Chase Bays - Chase Bays Cylinder Head Oil Drain Kit - Nissan RB20 | RB25 | RB26

A very common issue with the Nissan RB Series engines is the over-oiling of the cylinder head. This is such an excessive problem that it pushes out of the valve covers, into the PCV system, into catch cans if you have them...which then cause a slew of other issues like oil in your charge piping and of course oil all over your engine bay. We designed this product to fully bolt on to easily keep that excess oil drained back to the oil pan, all in existing locations...no fabrication needed.

There is a freeze plug on the back of the cylinder head that you can hit the inside edge of with a flat head screwdriver, then pull out, and add on our Billet 6061 aluminum 10AN Cylinder Head Oil Drain Flange, anodized signature Chase Bays Semi-Gloss Black of course. It is secured to an existing threaded hole on the back of the cylinder head with an M6 allen. We include a premade 10AN Hose, all BMRS of course, that routes along the block, under the engine mount, then into the RB block with our 3/4 BSPT to 10AN adapter. Both the cylinder head flange and 10AN to BSPT adapter are class 3A Mil-Spec threads.

For those concerned with the hose going lower than the drain, we already thought this through. With normal healthy crankcase pressure that occurs, even with a proper catch can, plus the amount of oil  flow - it will not back up and will consistently drain down. We balanced out routing that avoided heat and various turbo setups and found this was the best solution.