Ok, so I've come to the conclusion that there is probably an obstruction at the steering gear, hopefully where the high pressure side connects to the gearbox but who knows.

I came to this conclusion based on the fact that if you reverse pump direction briefly it relieves the obstruction, which reappears after about a quarter normal revolution of the pump pulley.

I'm going to first pull the high pressure line and check the orifice at the gearbox and then pull the return line and use compressed air to reverse fluid flow out through the steering gear. Finally, I'll detach the high side from the pump and drain / clean the hose out.

I can't imagine what got in there but certainly something did. If this fails to resolve the problem I'll have to move to plan B, which entails swapping the steering box itself, which means another trip to the salvage yard.

Any other advice or recommendations?

Steve A

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Steve A
92 W140 OM603
97 VW Jetta TDI
90 Passat variant TDI 6 speed MT
94 Chevy K1500 6.5TD
05 E320 CDI
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