Been a while since I've been here. When I made contact to be a member again I was told it was 22 years ago I was last a member.  I remember getting a lot of help from a lot of guys including OzDozer

Here's my current situation. I have a D2 5U that always stays in a lean-to. I only start it and "play" with it about an hour every summer. Fires up the engine a couple of weeks ago but the arm that activates the hyd pump doesn't want to move. (The short arm at the top of the pump.) I think it's a #44 pump. Am I not activating a control or is the pump seized? I've never had any trouble with it before. 

I have now removed all the linkage, including that short arm, and no rotational movement of that shaft. I don't want to do anything until I figure not what needs attention.  Give me some clues.  Thanks. 

 

Try a little more effort to move the arm. Maybe a heavier mallet tapping back and forth. Put some penetrating oil on the shaft. There's a seal pressed in the casting and water may have passed in rusting or gumming up the shaft. You may want to just service the entire unit. Drain the oil by removing one of the covers on the bottom of the control unit. The ones with two bolts holding them on. There's a magnet on them too that collects metal shaving you can clean as well. Then remove the tank cover and wash out the interior. CAT has a new gasket, oil filter, and the O rings for the drains and filter you can order when you put it back together.

I'm going to do as you suggested, tapping back and forth, add more Kroil. and perhaps get it free. It's been under cover as long as I have owned it.It's been two years since I played with it, but it started quite easily, just no movement with the hydraulics.

Cleaning the pump doesn't seem like too much of a choir except this tractor has been modified and the front radiator guard will require additional work to get to the bolts on the cover.

  I finally got the cover off and need to clean all out.  Figured I'd flush it with diesel. The spool moved (with resistance) only when I tapped it lightly. I gave it a dose of kroil and let it be until I get back to it.  Do I need to remove the spool and clean inside the valve and the spool, or can I remove the cover plate on the side and spray some fluid in there to do some cleaning?  I think the hyd fluid may have been a bit loe and perhaps had something to do with the spool not moving freely.  Any ideas, opinions?  Can I use a gasket maker like Permatex high temp RTV gasket maker instead of the factory gasket?This machine was modified by the guy I got it from.  He added the guard over the front, and it made getting too the hyd, control housing a challenge.

Thanks Neil.  I did get the cover off the housing.  I tried to post a picture of it previously, but I did something incorrectly.  I called Foley Cat this morning and got the gasket on order along with a couple of seals.  The parts man had a little difficulty finding the parts and he had been there 14 years.  I also discovered the volume of fluid should be 3 1/2 gallons.  I appreciate all the help!  Finding information and parts for a 73 year old machine is a challenge.

Good deal on finding gaskets. I have been told none of the make a gasket compounds will compress when the get in the hydraulic pump so stay away. And very hard to get just enough and not have pieces that break loose only to get caught in places you don't want them.

You got it down this far. So, I would pull the whole unit looking at the crap laying in the bottom of the tank and rust on the top of the spool.
Not that big a job. PIA removing the 4 nuts in the center between the grill and #44. Once you have it pulled you can clean everything better and get rid of the rust.
Also have a look at the spline on you pump shaft and the female coupling. I've had couplings that there is little or not much left of the internal spines left.
The pump shaft is hardened but the coupling is soft metal. I've changed a few by removing the old coupling ,cleanup in the lathe and weld a new one on.
This may be more than you want or need to do because you have to remove the radiator to work in the pump driveshaft. Glad you found the seal for the operating lever.
I had trouble last year finding a OEM one. Now I can't remember if I found OEM for the pump cartridge but there's two piggy backed in there.