Hydraulic Thumb question Re: Yanmar VIO35-3

[Dougster]

Quite a while back now, I purchased a third-party hydraulic thumb for my Yanmar VIO35-3 mini-excavator. It has worked out reasonably well for a third-party stick-mounted thumb and I saved a ton of money over the dealer's TAG/Yanmar "pin-mount" hydraulic thumb. But now I have a question that no one seems to be able to answer.

The TAG-manufactured hydraulic thumb for the VIO35-3 could be bought two ways:
1) From any TAG Manufacturing dealer, or,
2) From a Yanmar Construction dealership.

When purchased from a TAG dealer, cost was lower but no Yanmar relief valve(s) was/were included.

When purchased from a Yanmar dealer, cost was much higher, but relief valve(s) was/were supposedly included.

Or so I was told by multiple dealers and mechanics at the time.

Fast forward to last week. I've been running my third party thumb without any added relief valve(s) at close to 3,000 psig peak... but upon close review of the 3rd party manufacturer's website, I now find that 3rd party manufacturer says only run thumb at no more than 80% of cylinder design (2,400 psig). Okay, I think I really should add those Yanmar relief valve(s).

My original Yanmar dealer is out of business of course... so I call the closest alternate dealer. He knows nothing about any thumb relief valves. Call second closest alternative dealer and he answers likewise. Call third dealer and he also knows nothing. Can't get hold of Yanmar Construction directly. Just get an endless circular automated phone system with no humans attached.

Help!!! Does anyone know anything about this relief valve (or relief valves) that Yanmar dealers previously said needed to be added with the installation of a hydraulic thumb on the auxiliary circuit? Everyone seemed to know about it a year or so back... now no one knows anything. It does not show up in the VIO35-3's parts catalog or O&M manual.

Thanks,
Dougster

 

[willie59]

Is your auxilliary control valve the factory valve section? Or an auxilliary control valve that was added to the machine? If it's the factory section, you probably are referring to a circuit relief valve cartridge in the aux valve section, that's what you need to ask for. For that matter, are you certain that cartridge is not already in your aux valve section and it's just set high at 3000 psi?

Try calling Dominion Equipment Parts in Virginia for your Yanmar parts.

http://www.dominionequipmentparts.com/

 

[Dougster]

Is your auxiliary control valve the factory valve section? Or an auxiliary control valve that was added to the machine? If it's the factory section, you probably are referring to a circuit relief valve cartridge in the aux valve section, that's what you need to ask for. For that matter, are you certain that cartridge is not already in your aux valve section and it's just set high at 3000 psi?

Try calling Dominion Equipment Parts in Virginia for your Yanmar parts.

http://www.dominionequipmentparts.com/

Thanks very much. I will contact those folks today.

The machine is a standard Yanmar VIO35-3 built for the US market. It is not a grey market machine. I am the second owner, but I have no reason to believe anything was ever modified other than for routine (busted hose, new tracks, etc.) repairs.

The auxiliary circuit is controlled off the control valve stack (4th valve from left). The auxiliary control valve itself has no relief (or "overload") cartridge(s) showing while other circuits do.

The implication was that the control valve stack (or some other internal circuit component) needed to be modified by the addition of one or more relief valve cartridges in order to run the auxiliary circuit at something below main system pressure. Similar Yanmar mini-excavators on lots in that timeframe with the "factory" TAG/Yanmar hydraulic thumb had no external valves or extra lines showing. Whatever was added, if anything, it was internal to the machine.

Perhaps I was fed a load of BS or it's entirely possible that these early dealer contacts were merely assuming I had a grey market machine. It's also entirely possible that I totally misunderstand what they were trying to tell me.

Dougster

 

[Dougster]

Perhaps I was fed a load of BS or it's entirely possible that these early dealer contacts were merely assuming I had a grey market machine. It's also entirely possible that I totally misunderstand what they were trying to tell me.

Dominion Equipment Parts was unable to help, but further dealer inquiries made this morning are starting to paint a picture that this (need to add new auxiliary circuit relief valves) may be a grey market-only issue. I'm about 75% convinced at this point, but won't be able go much further with it today. I think the next step will be to visit the area's largest Yanmar Construction dealership in person and see what I can find out.

Dougster

 

[willie59]

Well that's a bummer your not making good progress. I don't work with many Yanmar units, so I'm a little at a loss of who to contact. If you don't get any info from the dealer your going to visit, you might try Multi Machine in New Jersey, talk to Eric, http://www.mmmachine.com/ .They're not really a Yanmar dealer, but they work with a lot of different grey market machines and might have an idea who you could contact. If you just keep running into dead ends, you could always contact someone like Hydraulic Circuit Technology, talk to Bobby Hudson, http://www.hctkits.com/index.html , tell him what your working with and he may be able to either provide you with a relief cartridge you need. If he doesn't have the factory type cartridge for the control valve section, I'm sure they could rig you up with plan B and install aftermarket relief valves in the piping of the auxilliary circuit.

 

[upnover]

Here is a long shot if you still hit dead ends. http://www.pacifictractor.com/ these guys are in Delta B.C and I think they know what they are talking about, they even have a toll free number.

