Leakdown

[woodlandfarms]

I was yacking with Pony a few minutes ago. Discussing sprayers. One thing that I reminded myself was that I have an issue with leakdown on the PT. The arm will lower, even when driving. It is not quick but not slow. In a space of 5 minutes or so it will drop a few inches. The reason this is a big concern is that if I front mount a sprayer I want it to stay at a particular height...

Any thoughts? I was planning on replacing the cylinders this winter if money is not too tight.

Carl

 

[SnowRidge]

This is clearly an opportunity for yet another mod. Three point hitches have position control, which keeps the lower arms from leaking down. I think your PT needs this too, but for the lift arms.

I think you should automate it. Use the joystick to set the arms and implement at the right height, then push a button and have something under software control take over and keep it at that same exact height. It wouldn't take much processing power. You could probably do it with a Pic microcontroller.

I'm really enthused about this. Please keep us apprised of how the project is coming.

 

[MossRoad]

Put wheels on the bottom of your sprayer in case it drops.

 

[woodlandfarms]

I think you should automate it. Use the joystick to set the arms and implement at the right height, then push a button and have something under software control take over and keep it at that same exact height. It wouldn't take much processing power. You could probably do it with a Pic microcontroller.

I'm really enthused about this. Please keep us apprised of how the project is coming.

It is moments like these that make me realize how wonderful TBN is... in a private email Snowridge has invited me to his neck of the woods, and on his nickle no less. As he is an expert in electronics and the PT he has offered to build the system for me while I am there, and test it on his system, and then fly me back so I can install it on mine... With friends like this I can't wait to discuss my Stump Grinder idea.


ps... all in fun... Actually not a bad idea if it wasn't for the fact I have no mechanical or electronic skill whatsoever. And now with the writers strike my pocket book is on permanenet tractor hiatus. Also, I would have thrown in Lasers to keep it all level and then keep me on track for multiple passes...

 

[Gravy]

Going to the other extreme, for an application like a sprayer you could use Hillbilly High Tech - a sturdy stick wedged between the body and the lift arms to support it all for a while.

Gravy

 

[marrt]

woodlandfarms,

Have you tried fiddling with the draft control? I was playing with mine over the weekend and found I could make the bucket move (up) be changing the draft control and increasing the rpms. It could be hard to fine tune though. I also wish the arms would stay in one place. I have a garage to build and would like to use the PT bucket for a platform and to stabilize ladders and such. With the arm leak down issue, this is difficult.

 

[MossRoad]

... Also, I would have thrown in Lasers to keep it all level and then keep me on track for multiple passes...

Don't laugh. It has already been done. I think it was Blackwell that mentioned they have a laser controlled depth thingy on one of his PT's for when they level areas.

 

[MossRoad]

Yep, it was Balckwell. Here's a link to the post where he mentions it.

And here's another mention of it where he mentions a power rake and laser level.

 

[SnowRidge]

It is moments like these that make me realize how wonderful TBN is... in a private email Snowridge has invited me to his neck of the woods, and on his nickle no less. As he is an expert in electronics and the PT he has offered to build the system for me while I am there, and test it on his system, and then fly me back so I can install it on mine... With friends like this I can't wait to discuss my Stump Grinder idea.

--ROFL--

 

[J_J]

I was yacking with Pony a few minutes ago. Discussing sprayers. One thing that I reminded myself was that I have an issue with leakdown on the PT. The arm will lower, even when driving. It is not quick but not slow. In a space of 5 minutes or so it will drop a few inches. The reason this is a big concern is that if I front mount a sprayer I want it to stay at a particular height...

Any thoughts? I was planning on replacing the cylinders this winter if money is not too tight.

