Hydraulic level check and boom removal safety

[MJE]

I recently bought a Hitachi EX 120-3 and flushed the hydraulics. When checking the hydraulic fluid level should the bucket be extended out or curled in?

I need to remove both boom cylinders for rebuild. Any safety tips or advice as to how the machine should be positioned/blocked before the cylinders are removed? I am aware of the need to release pressure before cracking the hoses. Any guidance welcome.

thanks

 

[BigWrench55]

Bucket should be curled in. I don't know what you have at your disposal to help you with the boom cylinders. I only do one at a time. I position the machine so that I can lower one cylinder onto the track. I use a block to keep it level and I remove the rod. And I leave the barrel on the machine.

 

[skyking1]

boom and stick extended and bucket curled up towards you. That is also a great position to remove the cylinders.
I just did this on my JD120 of similar vintage. I also removed the boom for line boring.
Get the proper caps for your boom lines.
I drove the upper pin to one side to get the top loose on one cylinder as @BigWrench55 suggests, lay down that one, unhook and cap lines, remove the lower pin and get that cylinder out of the way. I had a forklift and a strap to use for the lifting. The cylinder will not lay down all the way and interferes, so I set the end on a ladder before it gets bound up. Then I rig it for picking, get a little pick on it, and take out the lower pin. The end of the pin was threaded to use the same cross-bolt to help you pull it out.

 

[MJE]

Thank you both for your response. I must admit when I first read your advice on removing one boom cylinder at a time I was stumped given they share a common pin. After looking at the machine I see there is lock pins on either side of the common pin…it makes sense now. I also looked at the bottom pin and while covered in grime it looks like there may be threads to help remove it. I do have a tractor that can help with the removal. Thanks again!

 

[MJE]

If the boom and stick are extended and the bucket is curled in and on the ground, can both boom cylinders be removed at the same time without issue? Or is there additional support of the boom needed?