You may be right, I really don't know. This was like the third time I used it. After actually reading the instructions this morning, they make it clear that you should release it down a step before locking at whatever height you go to. I skipped that step.

Others may be touting J&S and B2 models but I will give this one another chance. This jack sits so low compared to others that you can bearly (or not at all) fit under Harley Touring models. My big mistake was placing the pads too far forward and going way too high without reading the f'n manual (rtfm).

 

I have the yellow Sears jack and that happened to me once. I had used it several times before and after with no problem. It acted like it wouldn't go up, to allow the lock to release and I only had it extended about 1/2 way.
I figure it was something I did wrong, because after cussing and messing with it, for several minutes the jack worked fine. I have no idea what I did to get it working again.
Tom

 

Get a jack from a female friend and have her help you "jackitoff".
sorry...couldn't help it.