Then I cracked the valve, just enough to apply a few PSI if air pressure to the tank. Once the fuel started running out of the top of the PT pump, I shut the air off and reinstalled the pipe plug. The truck then started right up with no issues! Once I was confident my air bound issue was solved, I took the truck for another few test rides and realized I had another problem. At idle or just off idle the truck was very difficult to steer, as if the steering was bound or the power steering wasn’t working. At first I thought 500 rpm was too low of idle setting so I made a tool to adjust the idle with a brass fitting and an old screwdriver. In the meantime a friend of mine also have me the screwdriver tool he made years ago...

I turned the idle up to 650 and it didn’t help at all. After talking to Stan A was well as the guys on the JustOldTrucks message board (especially Tony B.), I realized my issue may be the power steering pump.
If you remember correctly I had bought a pump off of eBay to replace the original one I had. The only difference between the 2 was that the new one was rated at 1250psi and the original one was rated at 1500psi. At that time all I thought I had to do was replace the spring in the valve to increase the pressure from 1250 to 1500. So at that point I thought I had either a pressure or flow problem...
I know this part will get in the weeds a bit, but I figured I would share it here just in case it might help someone else. For reference, the correct part number for the pump was V20F 1P8P 38C 6F 11, where the 8 means in ‘1P8P’ means 8gpm at 1200rpm. That correlates to 3.33gpm at 500rpm (idle). According to Sheppard’s literature, the minimum flow for their 592 steering box is 5.7gpm. But more than likely, the flow ratings given in the Sheppard specs are for the flow control valve setting not the minimum pump output at idle.

At this point I started doing some research on what Vickers pumps were used on other Brockways. A few guys on FB went out of their way to get the numbers off of their pumps and I was able to put this list together...
V20F 1P8P 3C 6F 11 - This appears to be the correct number for a pump on an 855 Cummins.
V20F 1P9P 3C 6F 11L - This appears to be the correct number for a pump on a 671 Detroit. Left hand
So it looks like the Detroit has one more gpm at 1200 rpm (8 verses 9) and is left hand rotation.
Regardless, Joe D had a parts 671 Detroit motor and let me borrow the pump off of it.

I removed the valve and spring from this pump and cleaned it up. At that point it dawned on me that when I swapped the valve over from the pump I bought on eBay, I used the wrong valve body. The valve body and the orifice are slightly different. In fact the 1500psi valve has ‘15’ penciled on it with a scribe. So in reality I only had 1250psi of pressure when I needed 1500psi...

I was able to remove the pump from the back of the oil pump without disconnecting the lines. I was also able to remove and replace the flow control valve and spring without losing too much oil. A half hour later I was able to drive the truck out of the garage, and easily turn the steering wheel with only one hand!!!
The following weekend Russ called and asked if he could stop by and visit. Once I hung up the phone I pulled the truck out of the garage and warmed it up. Right after Russ showed up we went for short ride around Daleville...

I did take the truck to our Harford show and put a few miles on it driving it locally. Tommy and I also took it for a nice ride, right before the snow we got last week...
https://youtu.be/HrM8h-f_-CISo that’s it for now!!!
Tom