Contact us

Owlesbury Crankshaft Service
Unit 12 Winnall Valley Road
SO23 0LD

Telephone : 01962 855969
Fax : 01962 856969

Email :

Lower Block

OCS has vast experience in re-boring, repairing and reconditioning the lower block for engines of all types. Our lower block services include re-lining the cylinder block back to standard or to a customer’s specification. We can re-bore V8s on a rollover jig off the main housing diameters to ensure extremely high levels of accuracy and to guarantee all machining is concentric to the mains.

We are also able to re-face and line hone the block to return it to true in order to remove any distortion in the cylinder block itself.

Our lower block services include:

  • Pressure testing
    Pressurising the coolant system identifies leaks and cracks that require repair.
  • Block refacing
    Re-facing cylinder block back to true in the event of damage or distortion.
  • Line honing
    Machining the main cap in order to close the hole then re-machine to manufacturer’s specification removing any distortions or damage back to true.
  • Line boring
    Line boring is a machining process that establishes perfectly straight bores for crankshaft and camshaft housings, our equipment ensures the block housing is remanufactured to true. 

  • Con rod honing
    We machine both connecting faces of the con rod then rehone the bore to ensure it is remanufactured to true.
  • Camshaft bearing fitting
    We remove and refit worn or damaged bearings. We also offer manufacturing of bespoke bearings. We can also line bore the bearings to customer specifications.
  • Small end bush remanufacturing and replacement
    We can remove small end bushes and rebore to ensure all con rods are the correct length.
  • Custom main caps
    We are able to reproduce bespoke main caps to suit any engine or customer specification.
  • White metalling
    We offer reproducing and machining of white metal bearings to suit customer specifications.
  • Diamond cylinder honing
    We use diamond honing to ensure cylinder rebore finishes are within 2 microns.
  • Reliner Motorcycle barrels
    We are able to rebore and fit liners to damaged or worn motorcycle barrels.