appalachian1911
New Member
I recently acquired a used Komatsu PC38UU-1. Engine runs very well. But it has some hydraulic issues.
Backstory time!!
So I Purchased this unit a few weeks ago. It had been sitting for somewhere around 2 years due to what the previous owner thought was a bad right side walking motor. Previous owner supposedly installed a new 3 stage hydraulic pump and when that didn’t fix the issue he decided it was the walking motor it’s self and parked it and bought a new kubota…
So I come along and end up purchasing it… I believe he was as upfront about its issues as he could honestly be. I was told it needed the walking motor and a new exhaust manifold and that some of the hydraulic functions are weak. I started the machine, which started, idled and ran very well. Engaged the left side track and it moved both directions as it should. Engaged the right side track and it moved maybe a couple inches then stopped. When it stopped you could hear the engine lug down a little like it was under load. Interesting. So after messing around with it I discovered The left track, swing, and boom work as they should. Plenty of power and speed. Now on the other hand… the right track (believed to be walking motor issue), bucket, stick, and blade are painfully slow to move and stop moving when met with little resistance… also the high speed pedal seems to have little to no effect…. Also interesting. So me being me I bought it and they even delivered it for free to my property….
Now here’s the current situation!
I limped it up the drive way and parked it at the house and stared at my new to me headache. Went ahead and bought a walking motor and installed it like an idiot without checking anything else really… and after fighting it almost all day I finally got it installed and the hydraulic lines connected correctly. Jumped on with my hopes high (way to high to be exact lol) and same thing. Right track will NOT move on it’s on either direction… So after going half blind from searching the internet (with very minimal success of course) and even less success from “local” komatsu dealers.. I’ve found my way here in hopes of finding some information on this specific machine and hopefully which direction I need to go in order to get this thing fully functional. I’ve narrowed it down to a few possible problems. The first is simple, I honestly don’t think the strainer in the bottom of the hydraulic tank has ever been changed… The reason this is first on my list of possible issues is.. When I pulled the hydraulic filter under the cover on the top of the tank I immediately noticed some material that appears to be like metal dust/goop on top of the filter. Possibly material from the original hydraulic pump failure? Which brings me back to the POs claim of installing a new pump. Which the pump housing is definitely cleaner and newer looking than other components…. I currently have no way to test the flow or pressures on the output side of the pump… but can obtain it if decided that’s the next step… But anyway… So I pulled the plug to drain the hydraulic fluid and noticed the plug is magnetized and has some metal material on it as well… not a huge gob or large pieces. The best way I can explain the material found on the top of the filter and magnetic plug is it’s all similar in size to tiny grains of sand… So I’ve got a new strainer filter in the mail…
If the new strainer filter and hydraulic filter doesn’t make a difference in performance where should I focus my efforts? Should I obtain the equipment to pressure test the pump? Or should I remove, disassemble, clean and inspect the valve body? Or should I just jump in the pond with my pockets full of rocks..? Just kidding!!!! I’ve got nearly 10 years experience as a field mechanic for an extremely large clearing and construction company. But I’ve never really worked around anything of this age before… which leads me to my next round of question lol. Can anybody help me identify the year of this machine?
Model: PC38UU-1
Serial: 1631
Engine Model: 3D84-16A
I believe it to be a mid to late 80s year model but I’m not positive.
Any information would be extremely helpful.
Pointing me in the direction of some manuals would be AWESOME…. Any manuals at all. Parts manuals, owners manuals and the holy grail would be a service manual lol
Also how similar in design and equipment is PC38UU-1 to other models? Such as the PC50UU-1? Just genuinely curious.
Last question… I swear! In the cab on the right side at the floor kindly below the instrument panel is a lever with two notches. Lever is currently stuck in the top notch which is the highest position. I am unable to move the lever into the lower position/notch for some reason.. I’ve yet to really investigate. But I believe that lever is what changes the pattern of the controls? I could be wrong. But according to the extremely vague and confusing sticker on the lower right cab window it has patter A and pattern B…. I’m unable to find anything about this mystery lever.
