KMS 180 backhoe / backactor Metal in oil and how to fix it.

mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
aw... you 'cheated'.. I was hoping to see a full length video of you TIG welding new teeth onto the pump shaft, filling them to SAE dimensions, balancing the shaft and then reinstalling the rebuilt pump !
:giggle: :giggle:
have to admit that new pump does look a LOT better than the original, that must have a zillion revolutions on it.
I do plan to see what can be done to have that old pump as a spare...
 

mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
Small update

The hydraulic shop are making progress on the cylinders.

And the new pump has arrived.
Should I rinse it through to be sure there is no manufacturing swarf left in it?

PXL_20240104_102459467.jpg
PXL_20240104_102510085.jpg
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,716
5,067
113
Greensville,Ontario,Canada
I've never bothered ......
wow, it's too pretty to install !!!!
when you do, maybe add some 'never seize' or at least oil on the PTO splines and the C-clip.
it's an 'ounce of prevention' thing.
 
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mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
I got another unit of workshop time this weekend, while my attempts to set up the new gas bottle for the welder were put on ice due to the regulator and bottle threads both being male! This gave me an opportunity to look at the backhoe stabiliser leg tubes, which were bowed out slightly.

A look inside and I was slightly surprised by what I saw.
1704648936549.png


The bottom of the leg is full of some crud! Actually both legs!

I got this much out fairly easily, maybe 500g or so ( about a lb)
1704649009653.png


it looked better, I could see the bolt hole on the bottom
1704649086201.png


With some success, I thought to prevent future build up. To do so I drilled at 10mm hole in the bottom of the leg to let the future build up get out of there. I also thought about some kind of sealing cap for the leg to prevent the dirt and weather ingress, once it is back in service.
1704649182103.png


The only way i could think to get the last remnants was a 1metre ( about a yard) long wire brush. An angle grinder cup brush with a length of all thread.
1704649283689.png
1704649309607.png

1704649334507.png

In action cooking up a mess!
The results were a big improvment
1704649379776.png

1704649407413.png


Another few rinses with degreaser should get that cleaned up and be ready to accept the cylinders when they are ready.

The snow and cold is really stopping the work progressing faster, it is -26C ( -15F) here today.
1704649529343.png
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,716
5,067
113
Greensville,Ontario,Canada
brrr. I feel k-k-k-k-kold now !

can you spray / dribble 'rust-check' or 'oil' down those tubes before reassembling ?
 
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fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,847
5,072
113
Eastham, Ma
brrr. I feel k-k-k-k-kold now !

can you spray / dribble 'rust-check' or 'oil' down those tubes before reassembling ?
If Phosphoric acid (often called OSPHO in USA) is available in Latvia, that would be a good product to combat rust inside the leg.
 
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mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
can you spray / dribble 'rust-check' or 'oil' down those tubes before reassembling ?
I should be able to.

If Phosphoric acid (often called OSPHO in USA) is available in Latvia, that would be a good product to combat rust inside the leg.
I'll take a look and see what can be had locally.
It would make me happier to have the the rust dealt with.
 

fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,847
5,072
113
Eastham, Ma
I should be able to.



I'll take a look and see what can be had locally.
It would make me happier to have the the rust dealt with.
I would expect that Phosphoric acid can be found anywhere, though it may not be sold in the EU specifically for rust prevention.
It actually combines with existing rust to act as a sealer/primer, for painting steel, however inside those legs, it might not really need any sort of protective topcoat.
 

mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
Everybody loves an update.

I have got 5 of 7 cyclinders back from the shop, cleaned, inspected and resealed where neccessary.
I also have the valve block from the shop.

In the mean time I managed to get some time to improve the hydraulic oil tank in 3 minor ways
1. A boss for a magnetic sump stud. Although I can't see how metal will get into the tank if the filter is working properly on the return.
2. a sight level and thermometer.
3. a valve on the Pump suction line so that I can isloate the pump without losing a tank worth of oil.

Measure and mark
1706469399461.png


Nuts in place

1706469466559.png


Everything welded up.

1706469435301.png



Typically, the job was small, but there was some yak shaving to get there, building a welding trolley, buying a new weldng mask, a saga with gas bottles and regulators, a workshop rewire and a misadventure into chinese mini excavator attachments, which are so cheap but also too small for my KMS180.

With the weather heading for a short period of positive temperatures, theres is a chance to clean all the lines and get the cylinders I have fitted while waiting on the leg cylinders.
 

fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,847
5,072
113
Eastham, Ma
Everybody loves an update.

I have got 5 of 7 cyclinders back from the shop, cleaned, inspected and resealed where neccessary.
I also have the valve block from the shop.

In the mean time I managed to get some time to improve the hydraulic oil tank in 3 minor ways
1. A boss for a magnetic sump stud. Although I can't see how metal will get into the tank if the filter is working properly on the return.
2. a sight level and thermometer.
3. a valve on the Pump suction line so that I can isloate the pump without losing a tank worth of oil.

Measure and mark
View attachment 121304

Nuts in place

View attachment 121306

Everything welded up.

View attachment 121305


Typically, the job was small, but there was some yak shaving to get there, building a welding trolley, buying a new weldng mask, a saga with gas bottles and regulators, a workshop rewire and a misadventure into chinese mini excavator attachments, which are so cheap but also too small for my KMS180.

With the weather heading for a short period of positive temperatures, theres is a chance to clean all the lines and get the cylinders I have fitted while waiting on the leg cylinders.
Your updates are GREAT!
Please keep them coming!
 

mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
Another weekend with a chance to progress this project.

