Cummins B Series Engine Rebuilds - Engine Builder Magazine

Cummins B Series Engine Rebuilds

The Cummins B Series engine was developed by Cummins for use in a variety of industrial applications such as aircraft tugs, wood chippers, drill rigs, material handling equipment, etc. The B Series engine was developed as an American alternative to Perkins, Deutz and other industrial engines in the 70-150 HP range. Unlike those industrial engines however, the Cummins B Series does not have replaceable sleeves or liners. As a result, when it is time for an overhaul the cylinder block bores must be machined to a larger oversize and new pistons fitted. Unfortunately, because of this, the B Series engine can’t be rebuilt in the field and it is unfairly labelled a "throw-away engine."

As an industrial engine, the Cummins 4B engines are often run to within an inch of their life. Sometimes the operators forget to do their "dailys" and don’t check the oil level and the engine is run while low on lube oil. Consequently, the B Series lube oil can get hot and the main and rod bearings suffer and have a short service life. If run too hard, too long the crankshaft can be damaged. To prolong the life of your remanufactured engines it is recommended that you install a remote oil filter. This is good insurance against a damaged crankshaft.

For those who want to rebuild Cummins B Series engines, Foley stocks complete engine overhaul parts kits and brand new crankshafts.

– Tech Tip courtesy of Foley Engines (

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