3-Point Hitch 3-point Hydraulic cylinder has flow by

[clemsonfor]

Thanks for the two pics. Can you tell me why removal of the housing is necessary to make the repair ?

You have to remove the whole assembly so that you can rotate the rockshaft out of the cylinder bore and pull it out allowing you to take a a wood dowel or something and push the piston out that will be stuck in with friction from the oring in the cylinder. The rock shaft and piston ARE NOT connected!

Pulling the end cap off you have to pull something toward you that is inside a pipe of very similar diameter with a huge fat oring around the edges that creates friction.

 

[clemsonfor]

Here is my post.

http://www.tractorbynet.com/forums/yanmar/254837-clemsonfors-hydraulics-rebuild.html?highlight=

 

[Ben755]

Thanks to everyone for their input and comments on past experiences with this repair job. The posted pics are of great benefit also. I won't be going into this job blind now, and I'll know what to expect and can prepare somewhat for what I'll need to do when I start the job. I have about another week of pasture shredding to finish before I can get started on the repair work. The 3-point can still hold the shredder up, but as heat and pressure build, the lift arms start to fall slightly (about 1/4") and then jump back to correct itself . This occurs periodically, initially at about every 4 seconds, and later, every second, causing a slight jolting motion on the tractor.

 

[clemsonfor]

could be something in the valve worn too. Have you locked out the 3pt to isolate the cylinder to see if its the culprit and not the valve leaking?

The shaft on the valve can just wear in the bore and cause a leak. I replaced the orings in my valve as well but it still have a minor leakdown but I live with it. I rather it not but for the small amout it does and the cost of a new valve I will live with it.

 

[normde2001]

Sounds as if you need something like this. Have been using these check chains to determine the height of my cutter and keep strain off 3ph for about 15 years. Unfortunately don't remember where I got them or exact name.

 

[clemsonfor]

View attachment 485543Sounds as if you need something like this. Have been using these check chains to determine the height of my cutter and keep strain off 3ph for about 15 years. Unfortunately don't remember where I got them or exact name.

where do those attach too? looks like they go from the lower pin to the upper arms? how does that keep the pressure off the 3pt if they go to those?

 

[Gunny]

Check chains are run from the lower pin on the implement to the upper pin on the top link. Once adjusted, the implement is held by the chains, not the hydraulics. Another good thing with them is that if you have to lift the implement, then all you have to do is just drop the lift and it will go back down the limit of the chains, no need to adjust height up and down again.

Some people call them limiter chains.]

Here is a PDF on how to make your own

http://www.ntractorclub.com/howtos/pdfs/Limiter-Chains.pdf

Here is a set for sale

Chain Limiter Kit

 

[Ben755]

could be something in the valve worn too. Have you locked out the 3pt to isolate the cylinder to see if its the culprit and not the valve leaking?

The shaft on the valve can just wear in the bore and cause a leak. I replaced the orings in my valve as well but it still have a minor leakdown but I live with it. I rather it not but for the small amout it does and the cost of a new valve I will live with it.

The closed lockout valve under the seat will not hold the lift arms with load when the engine is shut off. I also notice some hydraulic fluid tends to leak under one of the end caps where the lift arm attaches to the shaft.

 

[Ben755]

Check chains ? Interesting idea - I may give it a try if I can put it together.

 

[normde2001]

Right, gunny, top link bracket. Chain Limiter Kit That would be the one.

 

[clemsonfor]

The closed lockout valve under the seat will not hold the lift arms with load when the engine is shut off. I also notice some hydraulic fluid tends to leak under one of the end caps where the lift arm attaches to the shaft.

Mine did this as well until recent ( I think I fixed it). There is just an O ring under those lift arms, and that fluid is not under pressure there it just splashes up and is just in that compartment (as described by HOye and which I knew there was no pressure on those) . Its more to seal out water entry than anything. But its just like a $0.75 O ring that is behind that cover plate on the outside. When you buy parts get 2 of those and take that bolt of the end of the arm and pull the arm off to get the old oring out or dig it out with a pick and put it all back on there including the washer on the shaft and put your oring in there and put the cap and bolt back on. Once you know what your doing it can be done in less than 10 mins a side.


