Walker 780N 10 ton floor jack

[1lineman1]

Was given this jack. Goes up slowly and definitely feels like air is in system oil appears to be low and leaks. But she still lifts a 32gvwr dump truck...so can't complain ! Question, too add fluid and purge air. Just fill in large port on cylinder while lowered then raise and with plug partially cracked? Haven't had too mess with floor Jack's . Also what years were these made? Thanks!

 

[Made in USA]

Parts diagram can be downloaded here (link is under image of seal kit):
https://www.hcrcnow.com/shop/seal-kits/product/1416

Your jack appears to date from late '30s. Check the second page in this ebay listing:
https://www.ebay.com/itm/1939-PAPER-AD-Walker-Greyhound-Hydraulic-Roll-A-Car-Floor-Garage-Jack-Roll-A-Car/152771288250?hash=item2391e0dcba:g:yrIAAOSwCtJZ-5KB

 

[1lineman1]

I was guessing the 60's but that's crazy if it's from the 30's ! Thank you for the link. Turns out it was half empty..filled up and spent about 1/2 hour bleeding. Works perfectly and doesn't leak. Although I think there is a screw missing on fill plug / vent. Anyway there had to be a floor jack guru somewhere right?

 

[nelsonsales]

Im trying to find more details about this jack. I picked up the sane one. Do you have pictures of the back end where the foot lever is?