steve, if these are kick down jacks, you may have rusted pivots. if you can push it down, the actuator is probably good,
soak the pivot bolts at the top of the cylinder with a rust penetrator, or even wd40.
also, spray the actuator with wd40. dont wipe it off. it needs to soak for a while.
let me know if i can help 1 502 549 3638 or
pfmaddox@att.net
if i dont answer, leave a number and a short message. i will call back.
paul maddox
i work full time for hwh corp. i do not sell parts or solicit work on this forum