I understand but unless you are stressing your BH for hours at a time heat build up is just not an issue. If you are using the BH that aggressively then IMO you should have a dedicated BH or mini excavator.
Actually, Ed, it is not an aggressive or excessive use of a CUT backhoe
attachment to just do some trenches for several hours at a time. I have
done hundreds of feet of trench over the years, but that is not my
primary use. The oil gets very warm using the hoe steadily for an hour or
more. Too warm? Maybe not. I think many CUT hoe users will want to do
some long trenches or big holes.
For my own tasks, I rarely operate the hoe for hours at a time, so the
work port power approach is not a problem. But in setting up a hoe for
a tractor from scratch, I think it is important to know the best ways of
doing it and the tradeoffs you make. And, if you are starting from scratch,
it may be no extra effort to do it the best possible way.
I like to learn by trying things myself or seeing first hand how the different
approaches work. I think it is important to mention another plumbing
approach here. That is, the approach used on my B21, which is also used on
other TLBs. What they do there is provide a driver-accessible manual
diverter valve that switches the hoe loop in and out of the power beyond
circuit downstream of the FEL valve, without having any QD fittings in
the circuit except when the hoe is attached. This is probably the
ideal setup.