1992 LX555 Loss of Propulsion

Help Support SkidSteer Forum:

mllud

Well-known member
Joined
Jun 29, 2007
Messages
635
I just got the repair manual that covers the hydrostatic system and steering system. In trouble shooting for/ When one side moves and the other side does not.
Relief valve stuck open; check and repair
Internal pump or motor damage: Check pump/case drain flow.
Brake engaged on one side: Check parking brake system and repair.
Gearbox Damage: Check and Repair.
Broken drive chain: Check and repair.
Linkage Loose or Broken: Check and repair.
New holland brakes their repair manual into several books. This one cost 31$ and 11$ Fed Ex Shipping. This manual is for my lx865 It has the complete brakdown of the pumps /motorsServos/so on and so on. it also gives good discriptions of what to look for when you disasemble and reasemble.The information is very complete of the whole system. Im not trying to sell you on ordering a manual but if you intend to keep your loader Invest in one.The phone no. is 1-800-635-4913 They will need your model no. and may need your serial no. Mike
I read back to one of your earlier post. you said the pump sounds like it was trying to work. Could something else be locked up. maybe the left side gearbox or a wheel bearing. I dont know why a break would lock on one side but the manual sugests checking it. ?? Mike
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
I read back to one of your earlier post. you said the pump sounds like it was trying to work. Could something else be locked up. maybe the left side gearbox or a wheel bearing. I dont know why a break would lock on one side but the manual sugests checking it. ?? Mike
I can assure you that it is not the brake so we can rule that out. I swapped the relief valves right to left and the problem stayed with the left side so I can't see it being that. The unit will move and if you are patient, it will grab and you will propulsion on both sides for a quick spirt so I don't think it is a wheel bearing. I shoud hear back today on the drive motor. I am thinking that if it is not the drive motor that perhaps I have a plugged line running to the left side. Just my luck that I tear the thing apart and found out that all I had to do was to replace a hose. I will keep you posted.
 

Tazza

Moderator
Staff member
Joined
Dec 7, 2004
Messages
16,840
I can assure you that it is not the brake so we can rule that out. I swapped the relief valves right to left and the problem stayed with the left side so I can't see it being that. The unit will move and if you are patient, it will grab and you will propulsion on both sides for a quick spirt so I don't think it is a wheel bearing. I shoud hear back today on the drive motor. I am thinking that if it is not the drive motor that perhaps I have a plugged line running to the left side. Just my luck that I tear the thing apart and found out that all I had to do was to replace a hose. I will keep you posted.
I really doubt its a hose. It sounds more like the motor with the way you describe it.
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
I really doubt its a hose. It sounds more like the motor with the way you describe it.
Well I am being told that it is not the drive motor either. So, the problem is not the pump. not the drive motor, not the chain or sprocket. I will start putting everything back together and checking the hoses. If I can not find anything in the hoses then I guess I have no choice but to take it to the dealer for repair.
 

mllud

Well-known member
Joined
Jun 29, 2007
Messages
635
Well I am being told that it is not the drive motor either. So, the problem is not the pump. not the drive motor, not the chain or sprocket. I will start putting everything back together and checking the hoses. If I can not find anything in the hoses then I guess I have no choice but to take it to the dealer for repair.
Gear box between the Hydraulic motor and the sprockets ? Can you turn the wheels freely with the hydraulic motor out? This may have already been covered earlier. A sheared key will catch somtimes like you described earlier. Just some thougts. Mike
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
Gear box between the Hydraulic motor and the sprockets ? Can you turn the wheels freely with the hydraulic motor out? This may have already been covered earlier. A sheared key will catch somtimes like you described earlier. Just some thougts. Mike
With the drive motor out the wheels do spin freely. However, since I have the motor out, how would access where this shear pin is located at just to make sure. Another thought, if the pin sheared, would I lose propulsion in both directions or just one way?
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
With the drive motor out the wheels do spin freely. However, since I have the motor out, how would access where this shear pin is located at just to make sure. Another thought, if the pin sheared, would I lose propulsion in both directions or just one way?
You should lose drive in both directions. However a break of this sort can have rough edges and hold (bind or jamb up ) in one direction but not in the other for a short period of time b4 it strips completely out.
Does the Hyd shop that worked on the pump and motor have a flow tester? You need to get one and hook the wheel motor hoses too it. See what pressure and flow the motor is cabable of. At full steering lever stoke the pump should put out say 25 gallons per minute (gpm) then the restrictor on the flow meter is screwed in and the pumps ability to produce flow is measured, as the pressure rises the flow meter lets you see if the pressure is dropping or not. If it drops off more then say 10% then the pump is not doing its job. if it maintains 90% of its flow at high pressure then it mus be the wheel motor that is letting the oil slip through.
It would also be a good time to hook it into the RH pump and compare the sides.
If you have pressure and flow from the pumps then the problem must be in the wheel motor or the mechanical linkage from the motor to the wheel. That is all there is to the system
Ken
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
You should lose drive in both directions. However a break of this sort can have rough edges and hold (bind or jamb up ) in one direction but not in the other for a short period of time b4 it strips completely out.
Does the Hyd shop that worked on the pump and motor have a flow tester? You need to get one and hook the wheel motor hoses too it. See what pressure and flow the motor is cabable of. At full steering lever stoke the pump should put out say 25 gallons per minute (gpm) then the restrictor on the flow meter is screwed in and the pumps ability to produce flow is measured, as the pressure rises the flow meter lets you see if the pressure is dropping or not. If it drops off more then say 10% then the pump is not doing its job. if it maintains 90% of its flow at high pressure then it mus be the wheel motor that is letting the oil slip through.
It would also be a good time to hook it into the RH pump and compare the sides.
If you have pressure and flow from the pumps then the problem must be in the wheel motor or the mechanical linkage from the motor to the wheel. That is all there is to the system
Ken
https://webparts.pvassociates.net/cnh/main.php
Sorry but I can not attach pics. Here is the drawing for the drive motor. Which P/N is the shear pin?
 

