tipper hydrulics

[GERRY]

i am having a bit of aproblem with the hyd... on my s/dexta, when ihavethe lever in draft ,lever pointing
down , she will lift the tipper as usual and drop it no problems , when iput it in position control ,, she
will lift ok but will not stop untill the tipper is fully raised ie ican not control it , and it will not drop untill i push the draft leaver downwards, it wont drop in position , this is only with the trailer when ihave the link box
or other implement on position works fine. what could be causing this Gerry

[Brian]

There is nothing wrong with the tractor it is the operator that is at fault!

In the handbook and on this site it says very clearly NEVER use Position Control when using the Auxiliary Service Port.

I have written it many times on here. When in Position Control the lift arms control the control valve via the lift arm cam and linkage. If the lift arms drop, the cam will move the control valve to raise them. The oil to raise them is being diverted to the implement on the Auxiliary Service Port so that will go up uncontrolled. Even if you put the control lever fully to lower it will not stop.

Many loads of grain have been tipped between combine and grain store for the same reason. Many loaders have lifted through the roofs of sheds too. I have been called out many times to sort out reported lift problems only to find people were using the wrong service.

Never use Draft Control to hitch onto an implement either. If the implement moves and pushes on the top link, it will also cause an uncontrollable raise and this can cause major damage.

Heavy loads on the linkage that pull back on the top link will also cause problems. I once had a customer complain that his 100 gallon crop sprayer kept dropping but the tractor would hold a plough. Turned out the sprayer was being used in Draft Control not Position Control and the sprayer pulling on the top link was causing it to drop.

[GERRY]

well and truly told off , but a plesure to know at least the tractor is good
i can live that , thanks again Brain for you prompt rely , Gerry

[Brian]

Trying to save your life or limbs Gerry! Do not want to loose you.

[agroman]

Well reading this old post, I have just learned something which I really should have known! All these years I have been using the loader, which is tapped off the ASV with the lever always in position control not draft. In fact don't think I have ever moved my draft control except when adjusting the linkage a few years ago during restoration.

Even done the shed roof trick - but don't tell anyone - they all think it was the wind



Will have to try loader with draft control lever dropped.