3 pt does not lift at idle?

[snowman64]

I recently put a 800 lb tiller on the back of my newly acquired 2002 TC45 and it will not lift it at idle, if I raise rpm up to 1400 it will lift it slowly. i have searched the forums and believe this could be caused by sticky pressure relief. also is there a shim kit available? and do you add or remove shims to get it raise pressure if it is low? The tractor has 250 hrs and plan on changing the hydraulic oil soon. fluid level is good. but was just curious if anyone else has experienced this?

Thanks in advance
Steve

 

[Hooked_on_HP]

My first guess would be the seal on the lift piston. Lift the tiller all the way up and the close you flow rate valve all the way. If the TPH drifts down it is the seal on the lift piston.
Bill

 

[snowman64]

Will try that tomorrow and let you know. Thanks-Hooked on HP

Steve

 

[N1ST]

I have a Kubota, and this is normal behavior for it.

 

[radman1]

A TC45 should be able to lift an 800 lb tiller easily at idle. My prior Case-IH DX29 (TC29 equivalent) would easily lift that. TC45 should be able to lift 2300-2400 lbs 24" behind the lift. Something is wrong with your 3 pt.

 

[jinman]

Steve, do you have a FEL? Hydraulic remotes? Is the 3PH the only thing being operated by the hydraulics?

If you have a FEL or remote hydraulics, you can test your pressure there with a gage in the quick connects. DO NOT try to adjust your hydraulic pressure without being able to measure it. You can buy a shim kit from your NH dealer. The shims go in the pressure relief valve that is located in the hydraulic diverter valve under the right side of the operator's platform. This affects maximum pressure only. It does not affect flow rate. The amount of pressure determines how heavy a load you can lift. The amount of flow determines how fast you can lift it.

I think you need to shut the engine off with the tiller lifted all the way up and see if it drops. It sure sounds like your lift cylinder or HPL valve might have a leak.

 

[snowman64]

Steve, do you have a FEL? Hydraulic remotes? Is the 3PH the only thing being operated by the hydraulics?

If you have a FEL or remote hydraulics, you can test your pressure there with a gage in the quick connects. DO NOT try to adjust your hydraulic pressure without being able to measure it. You can buy a shim kit from your NH dealer. The shims go in the pressure relief valve that is located in the hydraulic diverter valve under the right side of the operator's platform. This affects maximum pressure only. It does not affect flow rate. The amount of pressure determines how heavy a load you can lift. The amount of flow determines how fast you can lift it.

I think you need to shut the engine off with the tiller lifted all the way up and see if it drops. It sure sounds like your lift cylinder or HPL valve might have a leak.

Jinman

It has a fel, i lifted the tiller and let it sit for a 1/2 hr, and it appeared to drop 1/8 of an inch in that time, will look for a pressure gauge setup on Monday and let you know. can you tell me if the adjustment on the 3 pt arm that comes out of the 3pt shaft would effect this? due to the fact that the other day I noticed that the jam nuts where loose, so I reset the position to where the paint marks where on the threads. It was acting the same way prior to adjustment.

Steve

Steve

 

[Soundguy]

I'd pressure test the system.. if you have remotes.. use them.

as for the relief.. hold off on adjusting it till you do a lil more troubleshooting.. but in general, a relief isn't much more than a ball and seat and a spring under tension.. thus usually adding shims adds more spring pressure, thus more relief pressure. I HAVE seen different setups.. and I'm not familiar with yours.. but in general.. that's the basic principal that they work under. some use a more conventional valve and seat vs a ball and seat.. but same idea..

a tc 45 should be able to snatch 800# up... I have antiques that will lift round hay bales on stock old hyd systems... and I know that 45 is a much better machine..e tc.

soundguy

 

[RickB]

It could easily be caused by a plugged hydraulic filter. I'd start with a fluid and filter change first, as you are going to do that anyway. Remember the hydro charge filter too, if it is a 'D' model. I'd do the oil and filter change before even buying a pressure gauge.

 

[jinman]

Jinman

It has a fel, i lifted the tiller and let it sit for a 1/2 hr, and it appeared to drop 1/8 of an inch in that time, will look for a pressure gauge setup on Monday and let you know. can you tell me if the adjustment on the 3 pt arm that comes out of the 3pt shaft would effect this? due to the fact that the other day I noticed that the jam nuts where loose, so I reset the position to where the paint marks where on the threads. It was acting the same way prior to adjustment.

Steve

Steve, since you have a FEL, does it act normal? Does it raise and lower as you'd expect it? Your FEL and 3PH use the same hydraulic pump and system. If the relief valve is stuck open, your FEL will be very sluggish too. One thing you might try is to jiggle your FELs joystick while raising the 3PH to see what effect it has. The FEL operating should disable the 3PH because of the open center system and the action of the priority valve.

RickB has a good idea about changing fluid and filters, especially since you are so close to that interval anyhow. Your hours are not up there, but if your tractor is a 2002, it's time to do a hydraulic service anyhow. With so low hours in 7 seven years, it's been sitting idle a lot.

The adjustment screw you mentioned sets the maximum 3PH height. If it is adjusted too short, when the 3PH raises all the way to the top, the hydraulics will keep trying to raise the 3PH and the relief valve will open. If it is adjusted too long, the 3PH will not raise as high as it should before stopping. Normally, that arm is adjusted with the lift arms all the way up. Start with the adjustment too long and then adjust to shorten the rod. When you hear the engine load up and the relief valve lift, adjust the other way (longer) one full turn and you hear everything go back to normal. That's the correct position. Run the 3PH up and down a couple of times to make sure it does not make the relief valve go to bypass at the top. Lock everything down and you're done.