Sorry for the long first post… I’d greatly appreciate any help and will gladly return the favor any chance I get.
Thank you!
Backstory time!!
So I Purchased this unit a few weeks ago. It had been sitting for somewhere around 2 years due to what the previous owner thought was a bad right side walking motor. Previous owner supposedly installed a new 3 stage hydraulic pump and when that didn’t fix the issue he decided it was the walking motor it’s self and parked it and bought a new kubota…
So I come along and end up purchasing it… I believe he was as upfront about its issues as he could honestly be. I was told it needed the walking motor and a new exhaust manifold and that some of the hydraulic functions are weak. I started the machine, which started, idled and ran very well. Engaged the left side track and it moved both directions as it should. Engaged the right side track and it moved maybe a couple inches then stopped. When it stopped you could hear the engine lug down a little like it was under load. Interesting. So after messing around with it I discovered The left track, swing, and boom work as they should. Plenty of power and speed. Now on the other hand… the right track (believed to be walking motor issue), bucket, stick, and blade are painfully slow to move and stop moving when met with little resistance… also the high speed pedal seems to have little to no effect…. Also interesting. So me being me I bought it and they even delivered it for free to my property….
Now here’s the current situation!
I limped it up the drive way and parked it at the house and stared at my new to me headache. Went ahead and bought a walking motor and installed it like an idiot without checking anything else really… and after fighting it almost all day I finally got it installed and the hydraulic lines connected correctly. Jumped on with my hopes high (way to high to be exact lol) and same thing. Right track will NOT move on it’s on either direction… So after going half blind from searching the internet (with very minimal success of course) and even less success from “local” komatsu dealers.. I’ve found my way here in hopes of finding some information on this specific machine and hopefully which direction I need to go in order to get this thing fully functional. I’ve narrowed it down to a few possible problems. The first is simple, I honestly don’t think the strainer in the bottom of the hydraulic tank has ever been changed… The reason this is first on my list of possible issues is.. When I pulled the hydraulic filter under the cover on the top of the tank I immediately noticed some material that appears to be like metal dust/goop on top of the filter. Possibly material from the original hydraulic pump failure? Which brings me back to the POs claim of installing a new pump. Which the pump housing is definitely cleaner and newer looking than other components…. I currently have no way to test the flow or pressures on the output side of the pump… but can obtain it if decided that’s the next step… But anyway… So I pulled the plug to drain the hydraulic fluid and noticed the plug is magnetized and has some metal material on it as well… not a huge gob or large pieces. The best way I can explain the material found on the top of the filter and magnetic plug is it’s all similar in size to tiny grains of sand… So I’ve got a new strainer filter in the mail…
If the new strainer filter and hydraulic filter doesn’t make a difference in performance where should I focus my efforts? Should I obtain the equipment to pressure test the pump? Or should I remove, disassemble, clean and inspect the valve body? Or should I just jump in the pond with my pockets full of rocks..? Just kidding!!!! I’ve got nearly 10 years experience as a field mechanic for an extremely large clearing and construction company. But I’ve never really worked around anything of this age before… which leads me to my next round of question lol. Can anybody help me identify the year of this machine?
Model: PC38UU-1
Serial: 1631
Engine Model: 3D84-16A
I believe it to be a mid to late 80s year model but I’m not positive.
Any information would be extremely helpful.
Pointing me in the direction of some manuals would be AWESOME…. Any manuals at all. Parts manuals, owners manuals and the holy grail would be a service manual lol
Also how similar in design and equipment is PC38UU-1 to other models? Such as the PC50UU-1? Just genuinely curious.
Last question… I swear! In the cab on the right side at the floor kindly below the instrument panel is a lever with two notches. Lever is currently stuck in the top notch which is the highest position. I am unable to move the lever into the lower position/notch for some reason.. I’ve yet to really investigate. But I believe that lever is what changes the pattern of the controls? I could be wrong. But according to the extremely vague and confusing sticker on the lower right cab window it has patter A and pattern B…. I’m unable to find anything about this mystery lever.
Sorry for the long first post… I’d greatly appreciate any help and will gladly return the favor any chance I get.
Thank you!
