Leaking rear on GT-14

[cafoose 3,355]

The rear is leaking on the GT-14 I just got at auction yesterday.

 

I jacked it up today and when I spin one wheel the other wheel goes in the opposite direction. The tow valve is stuck closed and fluid was dripping from the rear. It seems like mostly at the case gasket.

 

[daveoman1966 3,762]

As per Pfrederi...I edit my comment.

The wheel spins in the SAME direction tells me you have a 10-pinion Limited Slip Differential (LSD).  This is absolutely normal.   It is designed that if one wheel starts to spin...like in the mud....power is redirected to the other wheel, thereby ensuring that BOTH wheel get power instead of just one wheel as in an 8-pinion differential.   ps...If the other wheel spins in the OPPOSITE direction, that means an 8-pinion differential.

As to the leak....  Your pic shows that the prior owner tried to stop the fluid leak with bondo or some other exterior adhesive patch.  The only SURE CURE is to split the trans case and replace the gasket.   

Edited September 9, 2019 by daveoman1966

[953 nut 55,777]

     I got to wonder what is lurking under that patch that was smeared all over the bottom of the case.        When you fire up the engine does the hydraulic lift work? Have you attempted to drive the tractor at all?

Removing the transmission will require the removal of all the rear sheet metal so you may want to rest it as much as possible while it is together.

[Ed Kennell 38,665]

                                                                      

Looks like they also tried to stop the leak by replacing the  drawbar  hitch with a bolt.

[pfrederi 17,879]

9 hours ago, daveoman1966 said:

The wheel spins in the opposite direction tells me you have a 10-pinion Limited Slip Differential (LSD).  This is absolutely normal.   It is designed that if one wheel starts to spin...like in the mud....power is redirected to the other wheel, thereby ensuring that BOTH wheel get power instead of just one wheel as in an 8-pinion differential.   ps...If the opposite wheel spins in the same direction, that means an 8-pinion differential.

As to the leak....  Your pic shows that the prior owner tried to stop the fluid leak with bondo or some other exterior adhesive patch.  The only SURE CURE is to split the trans case and replace the gasket.   

 

 

I think it is the other way round.  if you turn a rear wheel and the other turns in the same direction then you have a limited slip 10 pinion.  If the other wheel turns the opposite direction it is an open differential 8 pinion type.

[daveoman1966 3,762]

23 minutes ago, pfrederi said:

 

 

I think it is the other way round.  if you turn a rear wheel and the other turns in the same direction then you have a limited slip 10 pinion.  If the other wheel turns the opposite direction it is an open differential 8 pinion type.

RIGHT....  I've edited my post ... Pfrederi is right on this.  

 

[cafoose 3,355]

3 hours ago, 953 nut said:

     I got to wonder what is lurking under that patch that was smeared all over the bottom of the case.        When you fire up the engine does the hydraulic lift work? Have you attempted to drive the tractor at all?

Removing the transmission will require the removal of all the rear sheet metal so you may want to rest it as much as possible while it is together.

I haven't tried to fire it up yet

[cafoose 3,355]

10 hours ago, daveoman1966 said:

The only SURE CURE is to split the trans case and replace the gasket. 

I've never split the rear on a hydro. How do I do it? is it difficult?

[pfrederi 17,879]

40 minutes ago, cafoose said:

I've never split the rear on a hydro. How do I do it? is it difficult?

 

 

It is not hard. Sunstrand manual in the manuals section shows it in detail. You remove the pump and motor as a unit then split the case just like a gear drive.  Lot fewer gears and stuff inside it.  Biggest issue....pulling the hubs.  GT14 hubs are like D series hubs and are much longer than the other WH hubs.  That means there is greater surface area between hub and axles and thus more room for corrosion rust etc,.  That length also means you will possibly break the flange off the hub if it is recalcitrant.  If they are restive I strongly recommend you pull from the back edge of the hub  using something like a flange puller. The long exposed axle length on the GT makes that easier than on the D series.

[953 nut 55,777]

I would suggest you test it as much you as possible before hand so you know if it worth going into.   

I have the transaxle out of my GT-14 right now. The hardest part is the removal of all the rear sheet metal, it is a royal PITA. Once the sheet metal is off you can pull the pump/hydro gear unit off, two hoses and four bolts. This will reduce he weight and allow better access to the transaxle mounting bolts. Set it to the side and then remove the four bolts through the transmission mounting plate.

I know that Lincoln @A-Z Tractor has a GT-14 he will be parting out so you can contact him for parts once you know what you need. If your pump/hydro gear unit is not good a Charger or Electro unit can be used. I did a thread on that several years ago.

The axles and housing are GT-14 specific.

[daveoman1966 3,762]

That Sundstrand tag has 90-1136 on it.  It should read 90-2062  as the GT-14 only used that unit.  What's more, I can see the HYDRO MOTOR attached to the side which is the 2nd giveaway that you are dealing with a substitute power unit.  The GT-14 came with Sundstrand Hydro-Gear 90-2062, as I mentioned.  Some prior owner has swapped out the original unit and put the bigger GT-14 Drive Pulley on it..      

In any case, that leaky trans will need fixin' ....Tough part is getting  sheet metal out of the way, then getting the hubs off.  On SOME models, you MAY be able to SPLIT the trans open by removing the 5 or 6 bolts.  Spread the cases far apart as possible, then reach in with long wrenches and remove the 4 (8-pinion) or 5 (10-pinion) differential bolts.  Then you can remove the internal clips and pull axles out...with hub still on.  

[cafoose 3,355]

51 minutes ago, daveoman1966 said:

Some prior owner has swapped out the original unit and put the bigger GT-14 Drive Pulley on it.. 

I did see that it looks as if someone was messing with it. The hydro seems very clean for the age and the paint seems newer. I have another GT-14 I can use for parts that I got last month for $2 at another auction.