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cmcfalls
05-15-2006, 12:39 PM
Wanted to know if any one has any ideas on how to fix hydro problems. Have a lesco walk behind and sometimes the hydro will work, sometimes it wont. All the lines seem fine, no leaks and cant see where any air is being sucked in to the system. Any trouble shooting advice would be great

thanks chuck
C&M Landscaping

geogunn
05-15-2006, 01:16 PM
1) have you checked the hydro tank for fluid?

2) have you checked the hydro by pass valves for closure?

3) is this mower new to you?

GEO :confused:

DynaMow
05-15-2006, 01:35 PM
what do you mean sometimes they do not work? Is fluid pumping? or just no ground speed?

cmcfalls
05-15-2006, 06:31 PM
fluid is full even changed fluid and filter, valves closed, what i mean is sometimes you can mow a yard then all the sudden on another yard the wheels stop turning and you have to tow it back onto the trailer, cant figure this one out

DynaMow
05-15-2006, 06:36 PM
this is just a guess. There is debris of some sort in system and gets moving around and eventually clogs system. Maybe flush system and see from there.

Jcs Lawn and Landscape
05-15-2006, 06:38 PM
i have the same problem with my lesco ztr it is also brand new... the only way it will get working again is if you push it so the wheel turns then it starts to respond again i gotta get this thing fixed

PGA
05-15-2006, 07:00 PM
It could be a bad pump. Take it in to Lesco and have them take a look at it. I had a mower that used to do it and the pump was shot on it.

ed2hess
05-15-2006, 07:10 PM
I guess you jacked it up and ran it to get the air out after changing the fluid and you filled the filter before you put it on. Check the belt tension on the pumps and oil the linkage for forward/reverse.

Dashunde
05-15-2006, 07:30 PM
Does your wb have two seperate pumps and motors?

cmcfalls
05-15-2006, 07:41 PM
filled filter, jacked and ran for 30 min and if i do this again it will run fine for a lawn then crap out again, i will try to flush system with something, i thought pump was bad also but cant understand why it will work fine on one lawn then tow it out of another. i will also replace o rings this time when i flush it. what can you flush pumps with so you dont mess them up

cmcfalls
05-15-2006, 07:42 PM
it has two pumps belt is tight

DynaMow
05-15-2006, 09:28 PM
on my lesco I have to often adjust hydro belt tension. When I was told to try this when mine was having problems, I thought no way. Give it a shot.

ed2hess
05-15-2006, 09:52 PM
it has two pumps belt is tight
I never thought about this much before but one filter and two pumps ...so is both drive motors failing? I wonder how to tell if air is getting into the system? It won't seem like both pumps would fail at the same time unless air is getting into the system? I thought the two systems were isolated but with one filter they can't be?

xi_bowhunter
05-15-2006, 10:26 PM
I have an older lesco walk behind and it does about the same thing. It will go along just fine then it will slow almost to a stop. If I put into reverse then it will sometimes take off again. It will slow and if I just let it work itself out then takes off again.

cmcfalls
05-15-2006, 11:07 PM
I just cant find out where air is coming into system, I guess all new lines would be where to start, I have to many lawns in which I need a wb maybe a new one is the way to go. no more lesco for me too many problems

cmcfalls
05-15-2006, 11:10 PM
both give out, both pumps work independant but together

Dashunde
05-16-2006, 08:17 PM
both give out, both pumps work independant but together

Explain further...
Does each pump separately drive its own motor using a common fluid tank and filter?

Does your control linkage for each side lead directly to each pump?
Or does it have some other type of setup?

What are common shared parts in the drive system?
Filter
Fluid
Reservoir
What else?

Does one pump quit before the other? If so, does that side always quit first?

What has to happen before it will start working again?

cmcfalls
05-16-2006, 08:38 PM
one belt turns both pumps, both share same fluid, tank res, filter, link control their own pump, each pump controls own motor, one side stops before other does usually but not always

Turf Technologies
05-16-2006, 09:11 PM
I have an older lesco walk behind and it does about the same thing. It will go along just fine then it will slow almost to a stop. If I put into reverse then it will sometimes take off again. It will slow and if I just let it work itself out then takes off again.


Your hydro pulley needs adjusted.

Evergreenpros
05-16-2006, 10:09 PM
Did you put the correct type of fluid in the system? Sounds like when it gets hot it craps out? I know I was surprised when it called for 10w-30 instead of hydro fluid in mine.

I put Mobil synthetic in mine and have no problems. My bet would be plugged/wrong flow filter or wrong fluid type. Air doesn't get into hydro systems. They run at such high pressure if there as a leak to get air into the system it would be spraying out fluid like a firehose. On the hydro tank side there is no pressure, the pumps just draw fluid from there then pressurize it and send it to the wheel motors.

Envy Lawn Service
05-16-2006, 11:06 PM
OK... this can be a lot of things.

So my question is....
Was it doing this prior to changing the fluid and filter?


If so, it shouldn't have anything to do with being the wrong fluid or wrong filter.

So my guess would also be the hydro drive belt, especially since it is crapping out on both sides at the same time. Even more so if it does it going up hill or anything like that.

cmcfalls
05-17-2006, 08:06 AM
did this before filter change, thought might be problem, tightened belt but will retry again and see what happens and report back

Dashunde
05-17-2006, 06:33 PM
I wondering... and I didnt see it mentioned...

Did you RE-fill the tank after you refilled the system?
I mean, you filled the tank to start with, ran, purged, (or whatever is required) for both sides.... but then, did you top off the tank?
If not, that is where it could be sucking air in - especially on hills.

I'd still like to know what makes it start working again? Cooling off?

