I have this mixer and currently when the effects loop is activated, the effect is only partially mixed with the signal. I want it to be 100%. Either fully on or fully off when bypassed.

No, the mixer does not have any wet/dry or efx mix controls.

I have attached a schematic. (The mixer has two sets of sends and returns. One is able to be switched on and off while the other is on all the time if something is plugged into it.)

I was wondering if the Z7 section in the top right has anything to do with this and if it can be bypassed to achieve 100% effect.

Thanks

 

I was not able to follow the effects return back into the string. I think that is on a different sheet. The whole thing is a bit complicated, and the circuit drawing is quite compressed.
The process for locating the point to open so that all of the signal passes thru the external effects will be to trace the circuit from the amplifier stage that feeds the effects out jack and follow the other branch to where it sums with the effects in jack signal. THAT is where the "non-effected" signal joins the "effected" signal. Wet and Dry are simple to use but a bit confusing for some of us.