Massey Ferguson 50d digger

tomo2390

Hello, I have just aquired a 1983 MF 50d backhoe, it has a problem with the drive, I have changed the transmission oil to the correct grade, and cleaned / changed the filters. All it will do is drive (forward and reverse) very slowly, and it has no power, ie. As soon as there is any resistance, mud, incline etc, is will not move at all. Sometimes there is a sudden lurch in whichever direction you are moving, but that's it.
It has the instant reverse system with two pedals. When I emptied the oil sump there was metal filings, but looking into the box itself it all looked ok.
I would very much appreciated any advice or comments you have, before going down the route of breaking the machine to get at the components ( as I don't have an inside workshop big enough ! )
Thank you.

emaherx

You know there are 2 separate oil reservoirs in these? One is for normal gearbox and is filled with universal tractor oil. The other is for instant reverse and is filled with ATF. Filler for ATF is beside pedals. Filler for Universal is beside gear stick.

Edit: Info above is correct for earlier models like 50b. I know later models like 50hx use a single reservoir with universal oil. But it would certainly worth having a look

tomo2390

emaherx wrote: »

You know there are 2 separate oil reservoirs in these? One is for normal gearbox and is filled with universal tractor oil. The other is for instant reverse and is filled with ATF. Filler for ATF is beside pedals. Filler for Universal is beside gear stick.

Edit: Info above is correct for earlier models like 50b. I know later models like 50hx use a single reservoir with universal oil. But it would certainly worth having a look

Thanks for the information, there appears to be only one on my model, and has a dipstick alongside. I will double check in case I missed anything.

9935452

tomo2390 wrote: »

Hello, I have just aquired a 1983 MF 50d backhoe, it has a problem with the drive, I have changed the transmission oil to the correct grade, and cleaned / changed the filters. All it will do is drive (forward and reverse) very slowly, and it has no power, ie. As soon as there is any resistance, mud, incline etc, is will not move at all. Sometimes there is a sudden lurch in whichever direction you are moving, but that's it.
It has the instant reverse system with two pedals. When I emptied the oil sump there was metal filings, but looking into the box itself it all looked ok.
I would very much appreciated any advice or comments you have, before going down the route of breaking the machine to get at the components ( as I don't have an inside workshop big enough ! )
Thank you.

Could the brakes be stuck on. The Mechanisn for the handbrakes on the HX's is known to stick at the slave cylinder.
Is there enough oil in it. My HX if it is low on oil and at an a slight angle will lose drive.
Does ot have any go in 1st gear or is it the exact same in all gears.
When you are in 1st and rev the engine does the engine rev out or is it under pressure/load .
My advice would be to ring Crowleys in cork and they might be able to put you on the right route. They are very helpful lads.

tomo2390

9935452 wrote: »

Could the brakes be stuck on. The Mechanisn for the handbrakes on the HX's is known to stick at the slave cylinder.
Is there enough oil in it. My HX if it is low on oil and at an a slight angle will lose drive.
Does ot have any go in 1st gear or is it the exact same in all gears.
When you are in 1st and rev the engine does the engine rev out or is it under pressure/load .
My advice would be to ring Crowleys in cork and they might be able to put you on the right route. They are very helpful lads.

Hello, I have checked the brakes, all free there. The oil is new and also topped up after running, so happy that's ok. It does seem to be very slightly better in first, and doesn't want to go at all in top gear. It has to be at full revs to move. The oil is ATF . Is the HI the same as the Denton model ?
Thanks again.

Thelostcountry

Torque converter knackered ??

9935452

tomo2390 wrote: »

Hello, I have checked the brakes, all free there. The oil is new and also topped up after running, so happy that's ok. It does seem to be very slightly better in first, and doesn't want to go at all in top gear. It has to be at full revs to move. The oil is ATF . Is the HI the same as the Denton model ?
Thanks again.

Is she reversing perfect in all gears?
If she is id check the linkages for the forward pedal, make sure its engaging fully, ie no excessive wear on pins not letting it engage.
If she is reversing right and not going forward it could be the torque converter. As most of the work is going forward they wear that way the most but reverse could be perfect

emaherx

Universal Tractor oil is filled through filler plug marked 31 on Diagram 1


ATF is filled from the side of transmission case through filler marked 5 on diagram 2

Nekarsulm

If it's equally bad in forward and reverse, it could be your oil pump. Item 13 on the diagram above.
Also there is a very fine mesh filter that may be clogged, item 24 on the diagram.

If reverse is good in all gears but forward is poor, you've probably looking at a burned out forward clutch pack.(not shown on diagram)

These boxes were built by Funk, and are usually very very reliable.

tomo2390

9935452 wrote: »

Is she reversing perfect in all gears?
If she is id check the linkages for the forward pedal, make sure its engaging fully, ie no excessive wear on pins not letting it engage.
If she is reversing right and not going forward it could be the torque converter. As most of the work is going forward they wear that way the most but reverse could be perfect

It seems to be equally poor in both directions, but has considerably less power (almost nothing ) in the higher gears . Thanks

tomo2390

Nekarsulm wrote: »

If it's equally bad in forward and reverse, it could be your oil pump. Item 13 on the diagram above.
Also there is a very fine mesh filter that may be clogged, item 24 on the diagram.

If reverse is good in all gears but forward is poor, you've probably looking at a burned out forward clutch pack.(not shown on diagram)

These boxes were built by Funk, and are usually very very reliable.

I have cleaned the filter mesh, but this had metal filings clogging it, and some in the bottom of the sump.
It will drive at about 3kms but only on the flat with no resistance.
I will take another look at the linkages, also it seems to be stuck in 4 wheel drive, and the selection cable is solid so that will need to be changed. My machine has the filler at the top, but I also saw that it has the filler on the side too, this is marked "oil level", I opened this and ATF flowed from it, nice and clean, so I assume the new fluid in put in from the top. Thanks again

Nekarsulm

That side plug is the level the ATF should be at.
Oil pump putting up no pressure, or perhaps the drive to it is worn away.
Sounds like a splitting job either way.

tomo2390

Thank you for all the above replies, I will take them on board this weekend, and see. Maybe a split job, then have a better idea.

dthubley

Hello did you ever get the mf 50 fixed? was it the pump or converter

thanks Doug

DavidBraga

Can any one tell me what can be this problem?

Best regars

David