354LE TPH PULSATING

[pej2945]

My 354LE TPH is pulsating, it drops about one inch and than raises back up about every 7 to 10 seconds. I have the new style 354 that has no draft control lever and the knob in front and under the seat controls the speed of the lift. Also there is no top plate on top of the TPH box. When I shut of the tractor the TPH drops with in 5 minutes. If I change the pistons o-ring can this be done by just removing the plate with the TPH speed control knob and pulling out the piston? I’ve looked at some of the past post but don’t see a clear answer to this problem.

 

[bluechip]

It sounds like the o ring on your lift piston is bad, This is in the cylinder inside the lift box.

 

[pej2945]

Any idea on how to change the o-rings?

 

[ZionHill]

Here's a great pictorial on how to do it:

http://www.tractor-outlet.com/toservice2.html

Even if you have a different model than pictured the info is still pertinent

 

[bluechip]

The photos, article posted are for a 200 series (18-28HP) and the 354LE is different. It may require removing the lift box and unbolting the cylinder from the bottom to remove it or their may be access. the "single lever" box is new and I have not seen it, someone did post some pictures of one a while back, it was a gasket repair on a tractor loosing hyd. oil into trans...

 

[ghidley]

Any idea on how to change the o-rings?

You can access the o-rings by removing the inner cylindar and piston through the front after removing the lift control valve under the seat. You need to take the shift levers off to have clearance to do this.

To reinsert the cylindar while retaining alignment of the inner rod, you can use a paper towl cardboard tube inserted through the cylindar while inserting. Then you can insert the piston.

greg

 

[Affordable]

On the new style hydraulic lift boxs,we remove the hydraulic lift box,remove the cylinder,replace the o-rings and stop ring.We have rebuild kits for the 3-point,however there are 2-sizes of pistons.No rime or reason or no way to tell until you remove it which one you have.

Tommy
Affordable Tractor Sales
Bellville,Texas
979-865-4002

 

[Ranch_Hand_Supp]

My 354LE TPH is pulsating, it drops about one inch and than raises back up about every 7 to 10 seconds. I have the new style 354 that has no draft control lever and the knob in front and under the seat controls the speed of the lift. Also there is no top plate on top of the TPH box. When I shut of the tractor the TPH drops with in 5 minutes. If I change the pistons o-ring can this be done by just removing the plate with the TPH speed control knob and pulling out the piston? I’ve looked at some of the past post but don’t see a clear answer to this problem.

I have had a few people send/ship me there single lever lift control valve for me to go threw and I found the problem to be in the lift control valve.

Trying to control draft and position at the same time.

Not saying for sure that is your problem but makes me think so.

Ronald
Ranch Hand Supply

 

[Soundguy]

What method of control and exaust valving does that system use? Anything like an unloading type valve setup?

Could also be another inernal leak..like a safety valve..

Soundguy