300U Loader and Bucket Leak Down

My original problem on this 300U is that the loader and bucket leak down and there doesn't seem to be a good fix The loader is currently plumbed though the original hydro touch valves but spending $1,200 or more on two new valves that are difficult if not impossible to find doesn't seem like the right thing to do right now.

What I am considering is to cut a section out of the pump pressure hard line then braze on two hydraulic fittings. This would allow me to feed a new style joystick or two spool valve for the loader with that pressure and then feed the return right back into the pressure line.

I actually can see a couple problems with doing this. (1) Would it work and still allow the rest of the system to function? or (2) Would it completely divert all pressure away from the power steering while the loader is in actual use? (3) If it diverts all pressure then how to combat that problem?

Obviously I would not want to cut an original hard line if this would not work anyway. However keeping the tractor "original" is not a big concern for me. I just need the loader to work properly.

Any help would be much appreciated.
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The first step is to be sure it is valving causing the leak down. Lift the the bucket a foot off the ground and put a jack stand under it. lower it onto the stand so
no pressure is on the cylinders. Remove and cap the hose going to the lift port on the valve at the valve. (not both of them) Gently and safely back off of the jack
stand. if it still lowers, it is the cylinder bypassing, not valves. IF it is the valve, you could put a power beyond cover on the outside of the valve, or remove one
valve and put the plate there. This would give you regulated access to hydraulic pressure. There is only pilot pressure in the line coming from the pump unless the
valves are moved. It is not a pure open center system. Jim

I should have mentioned that I have already confirmed the problem is in the valves. There is no leak down when isolated.

So you are saying that it would do no good to cut into the hard line. Where would I find a "power beyond" plate for this tractor?

With that said it is entirely possible that this one already has that "power beyond plate" in order to run the power steering but I'm not positive about that. If it does then could I tap that hard line? That line is about a foot long and goes from the outside forward valve to the back one that runs the fast hitch.

I am not sure how to post images here, but I have posted the same question on the redpowermagazine forum with images as well as some additional back story with this tractor.

No. The pressure regulator and safety/pilot valving is in the back valve IIRC. The system remains on near zero pressure until demand causes it to pressurize. The
Power beyond might be available on Ebay, or from Surplus Center.Jim
Source?

Since I cannot post any images here is a link to a picture that shows the PS system on my 300U. Even though it says IH330 mine is set up the same way with the exception that it uses the Tee that is shown in the lower left corner on the back valve also.

https://avspare.com/catalog/case/61642/54942/729064/

I believe - and correct me if I am wrong - that these end plates part #364878R1 are already part of the "Power Beyond" system and that I could use one additional Tee on the forward cap to tap pressure for a new loader valve. If that is possible would the return out of the new valve go to the reservoir?

Here is an additional link to my specific images as well as other information about my problem.

http://www.redpowermagazine.com/forums/topic/108616-300u-cutting-hard-line-to-get-hydraulic-pressure-for-loader/

The original "Touch Control" valves on your 300U never were positive-shutoff valves, and the 60+ years of
use and wear since they were new certainly hasn't improved their holding capacity. IH's solution used a
"cross-check valve" assembly, part # 363453R, which is a block which fits on the control valve, with the
hoses going to the cylinder attached to it. This keeps the cylinder from bleeding down in one direction
only, and the tractor has to be running to get the cylinder to move in that direction. These were typically
used on the Fast Hitch cylinder valve, and if your Fast Hitch doesn't bleed down you almost certainly have
one installed there. If you want to see a picture of one of these check valves, go to
http://www.messicks.com/cas/59117, click on Hydraulic system, then on the bottom link for the check valve.

The cleanest solution to your problem would be to get a couple of these check valve and route the hoses
going to your cylinders through them (note that the hoses can be hooked up backward). I'd try JP Tractor
and/or another salvage dealer. If worse comes to worst, I may have one or two of these check valves around
somewhere.

Good luck.

While a great idea - I looked this morning and the check valve would only fit the outer valve on the forward stack and only then if you could reverse the check valve so that the hose hookups were to the outside.

I can visualize that once two were mounted on the forward stack then maybe 1/4 inch clearance between each check valve and also the same clearance between the cast iron reservoir under the seat. One could never get enough room to hook up hoses on the inside valve.

Am I missing something here? Maybe a check valve with hose hookups out the bottom and not the side. Now I could make that work in a heartbeat.

The cross-check valves can be mounted either on the top or on the bottom of the OEM control valves. For
your side-by-side valves in the front gang you would put the check valve for the outboard control valve on
the bottom with a short 90-degree fitting on one or both of the inboard-facing ports of the check valve.
This is the usual way to plumb the Fast Hitch check valve so I'd take a look at yours assuming your tractor
is so equipped.

The check valve for the inboard control valve would go on top of the control valve; this may require
adjusting the position of the lever for the control valve. This yields four hoses going to your loader in a
confined area so giving some thought about the best way to route them is probably required.

Very good! and Yes, my fast hitch valve is plumbed with a check valve and hoses are facing to the inside which is why I did not think it would work. I never anticipated being able to put one on top.

I will go ahead and try to find a couple check valves and get them ordered in.

You have been very helpful and the info is much appreciated. It seems you have been there - done that.

When I get this project done - or run into trouble - which ever comes first - I will get back with the results.

Looks like I can get used ones for $50 each and new ones for $142. I'm sure excludes any shipping charges.

I can also see having to raise the seat about 1.5 inches to allow the hoses from the inboard top mounted check valve room to exit to the inside. I don't see this as a big problem.

Glad to hear you found the check valves are available. I don't think you need to worry about raising your
seat since the hoses from the top-mounted check valve should end up pointing outboard, not inboard.

So I purchased just one new check valve first just to get a feel for what I could be up against and here is that answer.

Check valve will not mount on top as the bolt hole pattern and port pattern does not match but they do when mounted on the bottom. At first glance you might think it would work as top and bottom are very similar but only two bolts will line up when top mounted and even if you could use only two and make it seal right then the port holes are off enough that there would be no flow between the loader valve and the check.

A top mount check valve must be manufactured different. I could not find any other part number for these things.

Second problem is that when the check valve is mounted on the bottom inboard valve the outlet ports from that check valve face inwards leaving no room to elbow down for the hose installation.

You cannot reverse the check valve so the outlets point outward due to the offset bolt and port pattern.

It was a great idea but "no worky" in my situation.