4905 parts book?

[DonH4106]

Does anyone have a parts number for the steering gear pump for a GM 4905? That is where my steering gear came from on our 4106.
The pump that is on the 8-71T is a Vickers ATM-42. This pump may be a mis-match for the Sheppard steering box. Anyway I will be installing a new pump and I would like it to match. The pressure relief valve on the ATM-42 dumps at 1750 psi and the manual for the Sheppard box requires operating pressure of 2000 psi. Maybe I am shooting into the dark but I have to solve my steering problem.
Don

[wildbob24]

Don,

The part number 2030977.

However, the operating pressure of the 4905 system is 1450-1550psi with the relief valve opening at 1500psi(+ or - 50psi). This from the 4905 manual as well as the Sheppard conversion for GMs manual that Gary Dean put together many years ago.

Bob

[DonH4106]

Thanks Bob
That information also helps. My 8V71T came from a Grummon Flxible transit so I do not know what the rating of the pump is(Vickers ATM-42). I do know it is not putting out much pressure. Sheppard manual shows a test tool that I might have to invest in. It is for testing pressure and flow. The max pressure is 2175 psi not operating pressure. First I will look into replacing the pump.
Don

[luvrbus]

If the pump is off a Gurmun/Flx it is 2000 max psi at 2300 rpm and the relief valve setting is 1700 psi according to the book, maybe not enough oil flow it is a 5 gpm flow and 4 gpm controlled flow pump I don't know what the GM's require 

[wildbob24]

The GM is spec'd at 3.5gpm minimum to 4.5m maximum. Before I replaced the pump, I would pull the relief valve and check for trash or a weak spring. You should be able to do that without removing the pump.

Bob