Hydraulic Surge only stops when....

Hi guys, having problems with my Tele-Depth 2 point hitch system on my Farmall IH 460 Diesel. I'm getting a hydraulic surge that has a steady rhythm to it. It is the hydraulic pump that I replaced last fall and I don't want to damage it. It quits if I move the lever up or down as long as the lift is moving. Then when the lift has found its position the noise starts again. The only other thing that makes it quit is to move the control lever SLIGHTLY in the down direction. Then the noise stops for a while. If/when the noise returns, I can make it stop by moving the control lever in the downward direction SLIGHTLY again, like I'm following the problem down. If I put the lift all the way down, with the lever in the full down position, the noise is there.
I'm lost. I just today removed the check valve and the saftey valve and inspected them and didn't notice anything wrong with anything.
I need some direction, PLEASE.
Tod.

Unfortunately, you're venturing into areas where few living people have experience. Lots of people can tell you how to deal with engine problems because engines are basically the same the world around.

Dealing with the idiosyncrasies of a 460's hydraulic system, which is unique to the '60 series of tractors, is another thing altogether. By comparison, TA's and transmissions are simple. You can take them out, hold them in your hand, SEE how they work. Plus they're essentially the same over several generations of tractors. Not so with that hydraulic system.

I'm sorry I don't have any suggestions as to your problem. I was just hoping to shed some light on why you're not getting the help you need.

Once a few years ago I came across an online article written by a person who had hydraulic problems with his 560. IIRC, he ended up taking most of the system apart piece by piece until he found his problem, and learned a bunch in the process. Wish I could find it again, or remember who it was that wrote the article. I had it bookmarked on an old computer that's long gone...

I think this is the article you are talking about. I've read it a
few times myself and you're right, It is very helpful. Problem
is it doesn't apply to my problem. Thanks for the reply
anyway.
Here's a link,
Tod.
http://www.oldoakfarmalls.com/
Hydraulics%2060%20Series.htm

Does anybody think this surging would stop if I drilled out
the orifice hole a little? I did some reading on this link and
noticed that someone had recommended a Guy to drill it out
with a 1/64 bit and it should correct the problem.
Is this to big? If so, how big should I drill it? Will it fix the
issue?
Thanks,
Tod.

Me again. I should like to add a little to my explanation. I didn't go into the teledepth valve very far. When these tractors were brand spanking new, we had a lot of trouble with whining, sizzling hydraulics and burping along with poor accuracy of the hitch. In other words when you moved hitch up a little it went too far or down too far. That part was basically corrected with the new rod style linkage over the original cable linkage. Converted a lot of them. Far as the burping, well, here is what IH did and it helped a great deal. Inside the teledepth valve, they cut a groove in a crescent moon shape. It matchs the regulating land on the spool and makes for a smoother cutoff of the flow to the orfice in regulator. This can be seen by taking the top off the valve and looking . You will have to look under the diff gears and move the valve spool forward by moving lever. If it does not have that groove machined in there I doubt if you will ever get it to work well. The part number was advanced on suffix or changed, don't remember that. Now, far as drilling orfice, like I said before, original was .031 with check ball and hardened seat. Replacement was .031 without check ball and no hardened seat. The 300 and 400 tractors had a .024 orfice but replacement is also .031. I have drilled many. Usually to overcome system going on high pressure when it warms up and then of course it gets very hot. You are expermenting when you start drilling. I have a set of wire gauge drill bits that run from number 80 to number 40. They move in small increments. So, if you start drilling that orfice you start by going only about .005 larger at a time. I figured this out by studying the operation of the system in the book and decided that is the valves wear more fluid will pass the control land than what can go through that orfice, therefore I started drilling them out. Later, I found that a lot of mechanics were doing that also. I also hooked them to a flow rater if possible when I did this and warmed them up really good to make sure everything still worked properly. Too big a orfice and system will not operate on demand it will just stay in low pressure stand by mode. Good luck.

I would be very careful about drilling out orfices or adding "metering notches" (what pete is talking about with the crescent moon shaped cut) to valve spools. Generally there is a lot of engineering that goes into those things, but as pete said, maybe as other parts and pieces wear, driling out an orfice may compensate for wear elsewhere in the system.
One question here though... why are we jumping from thread to thread on the same problem??? Woudn't it be easier to keep it all together?

Oh, I'm not talking about adding a crescent groove. I am saying to check to see if it has it . You would have to get a different later valve if it doesn't have one. , Even to copy if you had the proper expertise to machine it . Far as drilling the orfice, it is a often replaced seperate part so if you get it wrong you just put in a different one, no big deal.

Hi IH fan, I want to explain why I change threads rather than
staying in the same one. In other threads I had asked a
specific question and when it was answered I ended the
thread. I'm not real savvy on forums so if I should stay in
one thread I certainly can. My thought was, for example,
when I asked for a flow description of my hydraulic system
and it was answered, I thought it would be senseless to ask a
further detailed question in the same thread. I didn't think
anyone would see my new topic question. That's the only
reason I posted a new thread.
If this is not standard operating procedure, please let me
know what I should do.
To be honest, I want to drive to your house and or Pete23
house and sit down over some coffee so I can ask question
after question and gain some of the knowledge you guys
have. Which way would get more response for the issue I'm
having?
Tod.

Pete23, van you email me so I can ask you some specific questions? If contacting you on here is the best way to talk to you I can still do that but I really sense that you really know about the problem I'm having and know what your doing. Not that the other responses don't know, I just have gotten more responses from you and seem to Connection with what you are saying.
I ha!ve included my email in this response, I think that Should make it possible for You to send me an email. If not, I'll post it in another reply.
Thanks for all your help, I wish I had your knowledge.
Tod.

Tod, you're okay doing things the way you are. What I've noticed is that if you ask a follow-up question in a thread, it often gets ignored.

Keeping specific topics separate helps keep them from getting lost in the noise of other topics.

That's what I experienced mkirsch. If the original post
question was answered, the follow up questions were lost.
If/when I post the follow up question in a new post, I got an
answer right away. But I can see why the question was
asked to. I certainly don't want to mess things up either. I
really appreciate everyone's help in this forum and don't
want to offend anyone or make it confusing.
Tod.

Hi Pete23, I lost our emails and can't find your email address. Can you email me again? I want to go over the list of things you thought I should check before I drill out my orifice.
I really appreciate your help,
Tod