GC1705 - dual front axle leaks. Diagnosis, parts, and cause?

[5030]

Usually, once a radial seal starts leaking, they don't quit leaking until replaced. The other issue is how the front axle is vented and if that vent is plugged with trash. The axles have to breathe (either by dead air space above the lubricant) or via a to the atmosphere vent or the axle will become pressurized as the lubricant warms up. Why the differentials on your car or truck have a vent hose on them. If they weren't vented to the atmosphere, the outboard axle seals would leak. In reality the radial seal on each outboard has a very small contact area so any vertical movement in the outboard can cause the seal to weep lube oil. I've replaced a number of them on my large Kubota's and in every instance, the kingpin bushings were shot which allowed the vertical movement of the outboard. Easy to replace to the correct sized bushing driver or appropriate size socket and hammer and remove the worn ones is a simple matter of driving them out with a punch.

 

[Dmacleo]

the fill plug on the GC series also acts like a vent. make sure to clean it out well.

 

[not2old]

The seal leaking is always caused by other issues that allow the outboard to have excessive vertical slop in it. Usually the kingpin bushings are shot and they are easy to replace. Just replacing the seal won't cure the issue as it will start leaking again as the seal cannot seal with excessive slop in the outboard. I suggest at least buying a set of kingpin bushings before taking it apart. it the kingpin is also worn (unlikely bit could be, that will also need to be replaced as well. The bushings are inexpensive and easy to replace. Kingpins, not so much but you won't know until you take it apart. I would order the bushing in advance in as much as parts availabilty is a crapshoot today.

Easy to diagnose too. Loft the front axle and try wiggling the wheel and kingpin vertically. If there is slop (wiggle), the bushings are shot and if it's been like that for a while, maybe the kingpin as well.

When replacing the seals I didn't check things out very thoroughly but now over 1000 hours and haven't leaked again after more than five years. Sometimes you get lucky.

 

[5030]

On either of my M9000's I've never had a radial seal leak.

 

[edgarrian]

I have over 600 hrs on my 1705 that i bought new in 2016. I haven't had any leaks yet. I won't loan it out b/c i know how others really dont know how to operate. I have grown up around equipment all my life. A quick loan out can turn into a real PITA

 

[Joel/ak]

Had to replace the seals on our 1705 around the 300 hour mark also. A few snap rings are a PIA but relatively easy.

I had the luxury of tearing it apart, inspecting everything then I ordered what I needed.