I recently purchased a used Hitachi EX220LC-3 for use around our farm. There is a large amount of play in the boom base pin and would like to replace it. I do not have a service manual so I'm looking for some advice on how to safely pull this pin out and get a new one back in. Thanks, Bryon
It's a bit more involved than that, aside from the pin you will need new bushings for the boom foot and if the pin seems to be wallowing around in the fixed bores they may need to be welded up and line bored also. The last one I did years ago, I had the benefit of an RT crane in the yard. We popped the stick off, popped the boom cylinders off, removed and capped the hoses, then with the boom hanging on the hook just took the weight off the pin and drove it out. That machine had a hole in the cab as I recall for putting a drift pin through to the boom pin. I've seen this kind of repair done without separating the boom and stick but it makes me nervous.
If you have lifting gear the boom is not all that heavy. Take off the stick,disconnect the hoses,pull out the pin and lift it off. If no lifting gear I have done them by digging a deep hole. Put the bucket down deep as possible with the stick vertical. Pull the boom pin and use the boom hoist cylinders to lift the boom clear. Not the best option. Depending on the age of the digger the boom bushings may be sintered metal. I use a torch to run a melt line along the length of the bearing and after cooling they will tap out. Get the grease out of that tunnel before you put a torch in there. I doubt the bores would be out of shape. I've never line bored those on a small Hitachi in 28 years of lineboring. The bearings are a 12 to 14 thou press fit in those so you need heat and liquid nitrogen to get them in or some substantial pressing gear. Check the bores in the machine itself. They don't have bearings and are more likely to be worn than the boom bores.
RayF, that's what I was referring to was the bores on the upper frame of the machine, I agree with you about the boom bores, never seen those go egg shaped. Now the stick is a whole different world, lol.
Yes,I've probable made more than a $1.50 on stick bores and faces.
Thanks for the reply’s. I do not have any way of lifting the boom so I like the idea of burying the bucket to do this work. Any suggestions on were to purchase bushings? Should I stick with the dealer or try to look aftermarket?
If you are not in a rush I would suggest to get it all disassembled first then look at what parts you need. Depending on how much wear you find then potentially some rectification work (welding/boring) may well be called for before you can reassemble. I wouldn't go buying parts myself until I had it all in bits on the floor.
I don't know what you have there for parts. Do JD market a Hitachi machine? In that pivot you only have two bearings,two seals (boom) and a pin.
Yeah, Hitachi parts can be had at your local US Deere dealer. YMMV.