Yanmar YM336D Slow Loader - Pressure Relief or Bad Cylinders or ?

[J_J]

Have you removed the spool from the valve? It would be hard to jam up all the lands on the spool

Have you tried removing the hose to the cyl and place in a bucket and checking flow using the lever.

The flow should be same from both hoses. Can the valve put one gal of fluid from each work port in the bucket in 6 sec?

If the spool is clear and moving the same, and the hoses are the same and the fittings are the same, there is no reason that you should not have equal flow.

If not, then the spool is jammed up with debris.

Swap the hoses and see what happens.

You do have the work port hoses connected correctly.

The hoses from a cyl should go to the same set of work ports on same spool.

 

[rScotty]

Swap the hoses and see what happens.

The hoses from a cyl should go to the same set of work ports on same spool.

Swap the hoses....?
I like that idea!
rScotty

 

[jsdepottey]

rScotty and J_J
I got a chance to switch the hoses tonight. I re-installed the QD's on the hoses to make it easier to swap them around. Using the bucket spool on the valve let oil go back to the sump raising and lowering the boom. The pressure relief no longer goes off on the way up or the way down now. Pressure around 500 psi on the way up, still takes about 19 seconds to full up position. It lowers very quickly with no pressure on the way down in about 5-6 seconds. No difference in speed raising the boom using the curl bucket port to raise boom vs extend bucket bucket to raise boom. Still takes along time to raise I think but maybe I was spoiled with my old skidsteer speed. Is that what I should expect?

 

[J_J]

Well, you can go to Surplus technical help section and insert some figures and see the results.

Go to calculators, and the force and speed.

Then at the bottom insert the GPM and it will show the time.