# Ford 3600 Diesel Hydraulic Pump and Selector Valve



## Get-The-Lead-Out.45 (Mar 20, 2018)

I have a 1979-1980 Ford 3600 Diesel with a Dunham Lehr / Farmhand 22 Loader.

The loader worked without any problems what-so-ever when parking it back in November for the Winter months. Now that it's March & had a 55 degree day, I wanted to start up the tractor and get some routine maintenance done on it...but even thou the tractor started right up, nothing happens when I push or pull either spool valve handle for the loader. I tried the selector valve that pulls in and out and is located below the right hand side of the seat which faces the hi/lo shifter but whether it's in or out didn't make a difference....this is the valve that diverts flow from the 3pt arms to the auxiliary flow for the loader, and when it's pushed in my 3pt arms work like they should and when it's pulled out they don't work and so I know that it has to be pulled all they way out or in the middle to divert flow to the loader for it to work.

I disconnected the pressure line at the loader's spool valve and leaving this line connected to the selector valve, I then started the tractor whereby sliding the selector valve in and out to all positions but still no fluid came out the selector valve's pressure line.

I looked all around the under side of the tractor and the ground but there's no leaks. I also removed the small plug on the back right side of the tractor to check the differential fluid and it was full and wasn't milky looking.

Even though the fluid didn't look milky as if there is water in it, Is it possible to get moisture in the hydraulic system and it froze up and won't let the hydraulic fluid circulate through the selector valve and then to the loader's spool valve....or something like that?

Does the external pump on a 3600 need primed and if so, how is it done properly...does a 3600 need to have air blown in through the differential's fill hole located behind the seat on the back right side in order to force fluid up into the external hydraulic pump?


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## RC Wells (Dec 26, 2008)

If the three point functions when the diverter valve is set to that position, then when the diverter valve is set to the loader it fails to expel hydraulic fluid under pressure, the problem will be internal to the diverter valve. 

The internal spool can fail and not transfer pressure to the auxiliary port (loader). Disassembly of the diverter will tell you rather quickly. 

This assumes you cracked the pressure supply line open so a quick connect was not blocking the fluid.


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## sixbales (May 18, 2011)

Howdy Get-The-Lead-Out.45, welcome to the tractor forum.

Other things to check: 1) Quick connect is fully engaged. 2) Quick connect internals are not loose. 3) Hose plugged internally with deteriorated inner lining.

I guess I would disconnect the hose completely off the selector valve and see if you have fluid at the valve. Crank the engine with the kill rod out so you don't make a mess.


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