51Packard -
Cracking the books is a good first step, but I'm not sure what "Ultramatic service manual" you've downloaded.
Perhaps you are referring to
Section VII - Ultramatic of the
1951-1954 Service Manual. Now, if you'd like to know more about how this automatic transmission works, you may want to review the original
Ultramatic Service Training Manual. However, all that and much more is included in the massive, three-volume,
Complete Ultramatic Service Information for all units produced from 1949-1956. Yet, because bulletin information can be a little difficult to sort through, I further recommend you review the
Ultramatic section of the
1951-54 Service Index.
Eventually, you'll come to find that valve bodies have no pumps or pistons but use sliding-action spool valves to detect various mechanical and hydraulic inputs and respond by directing fluid pressure to specific passages in their bores to perform the desired actions. As such, valve bodies (control valves) are the "brains" of an automatic transmission.
While there ARE two rotary-action pumps used in the Ultramatic, they are mechanically separate from the valve bodies. The front pump is driven by the torque converter and the rear pump is driven by the transmission output shaft.
When disassembling a valve body, NEVER clean the spool valves or their bores with anything abrasive - NOT even with the finest wire brush. Any nick or scratch can cause problems. The valves and bores should only be cleaned with solvent and wiped dry with a clean rag.
When assembling the valve bodies, proper torque of all fasteners is necessary to prevent warping them, which would cause the valves to bind in their bores.
The governors are another important part of the transmission hydraulic control system that should be cleaned. I believe the governor assembly is accessible from outside of the transmission case on your edition of the Ultramatic. Follow the manuals for service, but also check for bulletins on that topic.
Hope this helps.
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