David brown loader

[Bald n Grumpy]

Have a GD90 loader on a 1390
Loader has an intermittent fault and won't stay up
Sometimes it will hold with a bucket full and other times it won't hold without attachment on and drop's quite quickly
First thought is seals but don't think it is . Double acting rams and original valve block which has up , down and a float position which I've not come across before
Any thoughts
TIA

 

[Boohoo]

My LQ9 is doing the same. It can only be the seals in either the rams or the valve block. It's just a case of replacing seals until the problem disappears. I'd start with ram seals unless the valve block looks like the Torrey Canyon

 

[Daddy Pig]

Can you swap the hoses so the crowd and tip valve does the main loader boom, if it still drops this would point to ram seals, if it doesn't it points to valve block

 

[Boohoo]

Can you swap the hoses so the crowd and tip valve does the main loader boom, if it still drops this would point to ram seals, if it doesn't it points to valve block

Good idea! Can't do it on my LQ9 but the GD90 is piped differently so it is possible to swap without adding extra hoses.

 

[Mur Huwcun]

Easy way would be to fit a lever tap on the lift pipe where you disconnect the loader, lift up and close tap. If it still goes down, oil is passing the ram seals. Another way is lift it up and disconnect the power down pipe, if oil seeps through, again it’s ram seals. You just need to be confident which pipe does what.