Hello Al,
I am in the same situation and was just posting a reply in the Motorhome forum. My system was sitting for sometime before I purchased my 1995 unit that has the HWH series 310 system. My actuators are frozen also and I tried many of the things you have when it came to soaking them in blaster, wd40, brake fluid, etc. Nothing seems to work. They seem complex to take apart and rebuild myself, but I might experiment. I emailed HWH and here is what they responded with.
"If you want to replace the jacks you would order rap7164 for the front and they will cost you $359.10 each plus freight. The rears would take rap7001 and they will cost you $547.05each plus freight. Right now I am out of both these jacks and we are looking at about four weeks before I can ship them.
Now if you want to repair the ones you have it will cost you for the front jacks $251.37 maximum each to repair them and the rear ones would cost you a maximum of $382.94 each plus freight. Now if you decide to send them in for repair you will need what we call an rga#, please do not send them in for repair without that number. The turn around time on these is running about three weeks."
Granted this is for rebuilding the entire jack, but we can also order replacement parts, although the individual parts seemed kind of high and since I don't know if my jacks really work, I am not sure what to do.
Hopefully we'll both learn something new from our posts.
Andrew
