350 utility diesel hydraulic problems

Well I have an old 1957 International 350 Utility Diesel. And here is a little history. This tractor sat in the weather for 5yrs because of a fuel leak. I purchased it and towed it home
and found the fuel pump was bad so I removed the pump and injectors and had them rebuilt. The tractor runs fine now although the hydraulic system started working rather odd. At first the power steering and loader/3 point worked great. When the problem began with the hydraulics the loader and 3 point started operated slowly. Then in order for the loader or 3 point to work you had to turn the steering right or left, shortly after that it lost both power steering and all hydraulics. So I took the tractor to a tractor repair shop. There they had ask too run a series of tests to rule out the pump. So 2 wks and $300 later they said it was the pump. Well I purchased another pump and installed it. It is now doing almost the same thing as before when it started acting up the first time. Now the loader and 3 point go up nice and smooth but now it doesn’t have power steering, oh and you still have to turn the steering wheel right or left to get the loader and 3 point to function. The pump is making a noise as if it is low on fluid or if you turn the steering wheel full turn.

So without hooking up a pressure gauge I removed the high pressure line from the steering assembly and it seemed to have plenty of pressure. Then I removed the return line from the power steering assembly to the reservoir and it seemed to have plenty of pressure there as well. So nothing seemed to be plugged for the power steering loop. I only ran the tractor long enough to make a quick check because I noticed the pump was getting hot. In the trouble shooting section of the manual it leans towards the FLOW CONTROL VALVE ASSEMBLY. Well it was removed and checked for debris and rough spots. The spring was replaced. At this point I need some help in trying to diagnose the problem. I have multiple pictures for a visual aid. All of your responses will be greatly appreciated. You can also email at bprice@mc3corp.com

Thanks, Brian

Thanks, Brian

So I tightened everything up, added fluid and started the tractor. It now seems to have power steering and front and rear hydraulics. Although the pump still seams to be running hot. I had also noticed that the O ring seals @ the pump/manifold started to leak a little. I will replace them with new ones and see how things continue to work. I believe I should still remove the resevoir and check the condition of the screen. It's too bad I got taken for $300.00, guess I'll know better next time. I'll respond as I continue with this ol relic!

I'm not positive this is your problem, But I tried EVERYTHING to fix my whining pump except for this.

While you have the hydraulic oil out, either change it with new, or filter the old stuff good before u put it back in. If its milky or cloudy it has moisture in it and will need to be replaced or heated up and the water driven out of it, not too hot or u can burn the oil. (not much above 220F outta boil the water and not harm the oil)

Cleaning the filter isnt a simple process, so try to see if you can see it through that cap. If you have gasket material, u can make a new gasket, which I've done, not the easiest, but I've done it. They are only 17$ at case, so maybe that would be the better route. Just be sure not to crush the filter or you'll be shelling out around $90 for a new one, like I did. Just loosen the nut holding the fiilter on the res cover, and then spin the pipe off using channel locks or something, best to replace the oring while your at it, so its not sucking air.

As I said before, I'm not sure if this is the problem, but if your new pump is also whining, the filter is probably at fault. I did everything to my system before I took that route. I boiled and filtered the oil 3 times because of the residue in the hoses and cylinders would recontaminate the fluid. Then I changed the fluid. I diassembled/inspected/cleaned both of my valves and the safety regulator. Still a whiney pump. I narrowed it down to a clogged filter or worn pump drive gear. I took the res cover off, the filter was clogged and had crushed the filter and sucked a hole through it. I didnt wanna spend the $90 on a new one, So I went the cheap and stupid route and put an external filter assembly on the hardlines. While this was a good idea in theory, these older pumps are not designed to suck fluid through a 25micron hydraulic filter, especially in the winter. removed the new filtr asembly, and no whine. Just got a new OEM screen, and am about to put it back in. If yours is damaged, I suggest u try to find a used one (good luck, I looked for over a month), or you'll have to spend the money on a new one from the dealer.

Hopefully Your is in good shape!!
Good luck.