mllud

Well-known member
Joined
Jun 29, 2007
Messages
635
https://webparts.pvassociates.net/cnh/main.php
Sorry but I can not attach pics. Here is the drawing for the drive motor. Which P/N is the shear pin?
I went to new Hollands parts diagrams to look at the Final drive. I see several keys on shafts where gears and sprockets mount. Thats what I was refering to that may be sheared or broke. I dont think there is a Shear key/pin that is made to shear like you have on some equipment. The ones that are made to shear as a safety when something is over loaded. If your Hydraulic motor and your hydrostatic motor check out ok It has to be between the hydraulic motor and the wheels.
A sheared key may appear ok turning the wheels over by hand. It may only slip under load.
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
I went to new Hollands parts diagrams to look at the Final drive. I see several keys on shafts where gears and sprockets mount. Thats what I was refering to that may be sheared or broke. I dont think there is a Shear key/pin that is made to shear like you have on some equipment. The ones that are made to shear as a safety when something is over loaded. If your Hydraulic motor and your hydrostatic motor check out ok It has to be between the hydraulic motor and the wheels.
A sheared key may appear ok turning the wheels over by hand. It may only slip under load.
I pulled the cover and looked at the chain case. Everything appears to be fine and is free spinning. The chain is tight and is moving as it should. With that said, could it still be something in the chain case? If anything sheared I would have thought the chain would not be moving as it should.
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
I pulled the cover and looked at the chain case. Everything appears to be fine and is free spinning. The chain is tight and is moving as it should. With that said, could it still be something in the chain case? If anything sheared I would have thought the chain would not be moving as it should.
Put the machine up against a pile of dirt and try to spin the tires while observing the chain ccase to see what is turning and what is not.
ken
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
Put the machine up against a pile of dirt and try to spin the tires while observing the chain ccase to see what is turning and what is not.
ken
The unit is torn down with the pump and drove motor out. The wheels will not spin when under load.....that is the whole problem. Even with the pump and motor in place and wheels off of the ground the wheels still do not drive.
 

skidsteer.ca

Well-known member
Joined
Jan 20, 2006
Messages
3,853
The unit is torn down with the pump and drove motor out. The wheels will not spin when under load.....that is the whole problem. Even with the pump and motor in place and wheels off of the ground the wheels still do not drive.
Ok then can you get some sort of tool in place of the motor to turn the final drives? chain the wheel still and see if you can slip anthing in the final drive. I the wheel won't turn when its off the ground the drive must be badly stripped and should slip vary easy.
Either that or you pump/motor is not functioning. A pressure guage T'd into the main hose from pump to motor will tell you if they are putting out a reasonable effort when traveling in one direction.
Ken
 

