HappiJac 4150 Problem
So much for "HappiJac's Acme Screw Jack is the first acme screw jack with a redundant safety check system" One of my rear jacks failed, has no ability to raise/lower or hold up the camper, just sli...
Forum Discussion
I reviewed those pics before posting, but thanks. It sure seems like the worm gear top assy has failed as I see nothing else that would allow the jack to retract itself back under load (without any shaft rotation). I'll take apart and see, but IMO this is a big time design failure.
Update: It took all of 10 mins for me to disassemble the jack. The failure is as I suspected, the crimped in worm gear threaded assy block that is part of the lower tube has failed in a way that allows the long threaded shaft to slide through under load. I suspect the threads are deteriorated due to moisture. This means that all my Happijacs are subject to failure at any time. They were new in 2005 and oiled as suggested by HJ. I'll contact HJ to see if I can just send them in the lower tube and I'll pay for the repair.
Update: It took all of 10 mins for me to disassemble the jack. The failure is as I suspected, the crimped in worm gear threaded assy block that is part of the lower tube has failed in a way that allows the long threaded shaft to slide through under load. I suspect the threads are deteriorated due to moisture. This means that all my Happijacs are subject to failure at any time. They were new in 2005 and oiled as suggested by HJ. I'll contact HJ to see if I can just send them in the lower tube and I'll pay for the repair.
