Aloha, on our 45 sit-down electric, we rebuilt the tilt cylinders and now the forks will not go all the way down. Forks go up and down when engaging the side cylinders, but as soon as it comes down to compress the center cylinder, it stops.
1) there is nothing bent or obstructing the tracks.
2) rollers, etc. are in good condition
3) center cylinder will compress if there is a large weight on the forks, but not when empty.

***BTW should the pump motor be engaged on when lowering?***