I have written this elsewhere, but I will try my luck here as well:

We have a 1990 Mercedes T1 208 diesel motorhome. A while back the bracket/mount for the power steering pump snapped off, leaving the vehicle without power steering and unmanageable/unsafe to drive. The bracket/mount was part of the engine block, but there is nowhere to weld/add another bracket to enable the current power steering pump to be powered (by the serpentine belt). As a short-term solution, we installed a shorter belt which bypassed the power steering unit, so the vehicle can still be moved (with difficulty).

We came up with an idea of purchasing a 12 v 200w motor that directly spun the power steering unit (via a flexible shaft coupling). We fitted that in situ with the existing hoses, appropriate wiring and a switch on the dashboard. The motor was powerful enough to spin the pump (quickly), but whenever the steering wheel was turned the motor cuts out. It appears the motor is not powerful enough.

We are now considering an alternative system, utilising a more powerful hydraulic pump unit (e.g. 12 v 1600w unit) that would be connected to the steering box. Our concern though is that a unit such as this may be too powerful.

The existing alternator on the motorhome is either 55A or 80A (based on what someone from Mercedes told me yesterday).

We are considering installing a hydraulic pump in the cabin somewhere, running hydraulic pipes to the steering box, powered by two batteries, that would need to be charged up somehow interchangeably (and preferably while driving). The vehicle already has a leisure battery and a battery-to-battery charger, which are factors to consider. In principle could this work? And, if so, what would be the best hydraulic pump/unit for the job? Are there any issues we have not considered?

Any assistance with this would be much appreciated. It's such a bespoke fix and we're reticent to give up completely. Noone else seems to have had this problem, at least not with the 208D T1