336E Hydraulic Boom Down and Bucket problem

[Epicmehcnaix]

I have a 336E with a Prefix of FJH That i am currently working on. When i use the boom down function it will not lift machine but if i apply a small amount of movement on the stick lever (just enough for it to register that i am using the stick) the boom will easily lift machine. the bucket is the same way. it will curl in very slow but if i use the stick while curling it will curl at normal speed/strength. changing the pattern lever does not change the problem. any help would be greatly appreciated

 

[Epicmehcnaix]

not sure if I posted this in the correct spots? Never got any reply’s.

 

[Chrisso]

Thought this question might've generated more discussion too. I'm working on it, but there's more experienced folks here that already have the knowledge.

At first glance I'd say this was a resolver issue. But after reading up it could be something else causing a pump stroking issue. There are 2 main pumps on your machine, a drive pump and an idler pump. Both are equal in output. The bucket hydraulic circuit is supplied by the drive pump only. Stick is controlled by both depending on joystick position.

Are any other functions operating slow on this machine? Did this issue happen all of a sudden overnight or has it developed gradually? How many hours on the machine?

Also without the full s/n we can't tell if it's one of those hydraulically regenerative 336E's either. They have a bunch of additional hydraulics to complicate things. Does it have the two big accumulators recessed into the inside of the counterweight?

 

[Ollie]

The hydride 336 e/f have accumulators in counterweight