Be sure that the oil your using is not foaming up... ?

cmcfalls
05-17-2006, 07:56 PM
sometimes working the levers back and forth makes it go again, sometimes sitting over night will start to work, other times i have to jack it up and let it run for 30 minutes to get it going again. different each time , tank is full

Envy Lawn Service
05-17-2006, 09:49 PM
sometimes working the levers back and forth makes it go again, sometimes sitting over night will start to work, other times i have to jack it up and let it run for 30 minutes to get it going again. different each time , tank is full

Oh dang then... If it is not the belt then it certainly sounds like you are either having and issue with drawing air in the system or cavitation.

In either even, you are getting pockets of "void" in the fluid.
Eventually these make there way around and collect somewhere, causing the machine to stop.
This is bad and very hard on hydros....
Don't be complaining... say to yourself "wow, I can't believe they have survived".
I say that because you really have been lucky.

The question remains though... is it air or cavitation?

Do you have any visible leaks or weeping anywhere?
Any spewing around the reservior cap?

In my personal experiences, cavitation for some reason has only affected my previous junk mowers in different ways than you are experiencing MOST OF THE TIME. In otherwords, usually it would only effect one side in one direction, or one side, or one direction... rarely both sides in both directions.

So my hunch is air... hopefully. If you have no leaks or weeping anywhere, your low pressure return lines/fittings are suspect. As I understand it, these would suck air into the system during operation rather than leaking fluid out.

You should really open your tank and look inside at the oil while you have it jacked up purging the system. You'll probably see the air bubbles or foaming returning to the tank.

mike lane lawn care
05-17-2006, 11:02 PM
i had a hydro tractor that did this, once the hydro system heated up, the mower would hardly move, the hydro had to replaced.

old dog 80
05-17-2006, 11:02 PM
Sometimes a hydro belt when worn and checked(needs replaced) is glazed and will slip-on any hydro.How old is the belt?

cmcfalls
05-24-2006, 11:04 AM
thanks everyone for your help, I just cant get this figured out, I think a new mower might be all I can do, this lesco only has 700 hrs on it, hate to replace pumps

Dashunde
05-24-2006, 07:27 PM
Ack... I have a hard time buying that both pumps are out at the same time... something else has gone amuck.
Try changing to a completely different fluid - stay with whatever type is recommended, but go with a different brand or synthetic.
Also, contact whoever made your pumps (I doubt Lesco makes their own pumps), ask them directly what you can run in those pumps, do the same for your wheel motors - find a fluid that works in both of them.
The motor oil thing is just... odd. Motor oil is not really meant to be compressed in this way.

Three more things...
Make absolutely certain that you have the right filter on it, call Lesco. It just might have had the wrong filter on it to begin with - did you check on this or just take numbers from the old one and do a direct replace?

When you re-change the fluid, let it run a looooonnnnggg time before trying to use it. Maybe an hour or so to be certain that ALL of the air is out.
Let it free-wheel at a low speed to allow the air to separate out and up.

Double check the lines that feed your pumps from the tank - remember, its a bit of a vacuum there and if its leaking (sucking air) then you may not see a visible fluid leak. Take them off, cap one end of each, find a fitting or two at Home Depot that will allow you to put 20 or 30 psi in them, then check for leaks with soapy water.


Overall, taking into account that it quits when hot, works after some free-wheeling, and everything else you have stated, it really does sound like "frothed" or foamed-up fluid is trying to circulate.

Envy Lawn Service
05-24-2006, 09:31 PM
Yup... probably industry standard pumps and wheel motors.

Yup... probably sucking air from the return lines/fittings.

cmcfalls
05-24-2006, 09:42 PM
will try new filter and fluid, I thought odd motor oil in hydro too, but who am I. maybe I should try hydro fluid? do you think it would hurt???

Envy Lawn Service
05-25-2006, 12:03 AM
Most of these mower hydro systems use motor oil.

I think it's odd too, but don't just go putting hydralic fluid in them.
Use only what is specified in the manual.

I'm guessing these are hydro gear pumps and parker ross wheel motors?

cmcfalls
05-25-2006, 08:39 AM
found service manual for pumps and specs for purging and how to rebuild if need be. Belt is less than a season long. will try new purging specs and see what happens between the rain today

cmcfalls
05-27-2006, 11:51 PM
new purging specs seemed to have worked so far, ran all day no problems, thanks to all for your input, lesco purging specs not enough to release all air

Envy Lawn Service
05-28-2006, 12:09 AM
new purging specs seemed to have worked so far, ran all day no problems, thanks to all for your input, lesco purging specs not enough to release all air

Good to hear that!
Glad you got the air out and glad it didn't do any damage while in there.

But could you please elaborate a little more about the purging proceedures you used?

cmcfalls
05-28-2006, 12:25 AM
had same problem, jack up drive wheels, open valves on pumps so it can free wheel, at slow idle work levers forward to reverse 5 times let run approx 5 minutes, then while still running close off valves to let wheels turn again, work levers again let fun 5 min more, should solve problem make sure oil is full, I have service manual for pumps let me know if this is good, it also tells you how to rebuild which they told me I couldnt do

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Envy Lawn Service
05-28-2006, 12:57 AM
Dang... I just took for granted that you were supplied with the proper purging instructions.

I'm guessing maybe they left out opening the bypass valves or working th controls in a no-load state, or both? That must be done to circulate the fluid and purge air out of the system and into the reservior where it can escape to the top of the oil.

I've been told that air and cavitation are the two most detrimental things to have in the system... even worse than a little dirt, as that will get caught by the filter. I'm glad you didn't suffer any damage.

Dashunde
05-28-2006, 12:16 PM
Glad to hear it worked out.