b77 backhoe question

[Kub123]

Hi All,
I bought an L3200 with a BH77 Backhoe attached to it earlier in the year. I've had to take it back to the dealership
several times with hydraulic issues (weak cylinders). Everything seems fine now, but I have a question about the
operation of the backhoe. Can the boom cylinder and the dipper cylinder operate at the same time? I didn't know if this was a kubota thing or not, but I don't think I've had this issue with other backhoes. I cannot raise the boom until I release the dipper control. I can only use either one cylinder or the other, not both. It would be nice if I could use both for "skimming" the topsoil off of a septic tank for example. The guy at the dealership said that is just the way it is. I think they are as tired of me as I am of them. Any help would be very appreciated.

 

[Donystoy]

Mine is a Woods 650 Backhoe but I have never heard of a backhoe that will not allow all actions to be done simultaneously. In fact as you probably know you have to operate more than one function at a time to achieve smooth operation. I do not think that the chap at the dealership knows what he is talking about. My boom is controlled by the left handle while the dipper is from the right handle. I wonder if you just do not have enough hydraulics to operate both at once and something is wrong there. Increase you engine speed to see if it helps. Mine has its own PTO driven pump which I run on high speed with engine at 1800 rpms.

 

[placervillebob]

I have a 2005 L2800 with a BH75, a little smaller than yours, but I can and do operate both the boom and the dipper stick hydraulics at the same time. I use them together for exactly the reason you mentioned, to skim a little from the area being excavated. If you can't operate both at the same time, the motion will result in an arch (from the dipper stick) and you will have difficulty producing a flat bottom surface. I guess I would be surprised that the BH77 was that much different than the BH75 and wouldn't give you this combined motion.
Bob

 

[Kub123]

Thanks for the replies guys.
I think I need to complain about this dealership to the higher ups.
They have been making excuses about odd things happening on the tractor.
That reminds me, I have another question. Are you able to move the boom with your bare hands from side to side after the tractor sits overnight. But as soon as you crank the engine, it stiffens back up? This happens with the front end loader bucket too. I can step on the bucket and extend the cylinder, then it will shrink back when I step off.

 

[Bulldog]

That really doesn't sound right on the backhoe. I had a 4672 Kubota hoe and I could work the boom, stick and bucket at the same time. Obviously none of the functions worked at full speed because the flow was shared by all 3 functions but they would work together. I wonder if you have a relief valve stuck and it's letting the pressure bypass.

Have you ever had the hyd pressure checked?

 

[Kub123]

Thanks for the reply Bulldog.
I've had the tractor back at the dealership several times for the hydraulic issues.
I'm assuming they have checked pressure and everything. They say they have replaced the control valves, repacked the boom cylinder and flushed the system in case of any foreign particles.

 

[IDKUBOTA]

I have the l3800 w BH77 and I can operate the functions you mention simultaneously as we'll as the bucket. In regards to the dipper stick losing some pressure, mine does a little overnight and so does my friend's with the same set up.

It would seem that you may consider trying another l3200 with backhoe at the dealership. Look on YouTube for 3200.avi. This guy has the same backhoe set up and it functions as it should. Read this guy's side comments and
Show the dealer the video.

Good luck

Idk

 

[Tarmy]

I have an 08 L2800 with a BH76A...I bought the backhoe new...and from day one I had the "weak ram" problem. We (the dealer and I) figured out that the valve had got a paint chip in it from the original assembly. Turns out this happens a fair amount of the time (fouled assembly procedure). We cleaned out the valves and it works good...not great. I do agree with the other folks that the backhoe should allow you to use more than one function at a time. Sometimes my main arm ram lags a bit when I am trying to move it a bit fast...if the revs on the engine are not above about 1700RPM. If I would have known then what I know now...I would have bitched a lot more to get the dealer to make it work correctly from the start.

 

[Bulldog]

If you're only running around 1700 rpm's you'll never be able to get the full function out of the backhoe. I never liked sitting there with the engine screaming but fact of the matter is that it's designed to operate at the rated pto rpm. Depending on the machine 2150 - 2500 rpm range. A few hundred extra rpm's makes a big difference on hyd flow and pressure.

 

[trouble11]

Try increasing the rpm,s if it still does not work, keep bugging Your Dealer.!!!

 

[Kub123]

I have to tried to increase the rpm's to no avail.
There is another kubota dealership about 45 miles away. Would I be able to take it there and let them give it a try to fix it?

