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KMP Main Bearing Set U5MB0026A (0.010" undersize)
The KMP Main Bearing Set U5MB0026A (0.010" undersize) supplies every main journal shell for a crankshaft rebuild under one part number, U5MB0026A. This set is 0.010" undersize.
About this part
The crankshaft rides on these shells for every hour the engine runs. They depend on clean oil at pressure, so contaminated oil or a failed pump shows up here first.
When to replace it
- A dull rumble from the bottom of the block at start-up
- Oil pressure that drops away as the engine warms
- Excessive crankshaft end float or movement
- Metal particles in the oil filter
Before you order
Order standard shells for a crank in original size, or the undersize that matches a reground crank. Check thrust washers at the same time; they are often replaced with the mains.
If the old part has no readable number, send us a clear photo with the engine or alternator nameplate and we will identify it before you buy.
Questions
What does the size on the set mean?
STD is a standard-size shell for an unground crankshaft. Sizes such as 0.010" or 0.25 mm are undersize shells for a crankshaft ground down by that amount.
Do main bearings come with thrust washers?
Not always. Thrust washers are often a separate part number; ask us and we will check what your set includes.
Specifications
| Part number | U5MB0026A |
|---|---|
| Brand | KMP Brand |
| Range | Main Bearing Sets |
| Size | 0.010" undersize |
Not sure it fits?
Send us the number on your old part, or a photo with the engine or alternator nameplate, and we'll confirm the match.
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