Did you get a manual with the radio?
I mention the Sabertooth b/c you did and the mix feature is built into the esc itself for plug & play directly to the rx. No further radio programming needed.
In order to MIX valves with the pump, your radio has to have that feature built into the programming to make it work.
Just like you set servo travel, center point, reverse ect for each ch in the menu, there will be a selection titled MIX. Some radios only have two programmable mixes, other radios can have unlimited mixes. You'll need atleast two for this model.
Do you have MIX "ACT" (activated)?
The switch you use to activate the mix, is it turned on?
Did you try changing the -100% with the +100% positions for the Rate?
Do you have the right chs listed for master & slave? (pump is always Slave)
Did you 1st program your esc for it's center point, full on & full reverse positions? What esc are you using?
Read the manual (if you have one) very carefully.
