IH 574 3-Point Hitch Problem

[jpbmass]

The 3-point hitch on my gas IH 574 has become erratic. I have a brush hog attached and it seems there is little or no hydraulic power to the hitch unless I activate the front end loader (lift, lower or tilt -- all loader actions make the 3 point hitch work normally!). If I set the mower at the correct level I have to touch the loader controls a bit every minute or two to keep the mower leveled. Everything else seems to work -- PTO, brakes, Pwr steering and Front Loader. When this system is cold, the hitch sort of operates (without activating the loader) hesitantly and slowly. Does anybody know what's causing this and how to fix the problem?

 

[JimB2]

How is the FEL connected, with a separate loader valves and then to the remote outlets at the rear of the tractor or plumbed into a power beyond port or some other plumbing method? Is there any buzzing noises from the hydraulics?
To me it would appear for some reason the FEL is starving the 3PT of high pressure hydraulic oil.

 

[jpbmass]

FEL has a separate loader valve assembly that is "fed" by two large neoprene hoses. One hose goes to the area where the hitch and pto levers are (the Multiple Control Valve assembly?) and the second goes under the tractor back by the 3 point hitch. The current operation of the 3pt hitch feels like the hitch is starved of high pressure hydraulic oil until the FEL is used (when I raise or lower the FEL, the 3PT hitch simultaneously works) - as soon as the FEL stops moving, the 3pt hitch stops working. This all has worked well for many years; it just recently became a problem.

 

[JimB2]

The MCV is behind the Hydraulic filter under the rear of left footrest. How is hydraulic fluid level? Has hydraulic filter been changed recently?
If the tractor has Remote hydraulic outlets at the rear, does the 3PT work after you pull the Remote hydraulic lever and dead head the hydraulic system?

 

[International454]

Have you checked oil level?
Have you changed filter lately?
Is oil radiator clean

 

[jpbmass]

The hydraulic fluid level is full and appears clear; it has not been changed in a while, but all other functions are working well. The tractor does have remote hydraulic outlets at the rear; I think the control for that is a 3 position control lever just under the 3pt levers? As I move this control through its 3 positions, the 3pt operates the same. Some good news, however -- the 3pt appears to be getting back to normal. Maybe some valve somewhere was temporarily clogged or stuck and is self-healing. I'll be mowing the second half of my 8 acre field next week and will stress test it then. The 3 pt is still a bit sluggish, but seems to be working.

 

[BarnyardEngineering]

You're probably not going to get an "adjust it away with the twist of a screwdriver" solution. This is one of those frustrating problems that's a mystery because few people have an intimate knowledge of this series tractor's hydraulic system. It's magic. Heck you may pull everything apart, and find nothing wrong because the fleck of crud that was causing it fell out when you weren't looking, and you'll never know why...

Just with a basic understanding of hydraulics, though, it sounds like a priority valve somewhere in the system is not prioritizing, so you have to "deadhead" the system by working the loader to get pressure to the hitch. (Quickest way to do that BTW is to simply roll the bucket back if you haven't already figured it out. It's already rolled back so it will immediately deadhead the system and you won't have to dink around raising and lowering the arms.)

I call it a "priority" valve but it may not actually be that. I assume some flow is diverted to the 3pt as needed.

 

[JimB2]

Most likely the Flow Divider valve sticking in the bore in the MCV located behind the hydraulic filter. Dad had that problem many years ago on his new IH 454 (3 cyl version of 574), IH mechanic changed the flow divider with the newer cartridge style fix it. Pulling the Remote valve lever dead heading the hydraulics usually unsticks it for a time.

 

[used red MN]

Pulling the Remote valve lever dead heading the hydraulics usually unsticks it for a time.

The tractor does have remote hydraulic outlets at the rear; I think the control for that is a 3 position control lever just under the 3pt levers? As I move this control through its 3 positions, the 3pt operates the same.

Not sure if you understand the terminology used here but by moving the remote lever through the positions assuming you have nothing connected to the rear remotes this is what you did. You dead-headed the remotes, which means you put pressure to them but it was “dead-headed” or forced to a dead-end, it had nowhere to go so the hydraulic over pressure relief valve opened to spill the pressure internally back to the reservoir.

 

[jpbmass]

It does seem a bit like magic but is is working better. There are so few mechanics around that will touch an old tractor -- it is comforting to know that you folks are willing to share your knowledge.