Hitachi UH122

[Welder Dave]

Looks like you found the problem. I had a similar screen in a hex fitting on my Cat that gave me fits. I wasn't sure what people were saying until one guy explained exactly where the screen was. It almost looked like it had little strips of wood in it. Machine would idle but die when I tried to move it. Took about 40 minutes to move it about 1/8 of a mile onto some high ground to work on it.

 

[etd66ss]

Just thinking about this machine as a future project and doing some initial research.

Would this machine be considered a Grey Market machine? It has a label on it that states it was built for export, so I am assuming no?

Also, it seems the UH123 vintage is when Hitachi partnered with JD, so parts for a UH123 seem to be more readily available than for a UH122. I have a UH122 parts manual and searching part numbers online reveals absolutely zero results, quite concerning (part numbers were never digitized, they reside in paper catalogs only). Is it likely the case that JD will not be able to help me at all with parts for this machine? I have yet to contact a JD dealership, but I think I already know the answer to whether or not they could help with this project.

Lastly, I have been looking into the Isuzu E120 engine. I see engine kits online for an E120, but they are all 4 cylinder kits, where the E120 I have is 6 cylinder. This makes no sense...

If the answer is to re-power & re-pump this machine, not sure I'd ever be taking it on as a legitimate restoration project, would much prefer to restore to original. I don't need the machine for any specific reason, just grabbed it because it was going to get cut up and scraped and thought it might be fun to fix up and use it alongside my CAT 225 when I dig my next pond. Excavators are pretty handy to have...

 

[Welder Dave]

Isuzu is a great engine. Shouldn't be hard to find parts. The 1st JD Hitachi machines were JD790 and I think 792. Not sure if there was a competing Hitachi machine in N. America. I know that later on you couldn't buy a EX300 Hitachi in N. America, you had to buy a JD892 instead. The JD engine wasn't as good and was mounted higher meaning the pumps had to work a little harder to draw the fluid up.

 

[etd66ss]

Isuzu is a great engine. Shouldn't be hard to find parts. The 1st JD Hitachi machines were JD790 and I think 792. Not sure if there was a competing Hitachi machine in N. America. I know that later on you couldn't buy a EX300 Hitachi in N. America, you had to buy a JD892 instead. The JD engine wasn't as good and was mounted higher meaning the pumps had to work a little harder to draw the fluid up.

I see that 6RA1 engines are listed alognside E120 engines, they have the same bore & stroke.

Anyone know if the parts interchange between the two?

 

[Welder Dave]

Is there an Isuzu distributor you could contact? Just because you can't find parts online doesn't mean they're hard to get. What about talking to a Hitachi dealer? UH121, 122 and 123 were extremely popular machines. I think the UH20 used 2 of the same engines.

 

[Tones]

Is this any help? https://nl.aliexpress.com/item/1005...2&afSmartRedirect=y&gatewayAdapt=glo2nldhelp?

 

[etd66ss]

Is there an Isuzu distributor you could contact? Just because you can't find parts online doesn't mean they're hard to get. What about talking to a Hitachi dealer? UH121, 122 and 123 were extremely popular machines. I think the UH20 used 2 of the same engines.

I have emailed a local Hitachi dealership to inquire about how much support I can expect on this machine. Will be interested on what they say.

 

[Welder Dave]

How about Isuzu? I find it's better to go in person or call and talk to somebody when possible. E-mails have a tendency to get get ignored, missed or lost. Not always though. Some keep up on their e-mails. Hopefully you can get the parts you need easily.

 

[etd66ss]

How about Isuzu? I find it's better to go in person or call and talk to somebody when possible. E-mails have a tendency to get get ignored, missed or lost. Not always though. Some keep up on their e-mails. Hopefully you can get the parts you need easily.

Worth a try, the closest dealer to me is this place: https://www.conwaybeam.com/locations/buffalo-ny/

I guess I'd be worried that a truck engine is not the same as an engine for an excavator, especially the injector pump etc. These days, people at dealerships don't really want to go out of their way to help with anything other than vehicles listed in their current database as they are not going to want to be liable for any parts incompatibilities. However, if I was to overhaul this engine someday, I'd prefer NOS parts from Japan and not aftermarket from China...

This place seems to be an Isuzu engine distributor: https://www.pennpowersystems.com/engine-remanufacturing.php

However, they look like a corporation setup to deal with companies via service contracts and not a parts counter for individual Joe Schmoe's etc...

 

[Welder Dave]

I think you need to find an industrial Isuzu dealer not a truck dealer. Two different divisions. Maybe a shop that builds generators with Isuzu engines. I don't think it will be that hard to find OEM parts. The engines were/are very popular. Hopefully the Hitachi dealer gets back to you.

