pump

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retiredone

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Jul 20, 2011
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I have a 743b loader, it has had some major oil leaks on the hydraulic system. I removed the engine so I could remove the oil cooler and radiator they were cloged big time. The seal/bearing on pump input shalft is leaking, can this seal/bearing be changed with going in the pump. thanks for any help.
 

Tazza

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Dec 7, 2004
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Sure can, i have done it before.
The bearing is inside the pump, it won't come out with the seal.
Get hold of a new seal from the dealer or loader parts source. Make sure its the right one, not all generic ones hold up to the pressure correctly.
With the engine out, remove the splined coupler on the pump. Remove the bolt and use a puller, do not strike the splined adaptor, they have a taper and key fit, they can crack if you strike it. I get the puller tight then a swift whack to the puller screw usually makes it pop right off.
When its off, remove the cir clip, drill one or two small holes in the seal so you can screw in a self tapping screw. Oil will slowly leak out, but don't be too worried. Using pliers lever the seal out by holding onto the screws. When its out, tap the new seal in. The way i did it was when it was almost seated i installed the cir-clip and tapped it in. This way the seal would only go in as far as the clip did. As the seal gets to the correct point the cir-clip snaps into place. When its done, re-install the coupler and engine. Grease the U-Joints first!!!
Oh, the metal shavings from the drilled holes, they will be flushed out when you remove the seal, so its nothing to worry about.
You should be set.
 
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retiredone

New member
Joined
Jul 20, 2011
Messages
2
Sure can, i have done it before.
The bearing is inside the pump, it won't come out with the seal.
Get hold of a new seal from the dealer or loader parts source. Make sure its the right one, not all generic ones hold up to the pressure correctly.
With the engine out, remove the splined coupler on the pump. Remove the bolt and use a puller, do not strike the splined adaptor, they have a taper and key fit, they can crack if you strike it. I get the puller tight then a swift whack to the puller screw usually makes it pop right off.
When its off, remove the cir clip, drill one or two small holes in the seal so you can screw in a self tapping screw. Oil will slowly leak out, but don't be too worried. Using pliers lever the seal out by holding onto the screws. When its out, tap the new seal in. The way i did it was when it was almost seated i installed the cir-clip and tapped it in. This way the seal would only go in as far as the clip did. As the seal gets to the correct point the cir-clip snaps into place. When its done, re-install the coupler and engine. Grease the U-Joints first!!!
Oh, the metal shavings from the drilled holes, they will be flushed out when you remove the seal, so its nothing to worry about.
You should be set.
Thanks for the info. but my pump has a splined shalft, the coupler with universal joints slides off the pump and the splines are not bolted on service manager at memphis says this can't be the seal will slip over the splines. Don't know what I've got did they make pumps with one a piece shalft. thanks
 

Tazza

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Staff member
Joined
Dec 7, 2004
Messages
16,829
Thanks for the info. but my pump has a splined shalft, the coupler with universal joints slides off the pump and the splines are not bolted on service manager at memphis says this can't be the seal will slip over the splines. Don't know what I've got did they make pumps with one a piece shalft. thanks
With the engine out, the shaft on the pump, is the end machined out? remove any grease and crud, is there a bolt and washer in there?
I have never seen o ne that didn't have a removable splined coupler. It needs to come off to put the seal in the pump.....
If you look up my profile you can send me an e-mail and i can take a picture of the pump i have out of a machine to show you what i mean.
 

cnord

Well-known member
Joined
Feb 17, 2011
Messages
70
With the engine out, the shaft on the pump, is the end machined out? remove any grease and crud, is there a bolt and washer in there?
I have never seen o ne that didn't have a removable splined coupler. It needs to come off to put the seal in the pump.....
If you look up my profile you can send me an e-mail and i can take a picture of the pump i have out of a machine to show you what i mean.
A percentage of 743 and 743B have a Splined shaft, as well as instead of the vane pump on the back, there is a mounting pad with a gear pump. Its a specific serial number break. As for fixing it, it would be the same, but instead of taking off the splined coupler, you just go straight for the snap ring and then pull the seal.
 
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