IH Hydraulic System Info

[IH_4_Me]

Hey guys,
Just a few querys about the International Harvester hydraulic system.

Question Part 1:

What type is it, is it different from other makes?
I ask this because my tractor (IH 574) has 3 hyd hoses running to the FEL control bank, whereas the tractor we have at work (JD 1640) has only 2, a pressure one and a return one, a very simple system. Both FEL's are identical but for the control bank. What is the reason for an extra hose on the Inter? The only reason I can think of is that it has a different hydraulic system than the John Deere.

Question Part 2:

Is there a way I can convert it to only having 2 hoses? Also, when I take the loader off, the tractor makes a whining noise from somewhere under the seat, exactly like the noise it makes when you extend a hyd ram to its full stroke and it won't go any further. Any ideas?

Thanks for your help as these things are bugging me! /forums/images/graemlins/smile.gif

 

[nailerguy]

IH, In your post you say that when you remove the loader, there is a noise under the seat that sounds like the loader is stalled. That sounds to me like the hydraulic system is bypassing across the pressure relief. /forums/images/graemlins/frown.gif This is very bad! I hope you are not running the tractor like this. If the oil is going through the pressure relief, it will heat up in a matter of minutes!/forums/images/graemlins/blush.gif

For example, I build hydraulic power units and sometimes need to test the reaction time of different hydraulic valves at different temperatures. One of the fastest ways to heat the oil is to run it through the pressure relief under pressure. At 1600 PSI pump pressure, a 34 GPM pump will heat 60 gallons of oil from 40 degrees to 135 degrees in 15 minutes or less. /forums/images/graemlins/shocked.gif

This is a lot more oil than what is in your tractor, it is also alot more flow, but the results will be the same. The longer you use it the hotter it will get until something fails from the heat.

Was your loader made to be removable? or was it modified? If the tractor has a fixed displacement pump for the loader and it was made to be removed, there has to be a bypass that diverts the oil back into the tractor case under no pressure when you disconnect the loader, (maybe the purpose of the 3rd hose).

I dont know your tractor, but I do know a little about hydraulic systems, hopefully someone who does know your tractor will clear up the meaning of the 3rd hose from the control valve for us. Aside from that, have you considered calling a dealer and talking to a service rep? It may be worth a shot, but in any case, I would advise that you dont run the tractor without the loader until you find out for sure.

Good Luck and keep us posted/forums/images/graemlins/cool.gif
Nailerguy

 

[IH_4_Me]

Hey there,
Thanks for your post,
I think I am making some headway. It seems to me that the loader has been put in series with the other hydraulics of the tractor. It looks like there is a pressure hose which has been disconnected off the pump and connected to the loader IN hose. Then there is a second hose from the loader that goes back to the pipe on the tractor that has been disconnected. The third hose is a return back to the sump. This probably sounds confusing so I've drwn I simple diagram and attached it to this post.
This means that as soon as you disconnect the loader the hydraulic oil has no where to go!!

 

[jd110]

When you remove the loader, you will need to reconnect the pressure line to the rest of your hydraulic system. That will allow the other functions to work and will prevent the system from running in relief. The international uses an open center hydraulic system. This means that oil is always flowing in the system, but only builds pressure on demand. The John Deere uses a closed center system. At least most do. The 1640 is not a model I am very familiar with since it wasn't sold in U.S. when new. Closed center systems have no flow until there is demand, but they always have system pressure of around 2300 psi. It uses a more sophisticated pump and is generally considered to be a more responsive hydraulic system since pressure is always available instantly. It is not neccasary to reconnect the lines when unhooking an attachment. Just cap off the lines. In fact, on a closed center system, if the lines are reconnected and fluid is allowed to flow freely, the system will overheat. I hope I didn't confuse you further.

 

[IH_4_Me]

Thanks jd110 for your reply, it's just what I was after, and no it didn't confuse me anymore.. /forums/images/graemlins/laugh.gif I do agree with you that the John Deere Closed Centre hydraulic system is much better, it's so simple to use and understand. This was my first encounter with an IH hydraulic system and I thought it would be similar, hence my original confusion and much time spent scratching my head wondering what on earth was wrong!
I just have to get some quick-connector couplings now so I can join the hoses up when the loader is not in use.

Thanks again,
Glenn