No hydraulics

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tomagregg

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I have lost my hydraulics. The belt turns the pulley and the pulley turns the shaft. I would like to check my hydraulic pump pressure. Does anyone rent a hydraulic tester that will work on an 863? The manual calls for a MEL 10003-hydraulic tester and a MEL 10006 hydraulic test kit I get a HP WARNING LIGHT and then the machine shuts down after 30 seconds. Any ideas what else I could check besides hydraulic pressure?
 

OldMachinist

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Seems like I remember you had the same problem earlier this year. What did you do then to fix it?
 
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tomagregg

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Seems like I remember you had the same problem earlier this year. What did you do then to fix it?
I left for the winter. I just returned and skid steer still sitting in the same spot. I found out the problem, there is no hydraulic fluid. Filled up the reservoir, started it up and it moved a couple feet. Hydraulic warning light came on and machine shutdown. Checked the reservoir again and nothing on the dipstick. Put in another 5 gallons. Machine moved back-and-forth, bucket raised up and down. Hydraulic warning light came on the machine shut off again. Damn, check the dipstick ,no oil ,put in another 4 gallons. Drove around the driveway and everything work, I was elated. Next morning came out and started it up and the hydraulic pressure light came on again. I lifted up the cab and there was a small lake of hydraulic fluid on the filter side of the chassis. I pumped it out and it came to over 4 gallons. So overnight it leaked the whole reservoir out. Spent several hours steam cleaning and Gunking out the muck. Going to town tomorrow to get more hydraulic and some fluorescent dye. Believe the leak is somewhere under the hydrostatic pump where the oil reservoir line comes into it. If that's the case, it looks like it's going to be a real job to fix it.
 

Tazza

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I left for the winter. I just returned and skid steer still sitting in the same spot. I found out the problem, there is no hydraulic fluid. Filled up the reservoir, started it up and it moved a couple feet. Hydraulic warning light came on and machine shutdown. Checked the reservoir again and nothing on the dipstick. Put in another 5 gallons. Machine moved back-and-forth, bucket raised up and down. Hydraulic warning light came on the machine shut off again. Damn, check the dipstick ,no oil ,put in another 4 gallons. Drove around the driveway and everything work, I was elated. Next morning came out and started it up and the hydraulic pressure light came on again. I lifted up the cab and there was a small lake of hydraulic fluid on the filter side of the chassis. I pumped it out and it came to over 4 gallons. So overnight it leaked the whole reservoir out. Spent several hours steam cleaning and Gunking out the muck. Going to town tomorrow to get more hydraulic and some fluorescent dye. Believe the leak is somewhere under the hydrostatic pump where the oil reservoir line comes into it. If that's the case, it looks like it's going to be a real job to fix it.
It shouldn't be dumping tha much oil, has to be a bad hose. Hopefully access isn't bad either. Some are hard, some are not too bad, hopefully it's one of the easier ones.
 
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tomagregg

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It shouldn't be dumping tha much oil, has to be a bad hose. Hopefully access isn't bad either. Some are hard, some are not too bad, hopefully it's one of the easier ones.
I found my leak finally. It's coming out from underneath the rear chain case cover. Something has forced the cover up in the back corner with so much pressure that it snapped a bolt off. The plate is now bent in the corner and raised up about an eighth of an inch. Here's where things get weird. When I add hydraulic fluid to my plastic hydraulic reservoir tank it comes out from underneath the plate. I was under the impression that the chain case was a totally different system from the hydraulic system. Why would fluid from my hydraulic tank becoming out of my chain case? What could have caused my cover to get bent like that? Does anybody have an idea what's going on?
 

OldMachinist

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I found my leak finally. It's coming out from underneath the rear chain case cover. Something has forced the cover up in the back corner with so much pressure that it snapped a bolt off. The plate is now bent in the corner and raised up about an eighth of an inch. Here's where things get weird. When I add hydraulic fluid to my plastic hydraulic reservoir tank it comes out from underneath the plate. I was under the impression that the chain case was a totally different system from the hydraulic system. Why would fluid from my hydraulic tank becoming out of my chain case? What could have caused my cover to get bent like that? Does anybody have an idea what's going on?
Yes the chaincase and the hydrostatic/hydraulic systems are separate systems but if you have a failure in one or both of the hydrostatic motor carriers seals then fluid will be forced into the chaincase. It sounds like you've had a major failure in a motor to have that much oil leaking into the chaincase to build up enough pressure to force the cover open.
I've seen a cover get forced open before when enough water leaked in and froze.
 

