Hi all. My old machine has been running very reliably lately, that I haven’t had to bother anyone on here…. It’s having trouble using boom and dipper together to try and finish pads smoothly. It could be operator, but as soon as you stop bringing the stick in, the boom takes off like lightning. Reading older post on here, could be o rings damaged in valve bank (although it has no leaks from control valve block), passing piston in boom cylinder (I have resealed both dipper and crowd in the last year), or adjustment of wobble sticks (I used a post from way back where @alrman gave instructions on how to switch sticks to excavator controls by making up new connecting rods down to control bank). Maybe they need adjusting? Maybe a bad relief valve in the boom control block? Heck maybe it’s the main pump that can’t keep the oil up to multiple functions! Is there a best place to start looking?
Practice, practice, practice..... You need to feather the controls, probably nothing actually wrong with the machine.
I put it down to my own inability too mate. But yesterday I worked it for a few hours and blew a hose on the front bucket which I didn’t see until the hoe stopped operating. Replaced hose and oil and ever since the boom raise has been sluggish. I changed the hyd filter and it got slightly better. I parked it up until this morning and gave it a run and everything is working fine. I checked the relief valve for boom raise and it looked ok, but I can’t move the poppet inside it, and I’m pretty sure it’s meant to have an adjustment stud in the back of it like the rest of them on the bank? (Pictured). I was thinking maybe the pump maybe on its way out but the front circuit works fine. Is the cold oil making a difference maybe? System was very hot yesterday when working. Tempted to pull the boom ram apart and double check the seals in there.
Could be lot of air running til low give it a hour with all functions cycled. Without digging or touching ground reach out work 3 functions together bucket, dipper & boom keeping teeth level as it comes to you. Before taking all apart
Does seem like there could be an "air lock" issue that was affecting it, especially how it seemed to be okay the morning after. You're right, there should be an adjustment screw on the end of that valve. They need to be checked with a hand pump to see the pressure they are relieving at. ... I do know where you can get another one of those relief cartridges if you need one .... the upper & lower valves are different on the boom section - different pressures
It has gotten better but still doesn’t seem like I was. Unless I’m playing it down now. It really calls for full revs to operate more than one function simultaneously. It never needed full revs to do anything. @alrman I just jumped in your website and saw you have a variety of used valve components for sale. I will try and contact you this week to see what I’ll need. The face mine doesn’t seem to be relieving at all could be a problem….
@alrman gave instructions on how to switch sticks to excavator controls by making up new connecting rods down to control bank)??? I would like to read this got a link???
I don’t know how to send a link from my phone, but the title of the thread in here was Going from CASE controls to 2 lever wobble stick and it aint pretty! It was started on 18 August 2012. Maybe you can search for it?
Look HERE
Switch the hoses to the valve/control be easier?
No switching hoses won’t work. The relief valves are set differently so it’ll end up messy. The modified rods are easy to make. Finding 3/8” s/s round bar in place of 10mm was my biggest challenge.