Hitachi UH122

[etd66ss]

The pumps may be dry of oil with the tank being low and where the leak is. I'd be inclined to put some oil in the tank then pressurise it with air before starting

How much oil do you think I need just to try and start? ~20 gallons?

Anyone know how much oil the tank holds? I tried to Google specs but can't seem to find. I am assuming at least 50 gallons. My CAT 225 tank holds 80 gallons. But this tank looks smaller.

The owner also has a derelict Daewoo DH220LC parked down the road a bit. I can maybe also scavenge HYD oil from that as well...

 

[Tones]

20 gallons should be heaps to get it started but probably need more after it's started and if it's a keeper.

 

[Welder Dave]

This could be a good excuse to buy some cheaper hyd. oil from a farm store or Walmart. I don't think it's a good idea to use used oil out of another derelict machine. Perhaps pressurizing the hyd. tank to 5 to 10 PSI with air would show where it's leaking.

 

[skyking1]

cut a barrel down and fit it under the swivel area.
get it ready to attempt a start.
Add oil as suggested.
Recover leaked oil to re-use.
bonus points for giving it a spray down with brake cleaner beforehand to minimize dirt in your barrel.

 

[etd66ss]

This could be a good excuse to buy some cheaper hyd. oil from a farm store or Walmart. I don't think it's a good idea to use used oil out of another derelict machine. Perhaps pressurizing the hyd. tank to 5 to 10 PSI with air would show where it's leaking.

I agree it's not the best option to use old oil, I can't really justify buying $100's worth of Tractor Supply oil that still costs $60 per 5 gal bucket before I even hear this thing fire. As it is I am buying an ignition switch and a fuel filter (~$50 total). I've already spent about $100 on this project and want to keep it to a minimum if I can. I'm told the property changes hands in a couple weeks, so I really need to at least get this thing driven back to his other lot (about 1/2 mile) so I have more time to evaluate it.

If I do have to buy oil, I'd use ISO46 oil?



In the meantime I have looked for a swivel/pivot assembly (not sure what Hitachi calls them) for this UH122 and not coming up with any seal kits. I see a lot of parts for EX machines but not the older UH machines.

Also, if I do pressurize the tank after putting enough oil in it to submerge the filter, is there a way to bleed the main pumps to make sure they don't have air pockets?

 

[etd66ss]

Well I was wrong on the capacity of the HYD tank:



100 gallons ouch.

I'm not buying any oil, we'll see what the owner wants to do. He may just decide to call the scrappers.

 

[Acoals]

Well, if the pennies are this much of a concern just jump the switch to get it started . . .

 

[etd66ss]

I talked to the owner and he's fine with me taking HYD oil from the other machines. So that's what I am going to do. In his mind they are all scrap anyways, he just wants them gone...

Is there a chance that this center joint really gushes out oil when I try to track the machine for the first time? Or is this leak most likley just a housing seal leaking due to weight of oil above it?

 

[361brock]

I described the bleed process in an earlier post.

 

[KerryLakeInc]

Along with this thread: D65S-6

I also have the opportunity to get a Hitachi UH122

View attachment 284555
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The pins, bushings & rails look to be in quite good shape. Almost like a new UC was installed and then it didn't get much use. I have no idea why it was parked, but it has been sitting for ~25 years.

Anyone familiar with these units any info is much appreciated.

I assume getting parts for this machine is about impossible?

We just bought a used UH083, parts are very difficult. Replacement head piece for travel motor from searching to receiving was about 6 weeks from Korea. Replacement seals for final drives another 3 weeks from China. And we still haven’t gotten her up and running yet

 

[etd66ss]

We just bought a used UH083, parts are very difficult. Replacement head piece for travel motor from searching to receiving was about 6 weeks from Korea. Replacement seals for final drives another 3 weeks from China. And we still haven’t gotten her up and running yet

Yes, this is a concern for sure. It seems like the UH machines are abandoned when compared to the EX machines in terms of parts availability.

So at work we have two 55 gallon drums of Mobile DTE26, which is AW68 HYD oil. Would this be too heavy an oil for this machine? We don't build HYD machine anymore some might be able to get those drums.

 

[Acoals]

For your purposes here I figure any oil will do . . .

 

[skyking1]

yes that would be great. It is only a little thick for the coldest temperatures.

 

[Tones]

For the time being 20 gallons should be enough to start the engine. If the engine is buggered then you haven't thrown to much coin at a failure.
Assuming the swivel joint is pouring oil out then you are going to have trouble moving it under its own power so formulate a plan B like pulling out the sun gear in the planetary and towing it. As for resealing the swivel joint a good bearing shop should be able to get the seals but not necessarily as a kit.

 

[etd66ss]

So, I found a rather suspect hose for the right side track attached to the center joint:



I decided to take it off to see if I can make one at work as we have a Parker Par-Krimp machine and I have made many hoses with it for my other equipment in the past.

I got one fitting off and I was letting the oil drain into a 2.5 gallon bucket. The oil just kept coming, it wasn't going to stop. This was not just residual oil in the hose. I was forced to reconnect the hose. I noticed Hitachi uses inverted flare fittings which are not common, I am betting they are metric as well.

I don't think the oil should just be draining from tank through the swivel, nor certainly a drive motor hose. Those are pressurized via a hyd piloted valve. The only things under the swivel joint are the drive motor hoses and parking brake hoses, none of them should be gravity fed by the tank. There is no way the 100 gallons should have leaked out over the last 5 years with just a leaking center joint correct?

This issue implies something else is wrong? A main valve is cracked open and not fully closed or something?

Also, all the hoses on this machine have their original brass part number tags, they seem to be all original. Googling part numbers returns ZERO results. this is not a good sign IMO in terms of a parts nightmare this machine could be. Is this essentially a grey market machine??? Were UH machines not for the North American market?

 

[etd66ss]

Anyone know if that track drive hose & fitting assembly would need to be 4000psi or 6000psi capacity?

Very huge difference in the price of the hose crimp fittings...

I don't have a HYD schematic to see what the relief valves are set at for the track motors. Parker 43 series fittings are about 1/5th the cost of the 77 series.

1GU77-12-12

1GU43-12-12

 

[Tones]

Those fittings could be BSP. They look opposite to a JIC fitting. The threads are the same though. 4000psi hose should be ok IMO. Gotta be better than fixing the swivel joint.

 

[Diesel Dave]

A Deere 792 strait , main pump pressures were 3770 PSI

 

[etd66ss]

A Deere 792 strait , main pump pressures were 3770 PSI

Ok, interesting. My CAT 225 iirc is over 5000 psi.

 

[etd66ss]

Those fittings could be BSP. They look opposite to a JIC fitting. The threads are the same though. 4000psi hose should be ok IMO. Gotta be better than fixing the swivel joint.

I think the center joint definitely needs to be resealed, but that is not a concern for right now (could be a disaster later if I do end up with the machine though...). That track drive hose looks like it's going to pop the moment I try to move this machine.

Tried to clean up the center joint a bit more tonight: