines?
When can I reuse connecting rods for Mercedes-Benz M111 engines?
If you're rebuilding Merecedes connecting rods for resale or reuse, pay attention to the following information from the AERA Technical Committee The 1994-'98 2.2L Mercedes Benz M111 engines. This information should be considered anytime machine work is being done for component reuse.
Examine all connecting rods for blue discoloration and if found replace the connecting rod! CAUTION: When replacing connecting rod(s), rod set must be balanced within 4 grams. Adjust if necessary by removing weight from the balancing pad.
Checking:
Torque mounting bolts to 33 ft/lbs + (45 Nm) 90°.
Measure rod basic bore (D1 & d1), refer to the specifications below. NOTE: If basic bore is conical or if the diameter (D1 & d1) is greater than the maximum value, resize bores.
Machining:
If big end requires resizing, machine off of the rod bearing cap at contact surface by not more than .008? (.02 mm). Then, machine big end to 2.0315-2.0323? (51.60 - 51.62 mm).
If pin bushing end requires resizing, install new bushing making sure to align oiling holes and machine inside diameter to .8664-.8666? (22.007-22.013 mm).
Any thoughts on the cause of an oil leak on an '89 Honda CRX?
The AERA Technical Committee offers the following information regarding an engine oil leak on 1989-'91 Honda 1.5 & 1.6L engines. Some vehicles that were produced during the mentioned years may have an oil leak around the spark plug well. The spark plug area of the camshaft holder casting could be porous and may leak.
If normal diagnosis and repairs do not fix the above-mentioned concern, installation of a new cam holder kit, p/n 041 01-PM3-308, c/n 3046497, will be required. To properly install the new kit, it is necessary to removal the spark plugs and valve cover. Upon removal of the valve cover, inspect valve cover rubber seals. If any signs of damage have occurred, replace rubber seals as needed.
Turn the engine to TDC and remove the timing belt adjuster and remove the timing belt and the rocker arm assembly. Check clearance between the new camshaft holders and the camshaft by coating the new cam holder with oil and install them without the rocker arms and shafts. Install the required bolts and torque them to 16 ft/lbs. While using an INCH lb torque wrench, turn the camshaft and check the amount of force. If the turning torque is greater than 112 in/lbs, the camshaft holder may need to be polished.
If the holders need to be polished, rotate the camshaft several times to establish contact marks inside the holders. Remove the holders and inspect for contact marks on the surface. Polish the marks with a #500 grit emery paper and then finish with a #800 grit emery paper. Wash the camshaft holder and install so that turning torque can be checked. If turning torque is still not acceptable, continue with the polishing process.
NOTE: Incorrect turning torque can result in camshaft seizure due to insufficient clearance.
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