L48 or L4610?

johnjc · Feb 10, 2002

Re: L48 Loader Problems

Tags
Overall I like the L48, anything bigger and I would have to keep a dump truck and 3 axle trailer. Also if you don't have one you would need a CDL
The HST is nice for most things but when you are digging with the loader it is almost impossible not to spin the wheels and the wide fenders preventing you from seeing the tires makes it worse. My ground is shale and I have some nasty cuts and abrasions on my tires from the wheels spinning on the sharp stone. This might not be as bad if the loader lift/curl worked better.
I fill the fuel tank (13 gal.) and take 2 - 5gl cans with me for the weekend (about 16 hr). Thats a bit more than my Case 580 uses.
The fluid, filters, and oil for the 50 hr checkup were $225 and I didn't use Super UDT.
That comes to about $3 per hr for consumables. Guess that's not to bad if are getting $50 an hr. to run it .
If Kubota would get in gear and come up with a fix for the loader I would like it a lot better. If you have any questions feel free to ask
John

Tags · Feb 10, 2002

Re: L48 Loader Problems

Johnjc, I am suprised that they haven't figured out your problem yet and it seems like they keep your machine at the dealer awfully long ,not to say they aren't doing their best but a letter to Kubota may help,the squeaky wheel gets the oil.That also will be solid documentation of your problem. I have had many Kubotas and still do,and the dealer has always stood behind any problem I've ever had. I'm very interested in the outcome, this way if I buy one I'll know what to look for and how to address it.Thanks!

JATO_RaT · Feb 10, 2002

Re: L48 Loader Problems

John, I already have 50 plus hours on my L48. I've been using it hard but keep the RPM's at about 2000 or less. I changed the motor oil at 49 hours but have yet to do the hydraulic and front axle. I got the set of filters for the tractor at no charge from the dealer. The oil was 25.00 per 2.5 gallons for Super UDT. It takes 54 quarts for the hydraulics. The next change isn't until 400 hours, although the filters (all 3 of them) get changed at 200 hours. I'll probably change it in the next few days. I'm still curious about the spool valve so please keep me informed as to what the final result is. I have been able to use my tractor completely but find the inability to have full power for dump slowing me down. I figure that I am some where around 800 yds of material cut and moved. The tractor has 56 hours on it, all moving dirt. With all the loads on the tractor, I am getting around 8 to 9 hours before I'm empty on the tank. I figure with the toothbar on the bucket, I can get about 20 to 22 cu ft of dirt with each fill. The loader picks it up easily. I still have the dump problem which is only a problem when trying to position the bucket for back scraping. It sounds like the bypass for the hydraulics kicks in the minute I touch the dump position. The sound comes from the spool valve and not the hydraulic leveler. Let me know what the final results and fix are. Thanks, Rat...

Tags · Feb 11, 2002

Re: L48 Loader Problems

Rat, just thought I would pass this on....I have been told on two seperate occasions by two different Kubota dealers that it is not esential to change the hyd. oil unless there has been a contaminate i.e. water,dirt,or metal (if a cylendar lets go) if that is true or not I'm not sure ,maybe somebody here could shed some light......

kubmech · Feb 11, 2002

Re: L48 Loader Problems

Not looking to start another "fluid" war, just want to share what I've heard/read about the muli-visc. oil that UDT/super UDT is supposed to be. Some manufacturers like to use the mono viscosity oil because it tends to hold up for longer periods in the HST system. ( just to add to the confusion, read the back of the UDT container and see what you can use it in and what types, some of these are "mono's") They claim that the added pressures used in the HST system tend to break down the multi's in a shorter amount of time, hence the need to change them more often.
The debate rages on and on, on this board as well as in the shop. I think that many dealers while draining the fluid at the recommended interval look at that "nice clean" oil and think "man what a waste" but just because the oil looks good does that mean that it is? Now I'm far from an expert on this topic so I tend to lean toward the safe side and follow the recommended intervals the engineers came up with. It's tough to get a straight answer from Kubota (The "trade secret" answer is always popular)/w3tcompact/icons/tongue.gif on many of the questions that come up. So until I see some documentation saying ignore what the book tells you to do...................
I recommend following the book.

MarkV · Feb 11, 2002

Re: L48 Loader Problems

Kubmech,

I know there has been mention of services that will analyze oil for a small fee. I remember MarkC----big surprise----talking about this at one time. It would be interesting to take a new UDT sample, one from a 50 hr first change and a sample from 200 hours to see the difference. For the price of UDT I would expect some kind of magic mixed in there somewhere./w3tcompact/icons/smile.gif

With the money I have in my tractor I just do what they say to do.