 

[Teikas Dad]

I've got a bh77 on my B3200 and I can do multiple movements at the same time....I don't know what I'm doing so I still do one at a time... But, the backhoe is capable of doing it as I tried curling the bucket and gathering in the dipper arm at the same time with no problem.

 

[Bulldog]

The biggest thing I see with the Kubota BH is the operator has got to have some skill to make it work as it should. A person with limited experience is going to have a hard time being smooth. The controls really have to be feathered on each function to make them work together.
I know everything takes a certain ammount of skill but a Kubota BH requires more skill to operate than say a Cat bh would. The Cat might intimidate some because of it's size but actual operation the Cat is easier.

 

[Lil Foot]

The biggest thing I see with the Kubota BH is the operator has got to have some skill to make it work as it should. A person with limited experience is going to have a hard time being smooth. The controls really have to be feathered on each function to make them work together.
I know everything takes a certain ammount of skill but a Kubota BH requires more skill to operate than say a Cat bh would. The Cat might intimidate some because of it's size but actual operation the Cat is easier.

This is certainly true of my somewhat ancient B670- it will perform multiple functions or "combo moves", but it's very hard to hit the tiny sweet spot where both functions work at the same time, and then if you hit that spot, both functions are very slow. There are times when I take the trouble to make the "combo moves", like trying to make the bottom of a trench flat & level, but most of the time it isn't worth the effort or time. More rpm helps, but but I think the pump on mine is just too small to support multiple moves efficiently.

 

[Bulldog]

When I got my B7100 it came with no manual or instruction from the original owner. I found that when the pto was in the 3rd stage the backhoe would dig like crazy. I had no idea it was designed to run in the first stage. I figured if it had 3 stages you used which ever one worked best so when I needed more power I would just get another gear.
Keep in mind I was like 8 years old when Dad bought it, but what a cool little tractor. The BH that came with the tractor lasted about 7 or 8 yrs before I broke it beyond repair. I guess the 3rd gear digging wasn't the best move I ever made.

 

[Burt]

Hi All,
I bought an L3200 with a BH77 Backhoe attached to it earlier in the year. I've had to take it back to the dealership
several times with hydraulic issues (weak cylinders). Everything seems fine now, but I have a question about the
operation of the backhoe. Can the boom cylinder and the dipper cylinder operate at the same time? I didn't know if this was a kubota thing or not, but I don't think I've had this issue with other backhoes. I cannot raise the boom until I release the dipper control. I can only use either one cylinder or the other, not both. It would be nice if I could use both for "skimming" the topsoil off of a septic tank for example. The guy at the dealership said that is just the way it is. I think they are as tired of me as I am of them. Any help would be very appreciated.

If you keep getting stonewalled at the dealer then insist on talking with or to the factory rep. That usually gets the dealers attention. Their "franchise" is then challenged either by lack of product knowledge or training. Stay at it.

Burt

 

[BAP]

You asked wether or not you could take it to another dealer. If your current dealer is unable or unwilling to fix it properly, then try another dealer. I would get on the phone first and talk to them, tell them what is going on and see what they say.

 

[TableRocked]

Dumb question, but, would a higher GPM pump, say from an L35, L39, L45, or L48 solve this problem? I'm still trying to learn what more GPM's truly mean in getting work done.

 

[SteveF]

Dumb question, but, would a higher GPM pump, say from an L35, L39, L45, or L48 solve this problem? I'm still trying to learn what more GPM's truly mean in getting work done.

More volume and flow may enhance function but I agree with those that are thinking there is a restriction in the fluidic system here. I have to believe that the valve/control system, hyd lines & fittings, and cylinders are appropriately sized for the structural components.

The B601 on my little bx25 doesn't like to work very fast at low rpm's say under about 2,000 rpm's but at 2,500 and up has full range of motion that you have with bigger hoe's although it can be a bit jerky but that could just be me.

I did read your post on equating GPM with work and thought it was pretty much answered. GPM or flow rate is only one side of the equation needed to calculate work.

 

[olthumpa]

tablerocked:

Hopefully you have a tool rental place near you that rents and sells pressure washers. If you do, you just became interested in purchasing a pressure washer "later" this spring and want to check out your options now.

Go to the rental place and tell them what "Iam interested in purchasing a pressure washer "later" this spring and want to check out your options now."

You are interested in medium and high pressure units with interchangeable tips. Ask them for a demonstration, (after all you are going to be spending +- $1000), and to try them yourself. By changing tips on both units and trying them out, how GPM and PSI work together to accomplish work done should become readily apparent to you.

Just my two cents.