Finally you will want to do what we feel is the most important step, WPC treatment of the rotor gears, pressure relief valve piston and the housings, including the pressure relief valve bore. WPC treatment dimples the surface on a microscopic level to help maintain a good oil film for better lubrication. It also creates a hard and smooth surface that is very slick and silky. This goes a long way towards reducing friction and eliminating galling. This smoothness will reduce oil temperature and make the pump more efficient. It also further deburrs the parts.
|Our oil pump after WPC treatment. We WPC treated the gears, pump housings, oil pressure relief valve and valve bore. WPC uses a different treatment on the gears to impart more fatigue strength and lubricity than the softer aluminum housing. It’s hard to see in pictures but the treatment leaves a silky smooth and slick surface. All edges on the inlet and outlet ports are chamfered and edges broken. Our pump is ready to be assembled and rock. Be sure to use assembly lube on the pump when putting it back together. This helps speed its priming and prevents galling when the pump is turned with no oil for the first time.
Most importantly WPC will strengthen and surface harden the rotor gears and greatly improve their fatigue strength. This will make them more resistant to breaking under harmonic stress. To read in detail how WPC works, check here! WPC is not snake oil and is highly effective in applications like this.
When reassembling the oil pump it is best to pre lubricate it with assembly lube or thick oil. At this time you can shim the oil pressure relief valve spring 2-3mm. This will increase the peak oil pressure by 2-5 psi although we usually don’t do this on most motors. This only increases the peak oil pressure not volume so it will only increase pressure at best at high RPM. A case where we might do this is on an engine with intentionally loose bearing clearances.
Hopefully this info will help you when preparing a high performance engine. Remember, don’t neglect the oil pump any more than you would overlook your own heart.