Crankshaft Grinding

Friction is the Enemy of All Engines

What is Crankshaft Grinding, and Why is it Needed?

Over time, an engine's crankshaft rod and journals (where the pistons connect to the crankshaft) will become more abrasive due to normal wear, or even subtle damage caused by bearing decay and/or destruction. Smoother journals equal better efficiency and longer engine life. 

The crankshaft grinding process consists of removing a tiny amount of material from the rod and main journals to rebuild the overall part back to OEM specifications. Having a perfectly smooth journal is essential to the efficiency of movement in the piston firing action of the engine. Therefore, the full multi-step crankshaft remanufacturing process is very intensive, but is critical to a complete engine rebuild.

Once the grind is completed, there is going to be quite a bit of excess clearance. This new clearance must be brought back to factory tolerances, because grinding makes the new journal size smaller. This is accomplished by installing new bearings which are sized to compensate for the clearance difference, providing proper OEM clearances for oil flow at the diameter of the journal.

Why UCF? Our capabilities extend from small automotive and industrial cranks up through larger agricultural diesels. We have multiple machinists trained in grinding to minimize turn around time. Proper lubrication is the life blood of an engine. This includes proper oil pressure, not just flow. Don’t risk a future engine failure due to excessive bearing clearances bleeding off oil pressure. Have your crankshaft precision ground to set the proper oil clearances in your engine to maximize oil pressure and longevity.

The video on this page demonstrates our crankshaft grinder doing its job. Having this capability in-house allows UCF Machine Shop to provide complete engine rebuilds and testing without added delays.

Hours: Mon - Fri 7:30AM - 5PM