Hydraulics on KB2475 getting extreamly HOT

[Streetglide09]

Ok I'm a newbie, I've been looking in the Hydraulics Forum and haven't been able to find anything as of yet so here is my question I have a CK30HST with 12 hours on it and been using the backhoe mostly, It seems to work fine but after about an hour or so I start to smell odor of grease/hydraulic oil and the cylinders on the boom and dipper are very hot almost to the point of not being able to lay your hand on them for very long. I've checked the other cylinders and they seem to me to be normal warm but not hot. I've looked for leaks and checked the level of hyd oil and all seems to be normal. I called my local dealer where I bought the tractor and after the 3rd guy that I talked to said he has no clue and to just run it as long as the hoe doesn't hick-up. My thing is this I don't want to burn anything up.
The dealer said it shouldn't hurt anything and they would look at it when I bring it in for the free 50hr. service. I just wish they weren't so far away (50 miles)
If anyone has any suggestions I would greatly appreciate it.
Harley.

 

[J_J]

If the cyl are bypassing, the cyl will heat up. Leaky piston seals.

Do a cyl test and a pressure check.

Does you relief valve work with those two hot cyl.

Do you have any restrictors in your BH hyd.

If you use an heat gun, you can see where our hot spots are.

 

[Tx Jim]

Does tractor have an hyd oil cooler & if so is it clean? I think the over heating problem could possibly be either a faulty relief valve or possibly HST trans if trans is being operated. I think the service department needs address overheating problem as excessive heat is detrimental to hyd seals & system.

 

[Farmerford]

Streetglide09:

There is probably nothing to be concerned about. If you put your hand in 140 deg F water you will suffer second or third degree burns in about 5 seconds; 140 deg is the temperature of hot water coming directly from typical residential water heaters. So it sounds like your cylinder is well under 140 deg F.

The temperature at which hydraulic fluid begins to rapidly oxidize or becomes too thin to provide adequate lubrication varies with composition, viscosity, and brand, but 165 deg F is a commonly accepted temperature for even generic fluids. The best place to take the temperaure is at the junction block where the FEL and/or backhoe are plumbed into the hydraulic system.

You are probably a much better backhoe operator me, but even so I suspect much of the time the dipper and boom circuits are activated they are under a load that causes the relief valve to bypass, which quickly heats up the fluid in the reservoir; the common technique is to give the dipper full flow and then raise the boom as needed to prevent the dipper from stalling. If the operator is too agressive, as I often am, both the dipper and boom stall often, causing the relief valve to open.

That activity, plus the hydrostatic transmission, puts lots of heat into the fluid; I realize that you are not moving all the time, but in most cases you move every few minutes, and even when the transmission is in neutral heat is being generated by the supply circuit for the transmission pump.

If your fluid is, say140 deg F, fluid flowing into the boom and dipper cylinders regularly should raise the metal temperature to say 120 deg F after an hour or so of use. The bucket and swing cylinders are cooler probably because they are activated a relatively shorter time than the boom and dipper cylinders.

JJ's suggestion to get a temperature gun and determine the exact temperature of each surface is a good one to determine if there is really a problem.

Please keep us posted. What you find out will help us all.

 

[Streetglide09]

Thanks guys I will check all these things. I might just be over acting but spending this kind of money just makes me concerned. If I come up with anything I will post the results. and again thanks for all the help.
Harley.

 

[CJONE]

Farmer hit the nail on the head. A general rule of thumb is 100 deg over ambient temp. So on a 100 deg day a system running hard would see almost 200 deg in spots. It is not preferred to see temps that hot but it does happen. Sundstrand used to suggest that as a guideline so don't flame me too bad. In the summer it is not uncommon not to be able to touch hydraulic components. A heat gun or res. temp indicator is really the only good way to tell. I have seen many time units get so hot they discolor paint and melt plastic pieces out of filter heads. THEN you know you have a problem!! CJ

 

[J_J]

Streetglide09 ,

Excerpt from Eaton Hyd:

Temperature
To obtain optimum service life from
both the oil and the hydraulic system,
operate between 49C (120F) and
54C (130F). The maximum oil
temperature normally recommended
is 66C (150F).

 

[Coyote machine]

I thought I posted to this thread already but I must have forgot to hit, 'post quick reply'.:confused2:
AQnyway, I don't know if the CK series allows or provides for routing of the hoe's return line directly into the hydro fill port like on the DK series, but if that is a possibility then by all means contact your dealer and ask them to do the 'kit' which I know does come with the 2475 hoes, and many dealers don't make a point of installing them on the tractors for whatever reason. The kit allows for better return flow and cooler temps of operation so well worth doing it for free IF it is able to be fitted to the CK series like it is on my DK.
Post back results; and I'm sure others may chime in with the answer to the question of the kit's fitment on CKs.
This would solve your 'excessive' heat issue for sure, assuming there is excessive heat or some other fluid flow issue to begin with....

 

[davrow]

I thought I posted to this thread already but I must have forgot to hit, 'post quick reply'.:confused2:

You are not losing your mind (at least, this does not represent an example of that). This is a duplicate post also in the Kioti section.

 

[Coyote machine]

You are not losing your mind (at least, this does not represent an example of that). This is a duplicate post also in the Kioti section.

Well that's good news; now don't do that again! I might think I've lost what's left of my mind?!:laughing:

 

[puckgrinder85]

Its probably normal after an hours worth of work, definitely check the real temperature before jumping to conclusions. I smell hydraulic smell after an hour or two of loader work when doing timber type work too.

 

[J_J]

How about telling us the actual temp.

You might want to check your filters and relief valves.

I would try and stay around 175 degrees or below.

 

[Streetglide09]

Thanks for all the input guys, I took the tractor back to the dealer a week ago and they took it out and used the hoe for 3 hours and said it did get hot but not to a point of worrying about. ( I haven't gotten a heat sensor gun to check the actual temp yet) and yes Coyote they did as you have stated put a return on the Hydro fill and a cap plug on the fill with a breather on top of Hydro, said that would help to keep heat down some. They also told me not to be afraid to use it but not to abuse it either. They said when the paint on the cylinders start to burn, to worry. (warrantee will cover it, I just hope they are true to their word).
Brought it home on Friday, and Saturday morning used the hoe pretty hard for about 4 hours and cylinders didn't seem to get as hot and another thing I noticed is it seems to have more gusto.
Then I had a Flubb of my own stupidity got off of the hoe and when I stepped to get back on hoe I stepped on the out-rigger broke the hose fitting, so thinking no big deal took the hose off and when I did the hose side of the nipple was stripped. called NAPA auto they said they could make me a new hose and should have the nipple fitting that screws into the block on the cylinder. when I got there no problem on the hose just didn't have the fitting. So I figured I would just have to wait till today and stop at a local Hydraulic shop since we have a few with all the natural gas work going on around here, and low and behold to no avail they didn't have anything, said it was metric. So I figure I would go to the local Kubota dealer and see if they might possibly have one since they are both Orange (LOL) and he goes and looks and said "no luck" asked what it went to and I told him out-rigger cylinder on my CK 30 Kioti and he had the nerve to tell me that's what I get for not buying American. since when is Kubota American?
I looked up the part # 6004-0205 which says NIPPLE, PF1/4, O-RING x 1/2-20 UNF. from these #'s I take it these are SAE thread.
I'm off work tomorrow for a rain day so I guess I'm gonna take a 100 mile ride to the dealer to get a handful of these nipples.

Thanks again guys for all the help.

 

[Streetglide09]

Here are some pictures of the Hydro bypass kit the dealer put on.