I dont think you have a grey market machine as the 35-3's were out in Canada and the USA just prior to the model 35-5. I have a 35-5 with an aftermarket Agway thumb but I couldnt tell you if the models are similar or what to look for in the relief valve issue. Good Luck

 

[Dougster]

Well that's a bummer your not making good progress. I don't work with many Yanmar units, so I'm a little at a loss of who to contact. If you don't get any info from the dealer your going to visit, you might try Multi Machine in New Jersey, talk to Eric, http://www.mmmachine.com/ .They're not really a Yanmar dealer, but they work with a lot of different grey market machines and might have an idea who you could contact. If you just keep running into dead ends, you could always contact someone like Hydraulic Circuit Technology, talk to Bobby Hudson, http://www.hctkits.com/index.html , tell him what your working with and he may be able to either provide you with a relief cartridge you need. If he doesn't have the factory type cartridge for the control valve section, I'm sure they could rig you up with plan B and install aftermarket relief valves in the piping of the auxiliary circuit.

Here is a long shot if you still hit dead ends. http://www.pacifictractor.com/ these guys are in Delta B.C and I think they know what they are talking about, they even have a toll free number.

I don't think you have a grey market machine as the 35-3's were out in Canada and the USA just prior to the model 35-5. I have a 35-5 with an aftermarket Agway thumb but I couldn't tell you if the models are similar or what to look for in the relief valve issue. Good Luck

Thanks guys. I think I'm confusing you a little. Heck, I am confused myself!

My VIO35-3 is definitely a legitimate USA market model. No doubt about that. What I learned today is that this whole "need to add relief valves" issue that I was told about may have just been the dealers covering their butts in case I had a grey market machine.

The fact is that my auxiliary circuit control valve already has two cartridge valves in it... but they are called "shut-off valves" in the Yanmar literature (rather than "relief valves" or "overload valves" as they are elsewhere). They don't look like my other cartridge-type relief valves... including a set of cartridge reliefs I bought second hand on speculation that they might fit (they didn't). Still, one Yanmar mechanic today insists that those "shut-off valves" are really my relief valves. Could this all be a mix-up over a bad Japanese-to-English translation???

I am not convinced... but it is worth checking out further. It is a plausible story. It's just hard for me to believe that Yanmar would call relief valves "shut-off valves" and thus produce this confusion!

Dougster

 

[willie59]

are you certain that cartridge is not already in your aux valve section and it's just set high at 3000 psi?

Hmm, seems someone asked that question. Bah ha ha ha

Yes Dougster, it's not unusual to see some really strange descriptions for a part in a parts breakdown. That would be great if you have your relief cartridges already installed. Do they look like they're adjustable?

Then again, I have seen cartridges (at least that's what they look like), that are shaped just like a valve cartridge, but are in fact a machined plug, to go in place of a true valve and plug the passageway. That may in fact be what you have, then the term shut off valve would make more sense.

 

[Dougster]

Hmm, seems someone asked that question. Bah ha ha ha

Yes Dougster, it's not unusual to see some really strange descriptions for a part in a parts breakdown. That would be great if you have your relief cartridges already installed. Do they look like they're adjustable?

Then again, I have seen cartridges (at least that's what they look like), that are shaped just like a valve cartridge, but are in fact a machined plug, to go in place of a true valve and plug the passageway. That may in fact be what you have, then the term shut off valve would make more sense.

Short answer: I just don't know. I had assumed that "shut-off valves" were just that... shut-off valves. Based on what the Yanmar dealers had told me and what I read in the Yanmar literature, I had no reason to question their stated function. Now I do.

Next step is to visit the area's largest Yanmar Construction dealer in person and see what I can find out there. They have not been very helpful by phone, but that is not unusual for them. An in-person visit should finally nail this question one way or the other.

Dougster

 

[MyEquipmentSale]

Dougster,
Please feel free to email or pm me you serial # and I should be able to get you an answer tomorrow. My day job is working at a Yanmar (and other products) dealership.
E

 

[stumpjumper83]

another avenue for you to try if you hit a dead in is a custom hydraulics shop. Alot of machines use bosh-rexroth hydraulics for instance. You can buy parts from yanmar, who buys them from bosh, or you can buy them right from bosh.

I got into this when I had a leaky coupler on my deere 450c backhoe. Deere wanted $275 for one set of 1" hydraulic couplers. I was able to buy 2 sets of the same type coupler from a hydraulic shop for $80 or there abouts.

With alot of the machines being manufactured out of parts suplied by other manufacturers, you can do good to shop around.

Beiler hydraulics in leola, pa is where I go when I think the dealer is on crack or can't find what I need.

 

[MyEquipmentSale]

The parts book does not show the option. You will need to get it fron TAG or Dominion.
I can get you contact infor if you are still looking.

 

[jrtraderny]

Short answer: I just don't know. I had assumed that "shut-off valves" were just that... shut-off valves. Based on what the Yanmar dealers had told me and what I read in the Yanmar literature, I had no reason to question their stated function. Now I do.

Next step is to visit the area's largest Yanmar Construction dealer in person and see what I can find out there. They have not been very helpful by phone, but that is not unusual for them. An in-person visit should finally nail this question one way or the other.

Dougster

Dougster,
All you really need is a crossover relief valve in the circuit. It will bypass oil from one side of the cylinder to the other if you shock load the thumb. You can get one for around $100 @ any hydraulic shop.
jr

 

[jrtraderny]

https://www.surpluscenter.com/item.asp?item=9-4019-50-H&catname=

Here ya go ....................
jr