Carl

Carl, That leak down is probably caused by your joystick valve. Some valves are made to tight specification, and others are not. I took my valve out and had it checked by a hydraulic shop. There are pilot operated check valves that you could add to the cylinders, that are activated by you moving the valves. What that does is to allow say a pressure of 600 psi to open the valve so fluid can flow to the cylinder. The purpose of the pilot operated check valve is to hold a cylinder in place. That is assuming that the cylinders are good. A lot of valves have internal checks in the valves, but that is to prevent a load from dumping when you shift the valve. You might consider a newer model valve. I think all of us have a leak down on the lift arms. My lift arms will drop over night. Some say they can watch them drop in a matter of hours. Hope this info helps. Good luck.

 

[RegL]

Kind of low tech, but how about a couple of pieces of channel iron,cut to the right length, that will slip over the rods of the lift cylinders so they can't close all the way. I'm not to sure what kind of weird stresses that would put on the lift cylinders though.

 

[Rip]

Carl,

I agree with J J in that most of the leakdown is probably in the joystick spool valve. A new one may reduce the problem, but to an extent it is the nature of the beast. Fancier equipment uses pilot valves and there are pilot operated check valves that can be placed between the spool valve and cylinders.

This is another example of the pros and cons of PT using 70's technology.... low cost and simple componants versus more sophisticated, but more prone to contamination and costly failure.

If the only real problem this leakdown causes is spraying, then go one step beyond Gravy's suggestion and make two channel-type support props like most machinery today comes with for when doing maintanence under raised lift arms. design them with lips or other feature so that they can not vibrate loose while moving. As RegL just posted above !!

 

[woodlandfarms]

woodlandfarms,

Have you tried fiddling with the draft control? I was playing with mine over the weekend and found I could make the bucket move (up) be changing the draft control and increasing the rpms. It could be hard to fine tune though. I also wish the arms would stay in one place. I have a garage to build and would like to use the PT bucket for a platform and to stabilize ladders and such. With the arm leak down issue, this is difficult.

When I installed my new fangled mower blades I had to crank the draft control all th way up... That little bit of weight made the draft work twice as hard...

Carl

 

[SpringHollow]

Hi Carl,

I recently discussed this with Terry since I think it is unsafe. I said I had heard there are 2 types of valves, one leaks and one does not and asked which they used. He said theirs leaks, depending on load about 1/4" drop per minute.

As part of the boom mower setup, they install hand valves on your lift cylinders. You raise the counter weight to about 18" off of the ground and then close the valve and the cylinders stay where they should. I tried where I wanted to unload a bunch of items off the forks at an elevated height. It worked but then the curl dropped slowly. I would need to add another set of valves for that. The better solution is to correct the problem with pilot valves or a better valve to begin with. This is high on my wish list.

Just recently, I started having a problem with the joystick valve not working properly. Sometimes when I try curling, it dumps instead. I assume I have a piece of crud in the valve. That will teach me not to run my filter cart for a couple of months!

Ken

 

[marrt]

If anyone finds a suitable alternative valve, please post a link here. Although it's safer with kids (bucket will always leak down), I don't like the leak down feature. I would fix it if I found an alternative.

 

[SnowRidge]

If anyone finds a suitable alternative valve, please post a link here. Although it's safer with kids (bucket will always leak down), I don't like the leak down feature. I would fix it if I found an alternative.

Why would it be safer? I'm not disagreeing, BTW. I just don't understand.

 

[marrt]

Why would it be safer? I'm not disagreeing, BTW. I just don't understand.

The logic I've heard: If you forget to lower the bucket for example, it will leak down in a few hours. So there less danger that a kid will accidentally, or purposely, lower the bucket on your cat.

 

[SnowRidge]

Now I get it, and I would be more worried about the cat lowering it on me.

 

[J_J]

The logic I've heard: If you forget to lower the bucket for example, it will leak down in a few hours. So there less danger that a kid will accidentally, or purposely, lower the bucket on your cat.

This a pilot operated check valve. They are not cheap., at around $99. It will release at 60 psi. You could install high pressure shut off valves. They are around $15 to $30 bucks.

 

[MossRoad]

Now I get it, and I would be more worried about the cat lowering it on me.

You know, all joking aside, I'll bet you could find some stories similar to that situation... I've heard a few about hunters being shot by their dogs, so it could very well happen.