I managed to get the tank rinised out, degreased, and trial fitted
Here you can see the new sight guage and thermometer.
Now that I can see everything fits well, I can paint the tank.
1708849422315.png


I also got the slew cyclinders in position
1708849539377.png

I used the photos I took before disassembly to get the hydraulic lines connected in the right places
I blew the lines out with compressed air to make sure they are clean.
1708849655985.png


The arm cylinders are next for refitting and then I am still waiting on the leg cyclinders to come back from the service shop.
 
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fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,847
5,072
113
Eastham, Ma
Another weekend with a chance to progress this project.

I managed to get the tank rinised out, degreased, and trial fitted
Here you can see the new sight guage and thermometer.
Now that I can see everything fits well, I can paint the tank.
View attachment 123006

I also got the slew cyclinders in position
View attachment 123007
I used the photos I took before disassembly to get the hydraulic lines connected in the right places
I blew the lines out with compressed air to make sure they are clean.
View attachment 123008

The arm cylinders are next for refitting and then I am still waiting on the leg cyclinders to come back from the service shop.
Good progress!
 

mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
I have had a good week of progress. I fitted the arm cylinders, made a mounting bracket for the pump, got a new return hose, hose flanges for the pump bought and fitted.
IMG-20240306-WA0004.jpeg
PXL_20240306_172916075.jpg

The leg cylinders came back from the rebuild. With the arm bled and supporting its own weight i tried to drive out of my temporary workshop, but the subframe was caught on the low rise of the wall, this was made worse by the extra weight hanging from it and then due to previously only fitting one front mounting pin, i pulled the subframe off the rear mount late one evening. The next morning with a clear head and some hard thinking it was levered back into place and secured at 4 points as it should be.
IMG-20240306-WA0006.jpeg IMG-20240306-WA0008.jpeg

To refit the leg cylinders i backed over an in built car ramp which gave the clearance needed to slide in the leg cylinders.

Today i had a good shake down session, tidied up hoses, tightened leaking joints, greased where i could with the gub and my fingers where i couldn't get the grease gun in. Ill be getting a flexible head for this back actor as it has some tight spots to get grease in.
PXL_20240309_063105716.jpg
Wow this machine really digs now! The speed is ideal, the power is great and able to break through 2 inches of frozen ground when digging.

The outstanding issue is the boom cylinder has some serious cylinder drift constantly. I will have to try bleeding it again.
IMG-d5873db4097c9aa807a399973e20362b-V.jpg
I dug out 7 small cherry trees where we are planning to build a new house and re planted them in a fraction of the time it would have taken with my shovel!
IMG-d5873db4097c9aa807a399973e20362b-V.jpg
PXL_20240309_122009121.jpg
PXL_20240309_143614477.jpg
PXL_20240309_145359004.jpg
Here is to more digging!
 

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fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,847
5,072
113
Eastham, Ma
I have had a good week of progress. I fitted the arm cylinders, made a mounting bracket for the pump, got a new return hose, hose flanges for the pump bought and fitted.
View attachment 123932
View attachment 123933

The leg cylinders came back from the rebuild. With the arm bled and supporting its own weight i tried to drive out of my temporary workshop, but the subframe was caught on the low rise of the wall, this was made worse by the extra weight hanging from it and then due to previously only fitting one front mounting pin, i pulled the subframe off the rear mount late one evening. The next morning with a clear head and some hard thinking it was levered back into place and secured at 4 points as it should be.
View attachment 123935 View attachment 123936

To refit the leg cylinders i backed over an in built car ramp which gave the clearance needed to slide in the leg cylinders.

Today i had a good shake down session, tidied up hoses, tightened leaking joints, greased where i could with the gub and my fingers where i couldn't get the grease gun in. Ill be getting a flexible head for this back actor as it has some tight spots to get grease in.
View attachment 123937
Wow this machine really digs now! The speed is ideal, the power is great and able to break through 2 inches of frozen ground when digging.

The outstanding issue is the boom cylinder has some serious cylinder drift constantly. I will have to try bleeding it again.
View attachment 123938
I dug out 7 small cherry trees where we are planning to build a new house and re planted them in a fraction of the time it would have taken with my shovel!
View attachment 123938
View attachment 123939
View attachment 123940
View attachment 123941
Here is to more digging!
Nice update!
Thank you!
 
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mini-mayhem

Member

Equipment
L4200 w/ LA680 , KMS180
Dec 20, 2023
35
11
8
Latvia
I have had a few months of use of the backhoe now. A couple of issues have arisen in that time.
1 leg cylinder is leaking, this has gotten worse over time and is now off the backhoe waiting to go to the hydraulic shop.

The bigger issue by far is the boom dropping under its own weight, this problem too has worsened over time ( or as the weather has warmed up). This has got to the point now it will drop before I can get back in the cab to drive.

Today I have been trouble shooting the cylinder.
First thing I tried way keeping the control pulled back to keep the boom up, this worked with the pump running, but without the pump it dropped.

Now I have disconnecte the cylinder from the boom at one end so I can try bleeding it by using the full travel a couple of times.

On the extension I noticed that the piston rod has droplets on it , I wiped the cyclinder down and sure enough on the next extension there were more droplets
you can see them in this photo
1719390082241.png


While doing this i noticed that when the rod is full retracted it seems to rebound a little on its own as I let go of the controls. about 10mm (3/8").
I tried the drastic action of opening the lines and letting fluid through to see if any trapped air might be released, but this didnt improve the situation.

Video of cylinder rebound when retracted

And lastly
Does anyone know what this 'valve' could be?
1719390743910.png