antfarmer2

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Yes the chaincase and the hydrostatic/hydraulic systems are separate systems but if you have a failure in one or both of the hydrostatic motor carriers seals then fluid will be forced into the chaincase. It sounds like you've had a major failure in a motor to have that much oil leaking into the chaincase to build up enough pressure to force the cover open.
I've seen a cover get forced open before when enough water leaked in and froze.
If it drives ok might just be the seal from the drive motor to the chaincase did mine for $16 bucks a side and about a hour on each on my 743
 

antfarmer2

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If it drives ok might just be the seal from the drive motor to the chaincase did mine for $16 bucks a side and about a hour on each on my 743
And built the tool to set it out of threaded pvc coupler and a square plug cheap and worked great
 
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tomagregg

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And built the tool to set it out of threaded pvc coupler and a square plug cheap and worked great
When I drained my chain case I had almost 25 gallons come out. After I got the cover off I checked the case with some florescence dye and I found the leak coming out of one of the motor seals. It appears the rear chain case cover had been bent by a previous chain failure from a previous owner. He had just gooped it up with RTV sealant. It also bent the frame underneath the cover. What would be the best way to straighten out the ding in the frame? It is in the rear corner right above the large rear sprocket. I can straighten out the cover with no problem. How hard is it to replace the motor seals?
 

antfarmer2

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When I drained my chain case I had almost 25 gallons come out. After I got the cover off I checked the case with some florescence dye and I found the leak coming out of one of the motor seals. It appears the rear chain case cover had been bent by a previous chain failure from a previous owner. He had just gooped it up with RTV sealant. It also bent the frame underneath the cover. What would be the best way to straighten out the ding in the frame? It is in the rear corner right above the large rear sprocket. I can straighten out the cover with no problem. How hard is it to replace the motor seals?
Change both sides mine were easy can't see yours from here just have to pull the drive motors get the seal out and replace.........a bit of heat and a hammer to bend it back or a porta-power if no swing room
 
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tomagregg

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Change both sides mine were easy can't see yours from here just have to pull the drive motors get the seal out and replace.........a bit of heat and a hammer to bend it back or a porta-power if no swing room
Thanks. Can you tell me what size bolthead ( the 4) that hold the hydraulic motors on? It looks like a big torx. I had a 20 and that was too small. I tried a 5/8 and 11/16 12 point but they wouldn't fit.
 
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tomagregg

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Thanks. Can you tell me what size bolthead ( the 4) that hold the hydraulic motors on? It looks like a big torx. I had a 20 and that was too small. I tried a 5/8 and 11/16 12 point but they wouldn't fit.
I got it. I cleaned off the head real good and a 5/8 12 point socket fit on it.
 

antfarmer2

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Thanks. Can you tell me what size bolthead ( the 4) that hold the hydraulic motors on? It looks like a big torx. I had a 20 and that was too small. I tried a 5/8 and 11/16 12 point but they wouldn't fit.
No sorry sound like trip to harbour frieght use the right one don't want to mess them up to remove the seals I drilled two holes in the seal don't go to far!!!! then put two wood screws in a strip of wood lined up then put a small block of wood in the center and tightend the screws and it will pop right out on mine there was a big washer behind the seal with a quad ring behind that it was gone so good time to replace it if yours needs it
 
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tomagregg

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No sorry sound like trip to harbour frieght use the right one don't want to mess them up to remove the seals I drilled two holes in the seal don't go to far!!!! then put two wood screws in a strip of wood lined up then put a small block of wood in the center and tightend the screws and it will pop right out on mine there was a big washer behind the seal with a quad ring behind that it was gone so good time to replace it if yours needs it
Thanks. How much room do you have behind the seal before the drillbit would hit something else? I would like to go to Harborfreight but it and the bobcat dealer are 70 miles away. I ruined three of the mounting bolts on one motor by putting six-point socket on when I first tried to take the bolts out. It was dark in there and I just assumed they were standard bolts. Luckily I got them out with a 12 point socket. I'll have to get new ones with the rest of the parts. I can't get the bolts out of the other side with a 1/2 in Snapon impact wrench. They must be over torqued or something. Going to Napa to get a 12 point impact socket and an adapter for a three-quarter impact wrench. What is the best method for installing the seal? I would guess it's around 6 inches in diameter from edge to edge. Also there's a white seal on the hydraulic motor that's around 2 inches in diameter. I would assume that needs replacing also. Also there's a big O ring on the axle face that mates with the motor face. Does Bobcat sell a kit that has all of the seals in it? I've read I can use a W 46 hydraulic fluid, is that true. There is a tractor supply 25 miles from here that sells it for $37 a pale. Thanks, you're being a big help.
 

