CHRA & Bearing Kits

Rebuild kits renew the centre section of a turbocharger, where the shaft spins on its bearings between the hot and cold wheels. Repair kits restore the standard parts, while upgrade kits add a stronger thrust bearing, better seals or a billet compressor wheel. The section also holds single wheels, actuators and parts for variable-geometry turbos.

In a journal bearing turbo, the shaft runs on a film of oil inside plain bearing bushes; a ball bearing turbo carries it in a cartridge of ball bearings. A thrust bearing takes the end load, which changes with the pressures acting on the two wheels. The piston-ring seals at each end are not tight lip seals, so a blocked drain or high crankcase pressure pushes oil past even good ones.

Typical signs of wear are shaft play beyond the maker’s limits, rub marks from a wheel, oil leaking into the intake or exhaust, and a new siren-like noise. Start from the turbo or engine named in the title, then choose the type of kit:

• Repair kits: bearings, thrust parts and seals to restore a standard turbo.
• Upgrade kits: a 360° thrust bearing, with a full ring of bearing surface for more load capacity, an upgraded oil seal or a billet compressor wheel.
• Ball bearing kits: for ball bearing turbos, listed by turbo generation.
• Variable-geometry parts: vanes, nozzles and unison rings, including 13.2 mm vanes, for turbos whose vane mechanism has worn or stuck with soot.
• Two-stage systems: separate high side and low side kits, so check which stage you are rebuilding.
• Single parts: turbine wheels, cast or billet compressor wheels, a 60/80 mm billet wheel, stamped actuators, a larger backplate and an intake tube kit.

Rebuilding needs a clean bench and a dial gauge to measure end and radial play. Once a wheel or shaft has changed, the rotating assembly must be balanced, so leave that step to a turbo specialist if you lack the equipment. Find out why the turbo failed before it goes back, whether oil starvation, dirty oil, a restricted drain or debris. Fit a clean feed line, change the oil and filter, and prime the centre section with oil before the first start.