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How do I bleed the hydraulic system on a John Deere M653 ZTrak mower?
I changed the hydro fliuld (20 50 motor oil) and filter. The machine worked perfectly before the fluid change. I followed all the instructions in the owner's manual and the machine won't move. It seems the fluid will not bleed down into the wheel motors. Hope this info helps.
when you changed the filter and fluid did you run the machine at full throttle and cycle the handles form forward to reverse
when you change the oil on one of these you never get all the oil out of the wheel motors so not much will have to drain down, the pumps will loose their prime and should pick back up
also make sure you did not open the free wheel valve while servicing Kevin K
I checked the freell wheel valve on both pumps...I loosend and retighten just to be sure. I ran the machine at full throttle as the manual instructs while working the levers forward and backward motion. The machine will not move. The system holds 8 quarts and I was able to refill with about 6 quarts. I'm thinking what you said about the pumps loosing prime...The lveres are spongy as if there is fluid in the wheel motors... the pump drive belt is fine. How can I halp the pums pick up prime or is there a way to bleed close to the pump?
there is no system in place to bleed them , you can loosen the lines that go from the pump to the motor and alow any trapped air out, also , do you fill the filter or just put it on ,I always fill thes from habit so i don't know if that would cause your prolbem , you could loosen the filter andlet it fill if air is trapped in it, , you also may jack up the rear end so there is no load on the wheels and see if the pumps can free spin them to work air out,, Kevin K
I had already loosen the lines at the pump and the filter and there is oil in the system. I did fill the filter before installing it. Last night after getting off line disconnected the line at the oil cooler and it was dry. I am going to try to start the machine and loosen that same line gradually with the machine running to see if any air comes out and it fills with oil.
I just disconnected the line at the cooler and oil came up. I did jack the machine up as you suggested and the wheels turn forward only with hand assist..can't get backward motion on the wheels. I loosed the oil filler cap and cleaned the vent with carb-cleaner. I'm still stuck. Can you help?
if you have low pressure air you can put a rag around the air hose and blow air in the tank as you let the machine run , with the handles forward, must be low pressure 10 to 15 psi, also you may try opening the free wheel bypass on both motors and let the machine run with and work the levers, and see if the air will work out like that, as long as the belt is turning the pumps the oil should pick back up , I will look at the book again ans see if i can offer anything eles
I don't have any type of air but I will open the free wheel valves and run the machine..and work levers.
Air trapped in the system inside the motors or line will be the cause other wise it will be an internal failure, and since all you did is can the oil air is the most likely problem , you will never see the air ,
where line 9 leaves the filter and goes to the pump is the most likely area for air becasue these pumps are gravity feed,,, you may crack the lines at the bottom of the pumps and let some fluid run out and retry
next where the steel lines leave the pump and go to to the wheel motors can be cracked and cycle the handles again, this would normally be under pressure so don't put you hand close to the fittings while working the handles,,
this is not a normal problem I have change the oil in these before and not had this problem,
since there are two pumps and two motors, not likely both sides would be out , the common part between the 2 is the filter , and the reservoir,
if you have oil coming out of line 9 in the picture at the pumps it should pick up .
i nothing else helps then i would remove line 9 on the outlet side of the filter and make sure my oil is getting out of the reservoir to through the filter to the pumps. Kevin K
Just checking it Kevin K
I've tried all sugestions. No luck yet. I wil try again tomorrow
did you get hyd oil all the way to the pump,
Yes...evry connection opened had oil accept the top connection to the cooler. The wheels will turn some with the machine jacked up..I have to spin it by hand sometimes to get it going. Then it looses the prime again
the cooler is on the return side of the pumps so it will not have oil until the unit is running so if the pumps done get oil the the coller will not have oil.
there has to be something going on between the tank and the pumps,, so I would recheck by draining the tank, remove the filter, add oil and make sure it comes out of the filter housing with out the filter, then add the filter and take the line off at the tee on the line number 9 and make sure you have all of you oil flow even if you darin the tank through it and add it back in the tank again , if the filter is right and and no part of the packaging is caught in it, and you have oil to the pumps then it is an internal problem with the pumps , and not much eles you can do but take it to the dealer, I would recheck the filter very close, Kevin K
I will check with john Deere tomorrow and see if there are any bulletins out on this for you
Thanks...I'm going to do this 1st thing in the AM. I'll let you know how it turns out.
I open 9 and worked lever..there is oil there and all other connections. I did not crack the connections at the motors as they are hard to access..I also removed the filter and it was full. There seems to be pressure back to the reservoir ..some fluid came out of the cat..very little. I don't know what else to try.
I did not hear from back for the John deere dealer today I will be in there in the morning and I will see if was able to check bulliteins for me,
Sorry we have not been able to help you yet this is an unsual problem for neither pump to pick up oil ,
Thanks for your persistence..I'm out of tricks to try. I drained the fluid and refilled the sytem hoping if it started from scrtch it would work. Nothing...it still will partially spinn the left wheel with no power and almost nothing on thr right. It seems as if it has more prime when it start off and then looses the little bit of prime that it gains. I'll wait to hear back from you. It can't be both pumps are bad when they worked perfectly the last time I used the machine...about 2 1/2 weeks ago.
I wanted to add it will only turn the wheel slow when the machine is jacked up. Onthe floor it has nothing. Hope you can get an answer tomorrow. Thanks.
I will try I know you are tired and what to cut grass
I Did check with John Deere today and looked all the service bulletins on this unit, none on bleeding system problems,
I also read the latest oil specs and recommended bleeding in the john Deere service manual on your unit
first the oil Plus 50 15w40 this is john Deere's brand oil a little lighter that what the oper manual shows but not enough to make any difference
John Deere says to raise the unit off the floor for all of this procedure
open the free wheel valve on both pumps 1 complete turn
start engine and run a 3/4 throttle
move the steering levers al the way forward and hold for 8 seconds, then hold in the rear direction for 8 seconds,, do this 3 times,,
then close the vavles and do the same thing as before with the valves closed
it goes on to say it may be necessary to repeat this process a few time to work all the are out of the system,
It also says to leave the machine on raised while doing this to keep from putting a load one pumps or motors and causing internal damage before the air is all out
I know this is real close to what you have done, but this is the official out of the book , so give 1 more try.
just checking in to make sure you got going
I had not tried this latest method but I will try it today and let you know how it worked out. I have been busy with business but I do need to get this going. Thanks
I tried thie last method and got the same results...the wheeles will move a bit and with no real power. I can stop the wheels with my hand. Can you find out if that meas that the pumps are damaged or is it still just an air lock? Then I would know if I need to have this done by a dealer. Thanks for your help on this..You did stick with the job!!!
sorry my computer is giving me problems the last 2 days
It would not be likely that both pumps are damaged but possible by now with as much as you have run it , Just changeing the oil would not normally casue damage to the pumps.
lets try this as it can not hurt, remove line 13 from the oil cooler and stick it in a 5 bucket, start and run the unit starting at idle, you can put this hose below the tank level if possible,
all the oil not used by the motors should return back to tank through the cooler , run it a a minitue or 2 and try speeding up the motor a little and moving the levers, this should take any back pressure form the coller off of the pumps.
remember you can try this with the free wheel vlavle open and then close them and see what happens , let me now I should be online now every morning and evening to check up dates
OK I'll try tomorrow. Thanks for hanging in there. If I had damage to the pumps wouldn't I hear noise? They are quiet.
Not really the damage would not bet large torn up parts just deep scaring in the pressure areas of the pump.