M5700 Hydraulics

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
I have an old m5700 that has worked pretty well other than some minor bugs until recently. I was mowing the orchard with the 5 foot flail mower and all was going well until the steering got REALLY jerky and then the 3 point was jumpy and definitely reacted to the steering jumping at the same time. I was able to finish most of the work for the day but then today 3 days later after letting it sit as I know it can get "air" in Hydro fluid I tried to do some touch up work mowing and the steering was jerky immediately or "still" depending on how you want to look at it and the PTO for the mower would just stop on even some light grassy weeds and then start back up again then stop, so on and so on. I am waiting for the second of the hydraulic filters to do a full service but the last one was about 100 hrs ago so seems like it shouldnt be that bad already? IDEAS????
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
5,207
1,893
113
Mid, South, USA
Possible suction side leak, or possible filter plugging. You might loosen one of the filters and catch what comes out to see what's in it. Is it milky? Debris? Jelly?
 
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AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
I'll check the suction side for leaks but the oil is clear and clean maybe just a tiny bit of haze on the stick but nothing if you wipe it on your finger? It didn't make sense that the PTO would stop that easy though? Isn't that gear driven when engaged?
 

Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,235
1,018
113
Williamstown Ontario Canada
Please note that your system has a dual or tandem pump. This is two pumps in one body.

Both pumps share a common suction line. The fact that two systems on your tractor are acting up emphasizes the advice from Lugbolt.

The power steering will be one of the pumps and the 3 pt hitch the other.

forum M5700 suction line.jpg


Forum M5700 hydraulics.jpg


You cannot see a suction leak. Replacing all O rings, #80 & #50 plus checking metal pipe for cracks or physical damage would be wise.

Dave
 
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AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
Please note that your system has a dual or tandem pump. This is two pumps in one body.

Both pumps share a common suction line. The fact that two systems on your tractor are acting up emphasizes the advice from Lugbolt.

The power steering will be one of the pumps and the 3 pt hitch the other.

View attachment 62313

View attachment 62314

You cannot see a suction leak. Replacing all O rings, #80 & #50 plus checking metal pipe for cracks or physical damage would be wise.

Dave
 

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
I am going to get the 2nd filter for the Hydro system today and will inquire about the o rings for these suction connections and go ahead and change them as well. What is the connection system on the pipe there where the tandem 050 rings are in the line? I see no "connector" there to disassemble and replace is it a press fit?
 

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
Thank you both for your help I will be getting all of these parts hopefully today and update the results. If it works I'll be back on here late as I'll be mowing again but if not I'll be back with another step? LMAO
 

ruger1980

Active member

Equipment
L4310 w/La682, L225
Oct 25, 2020
395
145
43
CNY
When you reassemble everything remove plug, reference #75 and try blowing air into the transmission housing through the fill port to try and charge the suction line. It will probably be easier with 2 people so you can reinstall the plug when oil comes out of it.
 
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AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
When you reassemble everything remove plug, reference #75 and try blowing air into the transmission housing through the fill port to try and charge the suction line. It will probably be easier with 2 people so you can reinstall the plug when oil comes out of it.
 

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
Good tip. I dont have 2 people or air really out there but I'll try to figure out how to "charge" the line prior to start up. Thanks
 

ruger1980

Active member

Equipment
L4310 w/La682, L225
Oct 25, 2020
395
145
43
CNY
Good tip. I dont have 2 people or air really out there but I'll try to figure out how to "charge" the line prior to start up. Thanks
You can always try plugging the vent and pouring some oil down the suction line before attaching t to the pump. That should help a little as the level of oil in the suction tube will hopefully be higher than the transmission oil level.
 
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Dave_eng

Well-known member
Lifetime Member

Equipment
M7040, Nuffield 465
Oct 6, 2012
5,235
1,018
113
Williamstown Ontario Canada
People have had great luck using a shop vac blowing into the transmission fill plug in order to get fluid flowing into the pump;.

Some air will escape thru the vent but that is OK

Dave
 

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
Ok so after a 3 hour round trip to get the right/wrong parts (filters and a generic set of o rings) fresh Hydro oil and a little flushing/run fresh out the bottom drain plug, the orange terror is back at it with no issues so far. IDK if this is normal but i tried pouring some oil down the suction and that didn't seem to help. Tried cranking with the shut off pulled and the vent open, that didn't work. But mine has an actual universal fitting connector on the Hydro line going to the back, (I assume to the controls) that I was able to crack open and get the flow started. All good now mows like a champ again and chews up the 2 inch branches no problem, steers great, and the 3 point is smooth although a little slow so I'll play with the adjustment under the seat when I get more time.
I did have an inclination to tackle the wiring at some point and get the lights working as none of them currently work and the wires are torn out of most of them. Also if anyone has an idea how to get the temp gauge working that would probably be a good idea as well. Wiring diagram?
 

AVierra

New member

Equipment
M5700, Flail mower, rotary mower, rake, blade, orchard sprayer
Jun 28, 2021
12
2
3
Sacramento CA
Ok so after thinking on this I thought it might help so I wanted to add this info. I have a generic o ring kit from harbor freight that I used the 24.7 ID 31.7 OD o rings for the pump connections and the 24.4 ID 30.6 OD o rings for the suction tube connections and they are working fine. IDK how many models have this (I think terrible) system but the o rings are a pain to get as my dealers all do not stock them so these generics work just fine for minimal trouble.