Usage:
3408 Industrial Engines
Description of Change: A larger boss is now used at a bolt hole at the rear of the cylinder block on the above model. With the larger boss the bolt hole will not be drilled into a coolant passage. This drilled passage caused coolant to leak into the engine lubricating oil. See the illustration for location of the bolt hole.
The bolt hole is used to fasten the flywheel housings that are made of aluminum. The bolt hole is not used on flywheel housings that are made of cast iron. Coolant leakage was found on some engines that have the flywheel housings that are made of cast iron.
Adaptable To: The part number of the cylinder block did not change. The larger boss was added to the cylinder block on 3408 Engines with serial numbers 67U144-up. If a coolant leak is found at the bolt hole on an earlier engine, a 4F4879 Bolt with 5P3413 Sealant on the threads can be installed to stop the leak. Do not damage the bolt hole.
Arrow shows location of bolt hole.