mllud

Well-known member
Joined
Jun 29, 2007
Messages
635
Ok then can you get some sort of tool in place of the motor to turn the final drives? chain the wheel still and see if you can slip anthing in the final drive. I the wheel won't turn when its off the ground the drive must be badly stripped and should slip vary easy.
Either that or you pump/motor is not functioning. A pressure guage T'd into the main hose from pump to motor will tell you if they are putting out a reasonable effort when traveling in one direction.
Ken
When I worked as a printer and a drive line locked up we started at one end and started wiggling shafts back and forth. There is usually a little play in both directions. Just try to follow it thru the drive line until you find what wont move at all.
There are needle bearings in that gear reduction gearbox. I think those gearboxes get overlooked . Mine uses 90wt gear oil. they dont all get lubed from the chain case. Mike
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
When I worked as a printer and a drive line locked up we started at one end and started wiggling shafts back and forth. There is usually a little play in both directions. Just try to follow it thru the drive line until you find what wont move at all.
There are needle bearings in that gear reduction gearbox. I think those gearboxes get overlooked . Mine uses 90wt gear oil. they dont all get lubed from the chain case. Mike
I don't believe that there is a true gearbox design on this unit. The drive motor shaft end is splined or geared that drives the main sprocket. This sprocket drives another smaller sprocket with the chain attached. Also remember that this area serves as the only hydraulic reservoir that there is. The T idea is what I should have done to begin with but the pump and motor have checked out fine. This is what leads me to belive that I perhaps have a line that is clogged.
 

mllud

Well-known member
Joined
Jun 29, 2007
Messages
635
I don't believe that there is a true gearbox design on this unit. The drive motor shaft end is splined or geared that drives the main sprocket. This sprocket drives another smaller sprocket with the chain attached. Also remember that this area serves as the only hydraulic reservoir that there is. The T idea is what I should have done to begin with but the pump and motor have checked out fine. This is what leads me to belive that I perhaps have a line that is clogged.
It would be good to take the line all off one at a time to make sure their clear.Then you will know theyre clear.and hopfully find a clog. I did forget that this was a unit that shared the chain case. You will find the problem. Never let the machine win. Mike
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
It would be good to take the line all off one at a time to make sure their clear.Then you will know theyre clear.and hopfully find a clog. I did forget that this was a unit that shared the chain case. You will find the problem. Never let the machine win. Mike
No worries....I wil win. I may be slow...but I will win.
 
OP
OP
9

92LX555

Well-known member
Joined
Mar 24, 2008
Messages
83
Thats the sort of enthusiasm we wan to see around here!!! Don't let it beat you.
UPDATE: So now I have the unit at a local repair shop. The same shop that looked at the pump and the drive motor seperately and told me that nothing was wrong. After I got the units back, I put the thing back together in order to move it from behind the barn to around front where the guy could pick it up....it still drives on one side. He has had it about two weeks and he calls me over the weekend and tells me that he thinks it is the drive motor. He tells me that he is driving it out to a repair shop that works on hydraulic pumps and motors (the same shop that rebuilt the boom pump about 2 years ago for me). He says that they tell him the repair could be anywhere from $600 to $1300. He wants to provide the money up front for the repari. So now my question is am I out of line for calling this guy out? I mean he has already looked at the motor and told me nothing is wrong and I paid him $25 for that. So after getting the drive motor back I waisted my labor to put the motor back in, paid him to come pick the unit up, paid him to again examine the pump and the motor and pull the motor, which I already had pulled once. If he did not have my unit I would just run the drive motor out myslef but he has my machine so my hands are tied?
 

Tazza

Moderator
Staff member
Joined
Dec 7, 2004
Messages
16,840
UPDATE: So now I have the unit at a local repair shop. The same shop that looked at the pump and the drive motor seperately and told me that nothing was wrong. After I got the units back, I put the thing back together in order to move it from behind the barn to around front where the guy could pick it up....it still drives on one side. He has had it about two weeks and he calls me over the weekend and tells me that he thinks it is the drive motor. He tells me that he is driving it out to a repair shop that works on hydraulic pumps and motors (the same shop that rebuilt the boom pump about 2 years ago for me). He says that they tell him the repair could be anywhere from $600 to $1300. He wants to provide the money up front for the repari. So now my question is am I out of line for calling this guy out? I mean he has already looked at the motor and told me nothing is wrong and I paid him $25 for that. So after getting the drive motor back I waisted my labor to put the motor back in, paid him to come pick the unit up, paid him to again examine the pump and the motor and pull the motor, which I already had pulled once. If he did not have my unit I would just run the drive motor out myslef but he has my machine so my hands are tied?
I wouldn't be happy about it either... I'd bet its just seals, a seal kit can't be more than $100. As he has the machine he more or less has you by the uum you know!
What garantee do you have that if you spend that much money that it will be fixed? or will he come back and say the motor is now re-conditioned but the problem is still there, it has to be the pump, how about $2,000 more?
I personally would say give me the motor i want to check it. Take it home, pull it down and check the seals as i bet thats all that is wrong. You can then give it to the repair shop to replace the seals if you don't feel comfortable doing it. Just pull the seals, don't pull the geroler apart, but you can look for scratches and scoring. This way you know you aren't being had with the shop saying the seals were shot, the geroler needed replacing. You at least know whats going on.
In his defence, testing just a motor isn't easy you need to load it down, it was wrong for him to *test* it by just hooking oil pressure to it without a load which he obviously didn't do.
 
Top