I just looked on Google under Isuzu industrial engines. They have a US head office in Michigan and list all their dealers. There looks to be some other authorized dealers too.

 

[etd66ss]

I think you need to find an industrial Isuzu dealer not a truck dealer. Two different divisions. Maybe a shop that builds generators with Isuzu engines. I don't think it will be that hard to find OEM parts. The engines were/are very popular. Hopefully the Hitachi dealer gets back to you.

I just looked on Google under Isuzu industrial engines. They have a US head office in Michigan and list all their dealers. There looks to be some other authorized dealers too.

Yeah, I used that website to find the Penn Power Group website. Looks very corporate.

 

[Welder Dave]

What does that mean? You're looking for parts so if they can get you the parts should be all that matters.

 

[etd66ss]

What does that mean? You're looking for parts so if they can get you the parts should be all that matters.

Meaning they are willing sell to an individual via credit card orders.

 

[skyking1]

Why are you thinking repower and re-pump? Is it all shot to heck?
Sounds like get some parts and fix the fueling issue, and keep checking it out.

 

[Welder Dave]

Meaning they are willing sell to an individual via credit card orders.

Is that a problem? Maybe there's a local shop that could bring the parts in but they could cost more. I wouldn't be thinking everything is shot just because the engine needs some work.

 

[etd66ss]

Why are you thinking repower and re-pump? Is it all shot to heck?
Sounds like get some parts and fix the fueling issue, and keep checking it out.

It was mentioned early on in this thread the the engine and pumps for this machine are obsolete and that a re-power and/or re-pump would be more economical.

I helped my brother get a Koehring 6608 operational recently and we actually had to take a heat damaged variable displacement main pump drum to a local machine shop to get it re-faced and have a new wear plate laser cut out of 4140 that was thicker than the original and then heat treated and ground so the overall height of the assembly was the same as the non damaged assembly. It was impossible to find parts for the main pumps. We could not even find a parts manual for the pumps.

At this stage I'm not saying the engine and pumps are no good in this UH122, I am just trying to do a pre-project evaluation to see if parts for this machine are as impossible to get as that Koehring.

It does seem like there are parts available for the E120 engine, at a minimum, Chinese aftermarket from places like FridayParts. Investigating whether or not I can get OEM I think is worth it as I prefer OEM to China etc.

I have not done research on the pumps yet, I only know that the parts manual I bought for the UH122 does not break down the pumps and I have yet to find a parts manual for those.

All the hyd pumps, motors and vales on this machine are Kawasaki and they do not have parts breakdowns in the manual I bought.

 

[Welder Dave]

OEM engine parts are likely readily available. You really need to get in touch with a long term Hitachi dealer that knows the UH machines from the 80's. I would think there's a lot of them in equipment salvage yards too. They were the most popular machines by a big margin back in the day.

 

[etd66ss]

You really need to get in touch with a long term Hitachi dealer that knows the UH machines from the 80's.

Yes, I think this is the key. I have a 1971 Pettibone Extendo 88 that is quite impossible to get parts for, I did find a place that has experience with those machines: https://www.landmarkequipment.com/products/pettibone/

However parts are still impossible to get, you have to get lucky finding machines that are being dismantled.

From my understanding there would not be a Hitachi dealership that knows the older machines because John Deere took care of the North American distribution back then and they just stopped doing that just a few years ago?

I have been following this guys EX120-2 project to see what kinds of problems he has with parts:

However I think he will have an easier time getting parts for an EX machine as opposed to a UH machine...

 

[Welder Dave]

The UH machines were extremely popular and I don't think all Hitachi machines were part of the deal with JD. For sure the UH20 wasn't. I'd think there must be some dealers from back in the day still in business. Even when the JD deal took effect the many UH machines still operating needed parts and service. Although newer, smaller machines like the EX120 weren't nearly as popular as 200 size machines like the UH122.

 

[Timneh1952]

Along with this thread: D65S-6

I also have the opportunity to get a Hitachi UH122

View attachment 284555
View attachment 284556
View attachment 284557View attachment 284558

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 impossibl

If I get it running I'll try to take measurements to measure the pin wear. Seems like there is a lot of internal wear.

Good morning i have a uh123 parts are hard too find you have too contact vendors in China they have what I needed for the final drive which I rebuilt one side check that oil don't run it without checking them and any leaks stop.I now have the drive motor apart that's the next rebuild.Diesel Dave helped me a great deal with his knowledge