And from your description yes your cylinder O ring is shot.

 

[clemsonfor]

Check chains are run from the lower pin on the implement to the upper pin on the top link. Once adjusted, the implement is held by the chains, not the hydraulics. Another good thing with them is that if you have to lift the implement, then all you have to do is just drop the lift and it will go back down the limit of the chains, no need to adjust height up and down again.

Some people call them limiter chains.]

Here is a PDF on how to make your own

http://www.ntractorclub.com/howtos/pdfs/Limiter-Chains.pdf

Here is a set for sale

Chain Limiter Kit

This still makes no sense to me? How can this hold the implement up? the top link is lifted with the arms as a unit attached to the implement, so attaching chains to the lift pins to the top link, doesn't that still mean the 3pt is supporting the weight? Im just trying to understand this hear and wrap my brain around it.

 

[clemsonfor]

This still makes no sense to me? How can this hold the implement up? the top link is lifted with the arms as a unit attached to the implement, so attaching chains to the lift pins to the top link, doesn't that still mean the 3pt is supporting the weight? Im just trying to understand this hear and wrap my brain around it.

Ok I opened the link on how to make them and see that its attached to the tractor top link mount not the upper or outside end of the Top link on the implement side.

 

[Ben755]

Don't know that this will help. Picture of an FX24D. Second picture showing where the housing bolts down.

Were you able to replace the gasket between the housing and transmission or reuse the old one ?

 

[clemsonfor]

Were you able to replace the gasket between the housing and transmission or reuse the old one ?

I doubt it! If the one he was working on was like mine (mine Is a VN recon and they use some paper gasket and crazy strong glue. I have to take a wire wheel to clean it off. THey put it on every gasket!!!

I would not reuse a gasket unless its rubber and in good shape for this, you don't want a leak and have to redo it. That said I used silicone (ultra grey) to seal mine up. Just clean your surfaces up well and use like brake clean or some solvent to clean oils off the mating surfaces and put a thin layer on both surfaces and really you snug the bolts hand tight let it sit for an hour then torque them down then wait 24 hours before you use it or put oil in it. Most people skip this process and I use to and usually it doesn't matter but you can see why it works better this way. For this application you can fill with oil basically right after since it sits above the oil line but if you want to stick to the 24 hour rule just done run it till the next day.

I use silicone on pretty much any one of the gaskets I take off my tractor. If you careful and esp if you wife the gasket mating area you don't get the amateur silicone splooge everywhere the surfaces meet like most idiots leave.

 

[winston1]

Pretty sure I replaced it but it has been awhile. If it doesn't tear up it would be fiie to reuse, maybe a little sealant on it. You can buy sheet gasket material at any auto parts store and cut one out using a ball peen hammer. Ever done that? Gasket Material for Cars, Trucks & SUVs

 

[clemsonfor]

Pretty sure I replaced it but it has been awhile. If it doesn't tear up it would be fiie to reuse, maybe a little sealant on it. You can buy sheet gasket material at any auto parts store and cut one out using a ball peen hammer. Ever done that? Gasket Material for Cars, Trucks & SUVs

that's an awful lot of work when a silicone will work.

If your buying stuff from hoye and can get one for a few dollars I might do it, but I would use silicone way before I bought sheet gasket and beat one out of it. MOst folks have no idea what or how to do this now a days.

 

[Neat 1500]

I have a roll of gasket paper here but it's not my favourite past time cutting gaskets out of it, only if really required :confused2:

 

[Ben755]

After replacing the piston seal ring on the hydraulic lift, the lift arms raise. but don't lower. The position of the end cap on the left lift arm controls some type of valve (pic below). Is this a pressure relief control ? Could the position setting of this control be the problem ?

 

[winston1]

I don't think it controls a relief valve but really don't know what it does. Any reason to believe it is in a different position now then before? If not, doesn't seem reasonable that would be your problem. Do you have weight on your 3 point? Is the stop valve open?