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View Full Version : Exmark hydro probs?


lasher66
08-29-2009, 09:07 PM
HI,
Alright, I blew a hyro pump while cutting the other day. It started making alot of clinging noise inside the pump then started shooting fluid out of the shaft seal where the pulley is mounted. I bought a new parker pump (which is the aftermarket replacement for hydro gear). Anyways put the pump on and changed the filter and fluid. Started mower up and everything worked fine with no leaks for about five minutes. Now the other pump decided to start shooting fluid out of the same spot as the old pump on other side through the shaft seal where the pulley is mounted. Is this just a coincidence. So I guess I will buy another pump and see what happens. Any ideas? Thanks

Jason

Restrorob
08-29-2009, 09:47 PM
Is this just a coincidence


Sounds like you have my kind of luck.... :(


Little advise, Clean/flush the hydro tank-all hoses and both wheel motors well. You don't want any metal shavings from the blown pumps entering the new ones.....


Good Luck

lasher66
08-30-2009, 02:40 PM
Whats the best method to clean wheel motors,hoses,tank ect..
Thanks

Jason

Restrorob
08-30-2009, 05:00 PM
It's a little time consuming and requires a few quarts of oil but is cheaper than replacing components.

Compressed air is most helpful....

Remove the tank and flush with mineral spirits then blow the inside dry.

Remove both wheel motor hoses from the pumps, Hold the hoses over a drain pan and rotate the wheel hub. Wheel motors are in a sense pumps as well so what oil is in them most will be pushed out the hose. Then blow a continuous SMALL amount of air through one hose while slowly rotating the wheel hub until all excess oil is out of the motor.

Now put a quart of oil in a clean container or cut a hole in the top large enough for the hose to fit inside, Rotate the wheel hub and the motor should pull the oil into it and push it out the other hose over the drain pan.

Repeat the blow out while rotating procedure again, Once done swap hoses and repeat the pulling in of new oil procedure turning the wheel hub the opposite direction followed by the blow-out.

Continue the process until you get clean non-contaminated oil through the motors, Once clean pull new oil into the motors (pre-fill) then everything can be re-connected and the system filled and purged of air.

lasher66
08-30-2009, 05:25 PM
thanks for the help

Mrplowcjc
08-30-2009, 09:59 PM
I also have a laser with hydro troubles. I replaced the left hydro pump over the winter on a spare machine. The machine has about 20 hours on the new pump this year and all of a sudden it is very hard to get any motion out of that wheel.. When you jack up the machine the wheel run fine. Any suggestions?

Restrorob
08-30-2009, 10:14 PM
Any suggestions?


Sure, Click HERE (http://www.lawnsite.com/showpost.php?p=1987834&postcount=2)......

lasher66
08-31-2009, 10:20 AM
Does the oil have to be the 15w50 expensive stuff or can I use cheap oil to flush wheel motors out?

Jason

lasher66
09-02-2009, 10:03 PM
Alright, last question hopefully. As stated in first post, after I replaced old pump with new one, thats when my other pump went bad. I am in the process of cleaning all components as you states before I put the second new pump in. Anyways, I did notice metal shavings in reservoir. Now I am wondering if this stuff contaminated my first new pump I put in and is there a way to flush it so it doesnt keep circulating? Thanks for your help again.

Jason

Restrorob
09-03-2009, 12:05 AM
Sorry I missed your post #8, You really don't have to use the high dollar oil for flushing but use the same weight. But, For the final (pre-fill) use the same oil your going to run.


You can flush the new pump in the same manor as the wheel motors (turning the drive pulley by hand). Just install the hoses back on the pump then remove the other end from the wheel motor.

Mrplowcjc
09-03-2009, 09:49 PM
I checked out all the suggestions that you said. I did have a loose fitting and the fluid was getting air in it . I tightened up the fitting and still no better. I jacked up the mower and ran for 1 hr. to get all of the air out of system, when the mower is jacked up the wheel runs fine. When the machine is on the ground I still have no motion out of this wheel. Is this possibly a wheel motor and how can I check wheel motors and pumps to see if they are the problem. Thanks for your help.

Restrorob
09-04-2009, 12:06 AM
I jacked up the mower and ran for 1 hr.


Did you move the joysticks full forward then full reverse slowly at about 3/4 throttle during this hour ?


I've read of guy's swapping wheel motors from side to side for testing, But that's not a advisable way of testing. Metal shavings can be transfered to the working side and cause damage.

The only real test would be on the pump with a flow meter, If the pump passes the test the wheel motor has to be the faulty part. A flow meter runs in the $350 range so not every shop has one, You can call your local shops and see if they have one and what they charge just for the flow test.


Good Luck

Mrplowcjc
09-04-2009, 10:30 PM
I ran the machine with the control lever pinned forward for one half hour and pinned back for one half hour. With the machine jacked up the wheel works fine. When it is on the ground all I get is a little movement forward and a whining noise when you try and go backward. Is there any test for a wheel motor or would I see anything if I took the pump or motor apart. thanks again.

Restrorob
09-04-2009, 11:12 PM
A whining sounds like there may still be air trapped in the system, Just for giggles try bleeding as I posted above. Move the sticks back and forth 10-12 times.

Some hydraulic component rebuilding companies have machines that pumps and wheel motors can be mounted on for testing, I doubt there's a dealer that has a machine such as this in their shop. Most OEM's say to run a flow test on the pump, If it passes replace the wheel motor. If it fails the test replace it and hope the wheel motor is still good.

Unless you found a obvious failure (something broken) inside a wheel motor it could be nearly impossible to see wear/clearance issues relating to loss of power. I don't recall ever seeing a clearance spec sheet on a wheel motor.

Mrplowcjc
09-04-2009, 11:15 PM
Would you keep the machine jacked up or on the ground??

Restrorob
09-04-2009, 11:32 PM
Gotta be jacked up....