Engine reconditioning & precision machining facility
Crankshaft
Restore worn journals to size and true running geometry. Crankshaft grinding returns main and crankpin journals to specification for use with matching undersize bearings.
What this covers
Overview
Worn, scored or tapered journals wreck bearings and put unwanted load through rods and pistons. Grinding restores each journal's size, roundness, surface finish and — critically — its alignment and stroke geometry.
The crank is inspected, measured and straightened or checked first, then ground to the required undersize so new matching bearings can be fitted. Finish and geometry are verified after every stage.
Reconditioned to measurement
Reconditioned to measurement. Not guesswork.
Decisions on crankshaft grinding are made from recorded measurements against specification — never from how a part “looks”.
Symptoms
These are the problems and symptoms that typically point to the component needing reconditioning work.
Sub-services
Each item is listed so you can see the full scope of this service. Machining jobs run through PRT's inspect, measure, machine and verify route; specialist processes that are arranged externally are called out in the notes.
Crankshaft grinding, polishing, straightening, crack testing and measurement are carried out at PRT's crankshaft stations. Specialist dynamic balancing is arranged externally when required.
Inspection
5 checks and measurements inform the decision to machine — nothing is cut until the component has been assessed.
Measurement & quality
An undersize bearing is only as good as the journal it runs on — size, roundness, surface finish and alignment are all verified.
Verified after machining
PRT process
Journals, fillets, oil holes and the overall condition are assessed.
Journal sizes, run-out and straightness are recorded to plan the grind.
Main and crankpin journals are ground in the correct sequence to the required undersize.
Roundness, size, surface finish and alignment are checked against specification.
Journals are protected against damage in transit and handling.
Machinery & stations
Each operation is carried out at the appropriate station with the correct tooling. The stations involved in this service are:
Gallery
Authentic PRT photography of real jobs will appear here as it is captured and approved.
Crankshaft Grinding work in progress at the PRT facility.
Real photography of the operation will appear here when PRT approves imagery.
Before-and-after records of PRT jobs are published as real projects.
Related services
Restore rod bores, alignment and fastener condition. We check, measure and recondition connecting rods so each rod is straight, correctly sized and ready for the rebuilt assembly.
View serviceStrip, inspect, measure and machine the engine's foundation. We recondition cylinder blocks for rebuilds — cleaning, crack detection, boring and honing, deck surfacing and, where needed, line boring of the main bearing housings.
View serviceA controlled, clean, torque-accurate build. We assemble reconditioned engines from measured components — so the finished unit leaves the shop built to specification and ready to run.
View serviceFAQ
Straight answers to the questions we expect about this service.
Journals are ground to the undersize the rebuild requires, matched to the bearings available for that engine. The required undersize is confirmed from measurement before grinding.
Straightness is checked first and assessed against the crank's specification and condition. Not every crank can be economically or safely straightened — the decision is made from measurement.
Only if measurement shows it is required. Where journals are within specification, the crank is cleaned, inspected and reused as-is.
Get a Quote
Tell us the engine or component, its condition and what the rebuild needs to achieve. We will confirm the scope from an actual assessment.