antfarmer2

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Thanks. How much room do you have behind the seal before the drillbit would hit something else? I would like to go to Harborfreight but it and the bobcat dealer are 70 miles away. I ruined three of the mounting bolts on one motor by putting six-point socket on when I first tried to take the bolts out. It was dark in there and I just assumed they were standard bolts. Luckily I got them out with a 12 point socket. I'll have to get new ones with the rest of the parts. I can't get the bolts out of the other side with a 1/2 in Snapon impact wrench. They must be over torqued or something. Going to Napa to get a 12 point impact socket and an adapter for a three-quarter impact wrench. What is the best method for installing the seal? I would guess it's around 6 inches in diameter from edge to edge. Also there's a white seal on the hydraulic motor that's around 2 inches in diameter. I would assume that needs replacing also. Also there's a big O ring on the axle face that mates with the motor face. Does Bobcat sell a kit that has all of the seals in it? I've read I can use a W 46 hydraulic fluid, is that true. There is a tractor supply 25 miles from here that sells it for $37 a pale. Thanks, you're being a big help.
Put a little heat on the bolts to free the locktight
 

antfarmer2

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Put a little heat on the bolts to free the locktight
Just call bobcat they can drop ship all right to your door get the right socket I did a 743 but should be close match up the seals with pvc couplings with threads and the square plug to tap on make the tool as long as needed might have to get a bit of pipe to make it work as for the seals just a small hole in just far enough to get a wood screw started threw a strip of wood with a block in the center to pull it out as you tighten the screws
 

Tazza

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Just call bobcat they can drop ship all right to your door get the right socket I did a 743 but should be close match up the seals with pvc couplings with threads and the square plug to tap on make the tool as long as needed might have to get a bit of pipe to make it work as for the seals just a small hole in just far enough to get a wood screw started threw a strip of wood with a block in the center to pull it out as you tighten the screws
There is a fair bit of space between the seal and the bearing behind it, so it will be unlikley you will damage anything when drilling the seal out.
As for the plate, just use silicone to seal it up. The OEM gasket never sealed very well, they always needed sealant to make them water tight. Don't forget to do the threads on the bolts.
 
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tomagregg

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Jan 6, 2010
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There is a fair bit of space between the seal and the bearing behind it, so it will be unlikley you will damage anything when drilling the seal out.
As for the plate, just use silicone to seal it up. The OEM gasket never sealed very well, they always needed sealant to make them water tight. Don't forget to do the threads on the bolts.
I finally got the oil seals out of the motor carrier, thanks for the tip. On the side that was leaking badly the inside of the seal had been scraped away until it had worn a small hole through the metal. I assume whom ever installed the seal previously had set it in too far until it was touching the circlip. I would assume that the Seal could not move by it's self into that position. The manual states to install the seal with the seal driver until the seal driver bottoms out. Not having a factory seal driver, how far should I install the seal? There really isn't a shoulder for the seal to bottom out on. I want to make sure I don't put it in to deep or I'll have drill it out, remove it, and buy a new seal again.
 

antfarmer2

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I finally got the oil seals out of the motor carrier, thanks for the tip. On the side that was leaking badly the inside of the seal had been scraped away until it had worn a small hole through the metal. I assume whom ever installed the seal previously had set it in too far until it was touching the circlip. I would assume that the Seal could not move by it's self into that position. The manual states to install the seal with the seal driver until the seal driver bottoms out. Not having a factory seal driver, how far should I install the seal? There really isn't a shoulder for the seal to bottom out on. I want to make sure I don't put it in to deep or I'll have drill it out, remove it, and buy a new seal again.
Make your seal driver like I said........can't see it from here but would make sure it is at least flush and not as far in as it was
 

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