Hang on man, if the pressure in reverse is zero at 2000rpm, then the pump seems to not be working.
The Convertor drives the pump with those two cut-outs in the hub. When you installed the convertor into the BH, did you remember to engage the pump and the input splines? that would have been TWO convertor-drops.
Then after the Trans was bolted to the engine, do you recall pulling the convertor towards the crank before or while installing the retaining bolts?
If these things are not done, the usual result is a broken pump, and messed up pump-house.
It seems that with the fluid-drop in the pan during the warm-up, the pump was filling the convertor.
But the reverse-pressure at the L/R servo port, says otherwise.
So, Ima gonna have to look at the map; back in a sec
Ok yes this can happen
Let's prove the pump is working.
In reverse, the fluid flow is;
pump to the regulator, to the convertor control valve, to the convertor, to the cooler, then back to the pan. Therefore you can prove the pump is working by cracking the the cooler-line FROM the convertor. Here the pressure might be somewhere between 30 to 75 psi@1600rpm. But you don't actually have to measure it ...... yet. If you have fluid flow, the pump is working.
Now lets go back to the Regulator valve.
Still in reverse; fluid flow is;
from Regulator-valve to the Manual-Valve, to BOTH and simultaneously; the Hi-drum and the L/R servo. Therefore with fluid flow in the cooler line BUT no pressure at the L/R servo, fluid is NOT moving in this circuit or is dumping somewhere.
As to loss of fluid-flow/pressure:
in order of most likely, the choices are;
>failure to synchronizing the manual valve
>broken cast-rings in the Hi-drum
>Fallen out-of-place struts, re the L/R band.
>faulty hi-drum
>broken L/R band
>broken L/R servo
> missing steel check balls at locations 3 or 4
In reverse, NO other circuits in the VB are in any way working.
Here is a pic I snagged off the Net, showing the flow in Third gear. It's all I could find. You'll have to use your imagination for reverse. Reverse is the last circuit on the far right of the Manual-Valve.
In reverse, the Manual-Valve would be all the way to the right, just before the dumping area. Notice that, if stuck between circuits, it would be dumping the fluid straight back into the pan, or attempting to send fluid into one of the other circuits. This is why it has to be synchronized to the gear shifter. and
We use Neutral because in this position, the shifter has a big window with no gating, so you can align the indicator-needle pretty easily. After that, you need to move the selector to LOW, which is the furthest from Neutral, and make sure the trans is indexed correctly, to the shifter. If the indicator-needle is off, it has to be changed, so don't use it as an absolute guide; instead use the trans detent.
If after this, reverse is not in the right place, then you have the wrong external lever-ratio down at the trans. A-bodies are different from all others, until somewhere in the mid/late 70s IIRC, when the factory did away with the bell-crank down-rod.
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