p/s pump rebuild

[bravekozak]

Since I cannot bench test this pump I bought a tester that must be installed like this. I had to use a 17 and a 19mm wrench to break the M16 X 1.5 flared connector on the high pressure line. I recommend wire wheeling off any rust on the original fittings prior to installing the adapters. The valve must be open when testing. The gauge must be on the pump side of the shut-off valve if the first pressure test of turning the wheels in both directions was out of specification. The second test (only if necessary) of shutting the valve for five seconds or less will allow the pump build maximum pressure.

[bravekozak]

The Mitsubishi pump used in the Festiva looks identical to the one used in the Mitsubishi Lancer. Unfortunately, I can only find the specs for a Mitsubishi Galant pump. I will perform all of the tests listed here and report the results.

[bravekozak]

I got a no pressure condition on the power steering gauge. I took the gauge home and tested it with compressed air. It worked. I am puzzled as to the no pressure condition. I will remove the flow control valve and double check my O-ring replacement. Although I do not think that is the cause.

No power assist after recent P/S system service. This is most commonly caused by fluid contamination causing the pressure bypass valve to stick open resulting in no pump pressure. To fix this remove the flow valve and insure the pressure bypass valve moves freely in and out. There can also be a large amount of air trapped in the system.

[bravekozak]

I just found the spec for a Festiva power steering pump.
1031-1138 psi @ 1000-1500 rpm and 122-140°F.
I didn't need to buy a 2000 psi gauge. 1500 would have been good enough.
I will turn the steering gear slowly back and forth, lock to lock, ten times.

[AlaskaFestivaGuy]

That's quite high pressure for such small parts and minimal fluid volume.

For comparison, the 747 runs at 3,000 psi and the 787 (Dreamliner) runs at 5,000 (allowing smaller lines, less fluid volume, smaller reservoir, all meaning less weight).