RamTC wrote:
....
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.
Curious material the block is made of.
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I assume this 'cube' swagged in top of inner (black) tube as in Kkellers14k pic. Hopefully Happijac works with you on this