touch control getting hot and whining

[bobburke]

My 74 cub touch control block is making a whining noise that stops when the levers is moved. Also the lines and block get hot very quickly. I searched the issue and comments were made about a clogged filter orifice. I pulled the tank and dashboard to look for a screwdriver plug but mine has all hex head bolts and a 1/4" square plug. I know I should just rebuild tc block but what to get it working to see what else needs repair and tackle it this winter.
I rebuilt hydro pump and bled the system already

[cubbrian]

Access to the orifice is behind the "head" of the touch control. I believe it is a slotted fitting about 1/8" in diameter.

[Dale Finch]

The screen is behind a plug on the rear of the block. You do not have to remove the head to access it.
Depending on which TC block you have (by block part #), these rebuild HOW TO's should help you identify it.
New style:
http://farmallcub.com/phpBB2/viewtopic.php?f=141&t=42857
Old style:
http://farmallcub.com/phpBB2/viewtopic.php?f=141&t=89514

You didn't change any of the limits where the touch control rod attaches, did you?
And did you make sure the block is full, and with the fill plug out, you have run the TC lever back and forth multiple times to bleed the system?

[bobburke]

Funny you should mention the rod. The rod when I bought it was all bent and looked to be welded . It would only allow the lever to move half swing and hit the bell housing . I replaced it with a spare I had and seems to run the whole length of travel but still whines like it did before. Didn't seem like there were any sort of limits and the noise is the same at any point I stop the lever. I will look at the links and just order rebuild kit

[Glen]

Hi,
You have to remove a plug on the Touch Control head to get to the orifice, the orifice is behind the plug.
The plug might have an allen or square head.
Below is a pic from TM Tractor showing the plug, it is less than half way up the head, and on the left some.
The 2nd pic shows where the orifice is, the head is off the Touch Control in that pic.
Use a screwdriver that fits the slot in the orifice well, grind a screwdriver to fit, if needed.

A 1974 Cub would have originally had the newer part number Touch Control, 360719R1.
The block part number may be inside the front of the block, near the piston.
Many years of Touch Controls had the number on the left side, but IH changed the number location in the later years of Cubs.
The 3rd pic shows it, you can see part of the number in the pic. Use a light to find the number, if you need it.

The strainer might be dirty, if the unit is getting too hot, slowing the fluid flow, just a guess.
You can see the end of the strainer in the 2nd pic, it is in the lower right hole.
You have to remove the head to pull the strainer out.
It can be cleaned by removing the bottom cover from the unit, but not replaced from the bottom.

Below is a listing at TM Tractor for a new strainer, you can look at the pic to see what it is.

http://www.tmtractor.com/new/hy/918fp.htm

Sometimes the screen breaks on the strainer from being old, then there is little or no filtering.
The strainer in yours might be good, and just need cleaning.
But, if you rebuild the unit, it would be good to put in a new strainer.

The Cub operator's manual says fill the unit the last time with the arms in the rear or down position, after removing the air from the system.
The fluid rises in the system as the arms go to the rear position, so it will be overfilled if you fill it with the arms ahead.

Below is TM Tractor's page of Touch Control parts.

http://www.tmtractor.com/new/hy/hy_001newparts.htm

[bobburke]

Thanks Mine was a 1/4" square plug. I was able to get the small strainer out but was fairly clean. I cleaned it and replaced it but the noises and vibration remain. So will wait until I get rebuild kit. All that heat seems bad to me, after 10 minutes you can't put your hand on it.

[Glen]

Hi,
It is common for Touch Controls to make whining sounds.
I don't know how long you have had the Cub, or if the Touch Control is doing anything different than in the past.
If it is hot weather where you are, 90 degrees or more, the Touch Control is going to get hot eventually during use.

There may be nothing wrong with it, if it works normally.
But, I don't know without being there to see it.

[Jim Becker]

The important question is whether the pressure is unloading when it is idle. With nothing attached to the system, you should notice a relatively large load on it when it is moving down (back) that is not there when it is moving up. When it is idle, it should not sound like it is loaded, but should sound similar to the way it sounds when going up. If it acts loaded when idle, the pressure valve is not unloading. Maybe it is stuck. (The orifice/screen you cleaned earlier is part of what controls the pressure relief valve.)

[inairam]

I am usually whinny when I am hot.

I have a 74 that is hot. I can feel it through my boot if my foot is forward on the platform. I also have a 74 that I got late last year that I did not work on yet that the PO said it would stall if the TC was used and suspected something in the TC causing a problem. Was there something with 1974 TC units? I quote frankly have never had to go into a TC. They have just been reliable from my experience.

[bobburke]

It will heat up faster than the engine without moving the lever..when I bought it all the hytran was in the crankcase so it was quiet but didn't move. Rebuit pump to stop the leak and noticed the noise in the tc block. I think the filters are clogged and any small ports. Its bled correctly, filled to where it just comes up to the fill and fluid seems bubble free. Might have been empty and sitting to cause rust or dirt to clog it up. will see what rebuild and cleaning does. Thanks

[Shadow_storm56]

Mine runs at around 60c and stays there, I wonder if you are overloading it? I know mine makes a whine when it reaches max pressure and still wants to push further. Considering the small resivoir I would not be surprised if this made it get hot fast. I never had it ger as hot as some others here said so they must tolerate lots of heat

[bobburke]

So today I tore into my touch control block. Turns out one of the relief valve cylinders was put in backwards by a former owner. The offending part was about the size of a .22 shell and caused all the trouble. Now the tractor is quiet and runs so much better.
So the moral of the story is not to put everything back together as it came out but to follow the repair manual to the letter.