Main pump problems.

[V8Druid]

I am from Slovenia actually… I don’t know why it says that, I don’t even remember putting in a location when setting up the account.

we used to have a Slovenian on the old CEF - Metod Narobe .. from Ljubljana .. he and I still keep in touch on FB ........ it looks a lovely country too and yeh he tells me things are expensive there - he has bought a lot from the UK in the past and I picked up and shipped a nice little bandsaw out to him a while ago

 

[Taat]

we used to have a Slovenian on the old CEF - Metod Narobe .. from Ljubljana .. he and I still keep in touch on FB ........ it looks a lovely country too and yeh he tells me things are expensive there - he has bought a lot from the UK in the past and I picked up and shipped a nice little bandsaw out to him a while ago

Thats nice to hear. Yeah things are getting pretty rough here now, it’s a shame for such a small country. The guy that I bought this Takeuchi from said then that he had five excavators coming from UK that he is gonna sell ahead here. I really don’t know how that would turn out profitably for him since UK seems to have a higher standard an all the transportation expenses included. I didn’t want to dig into his finances, but I guess it did and he sold them pretty quickly.
Just for reference, when I was rebuilding the slew motor on this machine, just for one piston the Takeuchi dealer quoted me 200€. Which would add up to 1800€ just for the set of nine pistons. I don’t know if that is a lot of money in other countries but here this is almost two monthly paychecks.

But yeah it is beautiful here. It is currently raining constantly. Which I believe is also known for the UK.

 

[V8Druid]

Thats nice to hear. Yeah things are getting pretty rough here now, it’s a shame for such a small country. The guy that I bought this Takeuchi from said then that he had five excavators coming from UK that he is gonna sell ahead here. I really don’t know how that would turn out profitably for him since UK seems to have a higher standard an all the transportation expenses included. I didn’t want to dig into his finances, but I guess it did and he sold them pretty quickly.
Just for reference, when I was rebuilding the slew motor on this machine, just for one piston the Takeuchi dealer quoted me 200€. Which would add up to 1800€ just for the set of nine pistons. I don’t know if that is a lot of money in other countries but here this is almost two monthly paychecks.

But yeah it is beautiful here. It is currently raining constantly. Which I believe is also known for the UK.

Met used to buy all sorts here and ship them back at pretty good rates - usually on return loads

 

[Taat]

Met used to buy all sorts here and ship them back at pretty good rates - usually on return loads

Maybe I should quit farming and CNC industry to become a UK-Slovenia dealer.

 

[Mick-the-fitter]

If its making flow/pressure then could just be a scored valve plate leaking passed, still have to strip them but I would chance it

 

[Taat]

If its making flow/pressure then could just be a scored valve plate leaking passed, still have to strip them but I would chance it

What do you mean by you would chance it?

 

[Taat]

Okay, so I was just working with an excavator and the right track got so weak that I could barely move even on level ground. I went to put on the pressure gauges on the pumps to see how it behaves. Results were like the last time, except now I put the metal bar to the sprockets and engaged the tracks to the fullest. Pressure at both pumps reached the spec of 350bar when running individually. And if running both at the same time the left is up to spec and right is about 220bar. How does that make sense? So the alleged faulty pump has the potential of running to max pressure on certain conditions. Like when pulling the stick and bucket at the same time it also does…

But before testing if I ran just the right track it had no power, but if I do now it feels pretty strong and tracks fairly straight. There was just about twenty minutes in between to put the gauges on and find the metal bars. Except there was lots of pressure in the hydraulic tank that I bled out.

I am completely baffled now.

 

[Mick-the-fitter]

Right so did you all these tests on the original configuration of pump supplied oil. and then do the same tests with the hoses changed from P1 to P2?

 

[Taat]

Right so did you all these tests on the original configuration of pump supplied oil. and then do the same tests with the hoses changed from P1 to P2?

All of the pressure test have been done on the original configuration yes. I will try to do tomorrow with the switched outputs.

 

[doobin]

Just for reference, when I was rebuilding the slew motor on this machine, just for one piston the Takeuchi dealer quoted me 200€. Which would add up to 1800€ just for the set of nine pistons. I don’t know if that is a lot of money in other countries but here this is almost two monthly paychecks.

