Need info on Hydrostatic system

[OTHill]

Hi! I have hydraulic components taken off an 855 MF swather. I want to build a mini dozer modeled somewhat after a D4 cat.Can someone help with specs please? Front pump is Cessna 70444LAB 2C47 GLF. the rear one is 70444LAG 2E46GLF. Motors are Cessna 74418DAV I can't find info anywhere. Seems Cessna was bought out by Eaton sometime ago. I need to know pump and motor cu.in. ratings to start with. The motors did drive through 26:1 planetarys which I have also but I think will be to big for my project. Price was right free for removing! I have a 3 cyl. 20 hp. Kubota engine I want to use. Total machine weight possibly 800 lb? I realize the hydraulics were driven by at least a 125 hp. engine in the swather but it also weighed 4 to 5000 lbs. I'm thinking of running the pump around 1000 RPM which is 1/2 engine speed. I know the 2 big ports on each pump went to a hydraulic wheel motor the other pump ports are case drains? The pump on the end is a charge pump? Just wondering what the working principle of this system is? Thanks in advance.

 

[RickB]

A service manual for the swather might answer most, if not all of your questions.

 

[oldnslo]

From memory I believe the pumps & motors are around 40 cc but not 100% positive.

Also Don稚 remember exactly but believe rated for around 3,000 PSI

 

[OTHill]

Thanks for replys! Maybe some more will chime in with more info.

 

[OTHill]

Any more info anyone. I can't find anything

 

[dstig1]

If Eaton bought them, they are pretty good about maintaining obsolete manuals, IIRC. Check the website and search on the model number. It might be Parker i am thinking of, not Eaton...not sure but worth checking.

 

[wdchyd]

http://www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/pll_1508.pdf

 

[wdchyd]

The two front piston pumps are 1.24 in per rev. Built in geroler section for charge.
The rear pump is a standard gear pump config with a built in priority valve flow control. Not used for drive but for aux hydraulics.

 

[wdchyd]

https://www.eaton.com/ecm/groups/public/@pub/@eaton/@hyd/documents/content/pll_2221.pdf

 

[OTHill]

Thanks wdchyd that gives me mostly what I need. Just wondering what the ports are for and how the oil flows?

 

[wdchyd]

So it looks like I was wrong about a built-in geroler, that model has no geroler and uses charge pressure from an outside source (likely from port#6) and plumbed in to #2 and #3. #1 is definitely case drain, #5 is suction from reservoir, #6 priority flow to charge ports. #4 to aux circuits (lift cyls, tool circuits?)

 

[oldnslo]

The pumps listed are 70444 while the parts breakdown posted by wdchd shows 70144. Which number is correct?

Messisks has a parts breakdown of 70444-RAU which shows it being 40.64 cc.

I cannot find any other document showing model code breakdown for the 70444 series

 

[OTHill]

The 70444 is right so it looks like pump disp. is 40.64. Now for motor disp. I have looked all over and found lots of used ones available but no specs anywhere. Motor #744418 Cessna or Case D74973 interchanges with Cessna. Thanks for the help so far.

 

[wdchyd]

Oh My, sorry......I need better reading glasses, my apologies

I’ll need a slice of humble pie later 2day....

 

[OTHill]

No problem. The fact is if I had paid more attention when I took this all apart I wouldnt have to be asking what all the ports are for.

 

[slowzuki]

Nice, I've been looking for one of those motors for months now. They cross to a new Eaton 74318DAP 40.6 cc motor I believe and you would want to sit down when you get the price at a dealer.