1995 John Deere 762B Scraper

[Anthony93]

Hey guys so I have a scraper that we recently put a new differential on and it’s constantly leaking from what I think is the breather? It’s a black knob that’s dead center of it and when you put it in 1st or reverse it leaks. But doesn’t in neutral. Why is that? The vin is T0762BX804008. Any advice or ideas would be gratefully. Even a way to possibly trouble shoot it. Maybe my coworker hooked up a line wrong? Thanks in advance

 

[Diesel Dave]

I suspect the brake hose and the differential lock hose are crossed.
Is the hydraulic tank oil level going down ?

 

[Anthony93]

That’s exactly what’s going on. I’ve had to fill that tank and it drops after I put it In first or rev. It doesn’t do it right away but when it revs up is when it happens

 

[Diesel Dave]

That’s exactly what’s going on. I’ve had to fill that tank and it drops after I put it In first or rev. It doesn’t do it right away but when it revs up is when it happens

When you rev it up the axle pump is circulating the oil at a faster rate.

 

[Anthony93]

How do you go about fixing something like that

 

[Diesel Dave]

I assume the tag on the current axle starts with ROAG251 or PEAG251.
Confirm the proper location of the diff lock hose and the brake hose
.

 

[Anthony93]

Ok I will check that thank you

 

[Anthony93]

I have three hoses that are connected there

 

[Diesel Dave]

Including the park brake ,I believe there should be (5) hoses in total connected to the differential.
Park brake, brake, diff lock, axle filter inlet, oil cooler return.
Follow the hose from the brake port, Does the hose end at the brake valve ?

 

[Anthony93]

This is all I can see to where it’s going

 

[Anthony93]

These are the lines

 

[Anthony93]

Where would the brake valve be unless that’s the valve in my pictures.

 

[Diesel Dave]

Where would the brake valve be unless that’s the valve in my pictures.

The brake valve is bolted to the bottom of the cab floor plate, the brake pedal pushes directly on the top of the brake valve.
.

 

[Anthony93]

How do I access this info in the future?
So I checked it out. The top hole I have gear or transmission fluid, the middle is the hydraulic tank, and the bottom just has this white liquid coming out. I swapped the top two and when you press the brake real nasty fluid comes out and again continues to leak. I’m wondering if that bottom hose is the brake line

 

[Anthony93]

There’s 3 lines in a row. On the old one it has two on one side and one on the other

 

[Diesel Dave]

See the pic below.
The top port (axle cooler return) ,could be on either side of the differential housing.
The middle and bottom port functions are as marked.
IF you find that the brake port hose is in fact connected to the brake valve then the brake piston seals and or the dual brake jumper tube are leaking internally allowing hydraulic system oil to overfill the differential housing creating the external leak from the differential housing top breather.
.

 

[Anthony93]

That doesn’t sound good. This differential was a pain to locate and I wouldn’t know where it could be rebuilt. Any ideas?

 

[Anthony93]

I’m not at the machine but is it possible to access the brake system through the floor board? My parts guy quit and so I’m trying to figure this out on my own pretty much

 

[Diesel Dave]

That doesn’t sound good. This differential was a pain to locate and I wouldn’t know where it could be rebuilt. Any ideas?

No warranty from the supplier ?
How many approximate hours would be on the differential since it was installed ?

 

[Diesel Dave]

I’m not at the machine but is it possible to access the brake system through the floor board?

No internal differential components are accessible through the floor board.