# MF35 ( MF205 ind.) hydraulic lift problem



## Joakim (Aug 11, 2018)

My MF35 had problems lifting on three point. Low force.
Removed top cover and hydraulic pump and lift cylinder.
found broken piston rings on 2 pistons.

Renewed serviced pump: new pistons, cylinders with valves, brass bushings, o-rings and presse releif.
Control valve got new slide and o rings.

Lift cylinder was honed and got new piston rings.

After remounting it all 3 point will only reach about 40 Bar and will not lift my weight connected on 3 point.
Pressure measured at the tipp connector.

Stopping tractor confirmes no leak in system after pump check valves. 
The 40 Bar stay present at least 10 min with no running pump.

Looking at the pressure releif no noticeble oil discharge when system is at 40Bar.

Anyone with any ideas why i only get 40 Bar out of my system ??

Thanks for any help.


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## Hoodoo Valley (Nov 14, 2006)

Welcome to the forum Joakim! Sure sounds like you covered everything there imaginable. I'd make a couple suggestions but they'd only be guesses. Sorry I can't be of much help. We do have some experts in this area of expertise and they will be along shortly to help out.


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## Guest (Aug 11, 2018)

You might consider putting your tractor in the Showcase (located under the TRACTOR button at the top of the page). A perk is that if you add your tractor to the Showcase, it becomes instantly eligible to be entered in our monthly tractor contest, in progress right now. Please be sure to add your vote for September's Tractor of the Month, which is found on the main Forum menu as the fourth category, listed as "Tractor of the month". The poll is at the top of the page. Thank you for your vote, and again, welcome to The Tractor Forum!​


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## RC Wells (Dec 26, 2008)

Watch this Youtube: 




Usual cause of low lift pump pressure is worn bores in the pump. I generally use one of HamiltonBobs premium pumps for ten spline drives, less cost and problem than buying the pistons and case and other parts: http://hamiltonbobs.com/cart/search/massey-ferguson-harris-m115/35-mm10?page=1 They are also sold on Amazon for under $200 with free shipping.


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## deerhide (Oct 20, 2016)

Not sure what "bar" is correct.Your tractor may have an internal hydraulic oil filter, that is plugged up. Did you find one when you had it apart?


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## Joakim (Aug 11, 2018)

deerhide said:


> Not sure what "bar" is correct.Your tractor may have an internal hydraulic oil filter, that is plugged up. Did you find one when you had it apart?


Filter was replaced with a fine metal mesh type filter.


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## Joakim (Aug 11, 2018)

RC Wells said:


> Watch this Youtube:
> 
> 
> 
> ...


Thanks .. I looked throgh that video before i starter the rebuild.

As i am Norwegian i bought all the parts from suplier in Norway.
pump repair kit -


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## Joakim (Aug 11, 2018)

deerhide said:


> Not sure what "bar" is correct.Your tractor may have an internal hydraulic oil filter, that is plugged up. Did you find one when you had it apart?


2500 psi = 172 Bar

40 Bar = 600 psi


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## dozer966 (Dec 30, 2014)

honing a cylinder will get rid of light scoring but if cylinder wall is out of round it may bypass even with new packings


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## deerhide (Oct 20, 2016)

Joakim said:


> Filter was replaced with a fine metal mesh type filter.


Is the filter too fine? A slim chance but maybe take that filter out and give the lift a try. You only have to drain enough oil to take the cover off and the pump will still be able to pick it up. Is the standpipe in perfect condition and is it's 'o' ring good or new?
(There is a lot of people with Norwegian ancestry here where I live)


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## Joakim (Aug 11, 2018)

Hi all.. Thanks for all the tips..
Think the problem is solved..

I could not get the problem out of my head so I travelled back to the cabin today ( tractor is used for snow plowing at our cabin in Sweden)..

This is a rare version of MF205 industrial with perkins diesel, converter clutch, Davis front loader and also the MF35 agri back end with PTO and 3 point.

I was tricked by the converter i guess.
Noticed that the PTO shaft also stopped when pump reached 40Bar...

Switching over PTO to ground mode and moving tractor og was lifting with full force.

Guess the momentum for pumping 40 Bar equals the "netural" momentum of the converter.

For my next trip to the cabin I will try what I belive is the solution :

place gear box in netural and push down on converter engage pedal during lifting of 3 point to get the converter output shaft to rotate with full force. 

Any thoughts if I an om the right track?


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## BigT (Sep 15, 2014)

If the converter stops at 40 bar (600 psi), maybe it is the problem?


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