MarkV

kubmech · Feb 11, 2002

Re: L48 Loader Problems

Mark, one of the cool things about TBN is you guys get to play around with certain things more than I can. Any idea where that info from Mark C is?

johnjc · Feb 12, 2002

Re: L48 Loader Problems

Got back in town in time to stop by the dealers and check on my tractor. The manager is out of town, on a cruse they told me. So I talked to the mechanic. It turns out that the new valve is not a leveler valve but the front distribution block. Told me that the old one was losing pressure after it got hot. The new distribution block looks the same but has a different part number.
So currently we have a new front distribution block, the hydraulic leveler valve reinstalled (at Kubota request) and all the pressure adjustments set at the high end of their range as read from the rear backhoe hydraulic coupler. So that the loader pressure will benefit from any drop in the system.
I ask the mechanic why the pressure gage they were going to install wasn't mounted and he said they didn't tell him to mount it. Went to the salesman and he looked but couldn't find it. Said they would look and put it on if found.
When talking to the mechanic he told me that Kubota wanted the gage installed back by the backhoe hydraulic coupler. That doesn't make any sense to me, with open center valve there shouldn't be any pressure back there when you operate the loader. Also you wouldn't be able to see it when running the loader. Guess I'm missing something.
I will pick it up after work tomorrow and weather permitting test it this weekend .
John

kubmech · Feb 13, 2002

Re: L48 Loader Problems

John, you're not missing anything, if the gauge is hooked into
the backhoe coupler you're not going to read loader pressure.
He may have been "confused" with the procedure for checking "system" relief pressure according to the service manual. If you hook the gauge between the hyd. block and the loader valve you will STILL be reading "system" pressure. If you really want to know where you're losing pressure you need to hook a gauge into the loader circuit, like boom lift, bucket curl or dump respectively. Even then I think you're going to find that they are giving you system relief pressure. I think, if I understand how the self level valve is working, you are going to find that the back pressure applied to the opposite side of the cylinder due to the "low pressure' relief and shuttle valve in the self levelling valve are working against each other in your old self level valve. I'm hoping that the new self level valve they installed is going to solve this problem, somewhat, the problem that Rat describes, with the dump circuit fighting relief and slowing things down is still going to be there. I really wish Kubota would just throw in the towel, provide a mechanical self level linkage (or talk to their Wheel Loader engineers, that system works fine) and stop using you guys as a "Test Bed".

JATO_RaT · Feb 13, 2002

Re: L48 Loader Problems

Thanks for the information Kubmech. To answer a few messages left while I was out.

I changed all the oils for the 50 hours maintenance as Kubota recommends. The hydro flyuid while certainly not dirty, was full of micro metal particles dispersed throughout it. They are so fine that the only way to see them is when the oil is held in the light a certain way. The 2 hydraulic filters were pretty clean but the hydrostatic filter was pretty full of metal particles. I may even consider replacing it at the 100 hour mark even though it calls for it at 200 hours. The front axle got Amsoil 30 because its what I had left over from another tractor and the dealer was closed so I could not get any Super UDT which is what appears to have come out of it. The hydraulic amount total was 49 quarts. The manual says 53.9 quarts but the lift cylinders etc eat up some of that.

The hydraulic leveler is still a concern, but not really all that hindering. Kubmech, is there any pressure relief in the loader control valve/spool? I can hear from the spool, a sound of tshhhhhh whenever I dump, whether its empty, full or in mid air with no loads. It sounds like it is supplying just enough fluid to allow the the bucket dump cylinders to extend while bypassing most of the pressure back to the tank. I believe the problem is an extend or bucket dump pressure problem for me. The problem that John is having seems to be a little more extensive. Since I do not have a hoe but have run the loader and TNT for 5 to 6 hours on end to the point where metal hydro lines and valves are very hot with no apparent loss in abilities. Anyway, I will continue to pursue it and any info I get will gladly be passed on.

P.S. My local dealer (I did not buy from him) says no problems with any of the L48's he's sold to any customers yet. He has sold alot of L48's with lots of extras. They do some great custom work for the customers and seem to have hydraulics down very well. Its just hard to milk him for info since he now knows I did not purchase my L48 from him.

Rat....