Bloody hell, if €1800 is two monthly paychecks then what do you pay for a 13t digger and driver for a day?

 

[Taat]

I tried to swap the regulators, nearly impossible since everything is so cramped up on this machine. Couldn’t do it anyway. While I was sure the problem is the pump since I switched the outputs and I had the oil drained out anyway, I have been busy two days taking the pump off and apart (a real pain in the…).
Anyway the valve-port plate on faulty pump is broken on the outlet side. While I found the cause of weak pump, I have no idea what could cause this. Anybody have any idea?
I can upload pictures of other parts if anybody wants to take a look. But they seem okay to me. I will have them checked by the more experienced guy I know.

 

[V8Druid]

I tried to swap the regulators, nearly impossible since everything is so cramped up on this machine. Couldn’t do it anyway. While I was sure the problem is the pump since I switched the outputs and I had the oil drained out anyway, I have been busy two days taking the pump off and apart (a real pain in the…).
Anyway the valve-port plate on faulty pump is broken on the outlet side. While I found the cause of weak pump, I have no idea what could cause this. Anybody have any idea?
I can upload pictures of other parts if anybody wants to take a look. But they seem okay to me. I will have them checked by the more experienced guy I know.

at least you have found something

 

[Mick-the-fitter]

Show me all the other internal parts of that pump

 

[Taat]

There are some scratch patterns on some sliding surfaces but can’t be felt by finger, so the grooves are probably less than 0.01mm deep.
The worst surface to be seen is actually on the good pumps swash plate holder and its counterpart. My guess is about 0.05mm to 0.1mm deep (IMG_3311, IMG_3312).
There are also grooves on the part which pushes to the spring, I don’t know if that is normal, they are also pretty deep, on the good pumps also.

 

[Taat]

The faulty pumps cylinder block and broken valve plate have a surprisingly good surface. I just wanted to try and hand lapped them together by hand for two minutes with a 10ųm diamond solution and its surfaces got a lot better.

 

[Mick-the-fitter]

Ok a wild guess it’s been apart and put back together out of line with the peg to line up with the slot on the valve plate, started doing up bolts and relaxed and put back in the correct place and done back up, damage done!! If it was my pump I wouldn’t risk putting it back together and using it! That broken valve plate is destined to self destruct, I also guess.you would get spare parts for it?

 

[Taat]

Ok a wild guess it’s been apart and put back together out of line with the peg to line up with the slot on the valve plate, started doing up bolts and relaxed and put back in the correct place and done back up, damage done!! If it was my pump I wouldn’t risk putting it back together and using it! That broken valve plate is destined to self destruct, I also guess.you would get spare parts for it?

Oh I don’t mean to reuse it. What about other parts? Do you seen any abnormal wear on them? Pistons have some scratches, as well as the slippers. Can I just lapp the slippers so they are nice and flat?
What about that swash plate holder which sets the angle that is badly scratched? Do I need new part?

Since I have everything apart I was thinking of changing the rotary groups in both pumps (valve plates, cylinder blocks and pistons). Including the bearings and all the seals and O-rings.

 

[Mick-the-fitter]

If you are going to replace those parts anyway that’s good, cleaning or facing parts may help but you are taking away metal that will wear! It could be that at some point the machine has run low on hydraulic oil

 

[Taat]

If you are going to replace those parts anyway that’s good, cleaning or facing parts may help but you are taking away metal that will wear! It could be that at some point the machine has run low on hydraulic oil

I will have the parts checked tonight by a guy I know that rebuilt some pumps before.
I am not 100% sure what parts to reuse, so it’s probably better that way.
What makes you think that the machine was low on hydraulic oil? Because of the broken valve plate, or some scratches on some parts?

 

[Mick-the-fitter]

I will have the parts checked tonight by a guy I know that rebuilt some pumps before.
I am not 100% sure what parts to reuse, so it’s probably better that way.
What makes you think that the machine was low on hydraulic oil? Because of the broken valve plate, or some scratches on some parts?

Good idea to get it all checked, the large amount of scoring and lines would indicate dirty or low oil.