The Stovebolt Site Forums The Parking Lot Big Bolts hydraulic pump

I have a Williams machine co. model 444 ser. # 63497 anybody have info or diagrams. the pump works great but I would like to know more about it for maintenance.

Williams pumps are still made. The only maintenance they really require is to keep the hydraulic oil clean. If you don't have a filter, it would be wise to install one. What is it being used for?

1952 has a huge ram on a dump flat bed

About all you can do is change the hydraulic fluid and add a filter to the return side...not on the pressure side. There are several grades of hydraulic fluid. I would recommend the best grade from a lubricants distributor instead of someone like Walmart.

Williams Machine & Tool - Omaha, NE. originally but was merged into Energy Manufacturing Co, Monticello, IA, which produces hydraulic cylinders for the AG market primarily.

Your pump is a piston design and is probably a 4 piston unit but could be an 8 piston but I don't think so.

In you application a filter isn't going to do much good as it will rarely get used and if it's an old "huge ram" hoist then it is almost certainly of single acting type, hence the oil comes back thru the pressure hose so no return hose is used. Again, this is waht is most likely the case but not carved in stone.
Your valve is probably cable operated and mounts to the top of the oil reservoir.

A word of warning. DO NOT overspeed thsi pump. 1000 RPM is the MAXIMUM it will withstand. Williams pump have a bad habit of coming unwound over that speed. If you tear it up don't even consider rebuilding it, get a remanufacured unit.

thanks for the info. do you think there is a screen in the reservoir ?

Yes, there is a small intake pipe screen that sort of looks like a long bottle cap. It part # 2664. You'll also need to replace the pump gasket if you pull the pump from the reservoir.

One nice thing about piston pumps is that they are bi-rotational so any PTO will work with them. Incidently, your pump is almost surely not original to your hoist as the old underbodies used cast iron gear pumps of 10-18 GPM and the Williams is only 3.7 GPM@1000 RPM. Again, that is the maximum speed so your hoist will operate pretty slowly.

thanks