Happijac lubrication

jjintax: The popping sound you heard in the jack was the friction clutch balls moving in their seat. This clutch is part of the gear head assembly. There is a circular spring that hold three balls that sit in a depression on the clutch gear. The tension on these balls is determined by the pressure created by the shake proof nut holding the circular spring and balls on the gear. See photos. When the jack screw becomes dry and stiff, more torque is required in the gear train and the balls click in the clutch. Initially I wasn't sure how to set the tension on the shake proof nut, so I measured the distance with a micrometer to approximate the torque setting on the spring. See photos. Subsequently, I learned from HJ tech support that there is a torque setting for this nut. I can't remember what it is right now, I'll need to check my notes and see if I can follow up (I think it was around 9 inch/pounds)(Edit: I checked my notes and HJ tech support said to use 9-10 inch/pounds on this nut). Using the distance measurement method worked pretty good. I needed to increase the torque on one jack after I assembled it.

Gear Assembly


Clutch, showing balls on gear drive


Clutch, gear nut setting with a micrometer- better yet, use 9 10- inch/pounds of torque on this nut