Hi all, just install a engine in a 90 toyota 3vze, motor works awesome but the clutch is not ingaging, slave clylinder looks to be extended, clutch is really soft,

 

so by not engaged, you mean there is no drive, even with the clutch pedal out? Probably air in the lines. Bleed system per instructions in a service manual.

 

or you installed the clutch disc backwards! Oops!

Did you disconnect any of the hydraulics of the clutch when removing or installing the engine? If not, you may have lost a master cylinder, or installed the disc backwards.

 

I'm also struggling with this same issue, so any help would be much appreciated. The only difference is mine is a 22re, and the donor motor had the existing clutch already installed, so I just decided to use it.