Swapping 300ZX power steering pumps

By: Jason84NA2T

There are many differences in the early (84-86) and late (87-89) Z31 300ZX's. The power steering pump is one of them, and a concern when swapping engines or doing an upgrade. Weather you are putting an early engine in a late car or a late engine in an early car, the power steering pump must come along with the engine. You can also upgrade your early car with a late pump, which offers much better flow under heavy load. You may or may not have the very common problem of power steering "fade" during heavy repeated use (such as slaloms on an autocross course). I have experienced this with almost every 84-86 car I have driven and it is most likely part of the reason for the revision on the 87-89 pumps.

1. The main problem is the differences in belts.
Z31 Accessory Belt Configuration
84-86 Turbo: 84-86 Non-Turbo: All 87-89 (Turbo and Non):
  • Ribbed belt for Water Pump and Alt
  • V-belt for AC
  • V-belt for Power Steering
  • V-belt Water Pump and Alt
  • V-belt for AC
  • V-belt for Power Steering
  • Ribbed belt for Water Pump and Alt
  • Ribbed belt for AC
  • Ribbed belt for Power Steering

2. Along with the difference in pump shaft diameter and spline; you cannot simply swap the pullys

So to swap the pump from one engine to another, you need to first obtain the correct crank pulley for the pump you wish to use. Only the early 87 cars (with the non-w series engine, before 4/87) use a crank pulley that will fit the 84-86 crank snout and have a ribbed belt for the power steering pump. If you want to install the later pump on an early engine you will need to also swap to that crank pulley. If you are putting a later engine into an early car, this part is obviously already 'done for you' in a manner of speech.

3. The power steering pump mount bracket and the engine lift bracket are pump-specific.

You will need to obtain the correct parts for installation. The late pump can be installed using the early bracket, but not the other way around. The bolt the pump is secured to enters from the front on the later cars, so the pulley is made accordingly. Hopefully examining these pictures will show you everything you need to know.


Power steering pumps and brackets: Left is late ribbed belt style and and right is early v-belt style.


Note the access holes on the late pulley for the bolt that installs from the front.


pump bracket

Power steering pump brackets. Bottom is late and top is early. Note the difference in the way the bolt enters.


engine lift bracket

Engine lift brackets: Left is late and right is early.

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