Bevel Case Oil Seal

geohorn

Well-known member
SUPER Site Supporter
My M4700DT developed a front axle oil leak at the left bevel gear case oil seal (item 8. Notice the pic shows the seal to be a two-piece seal..but it’s actually a one-piece…similar to a common wheel bearing seal or any axle seal.)
I ordered the parts and disassembled it and I’m attempting to reassemble it. but the lower case will not slide up onto the upper. I had pressed the new seal into position with the metal “base” down..into what is labelled the “front” gear case. (The rubber lips facing up…as that is how the old one appeared as it came out.)
It appears the oil seal must now slide up surrounding the bevel case…and refuses to do so by hand….the inner metal surface of the seals’ base is rubber-coated it appears to tightly-grip the bevel case “post” or “stub” (whatever we should call it)…and it’s such a tight fit ..it seems to be the issue. I’ve tried pushing the front gear case onto the bevel case using a floor-jack.
It is refusing to the point of the floor jack actually lifting the front axle and tractor completely off the jackstands supporting the front of the tractor.
The WSM does not have a good illustration (as seen below) but only mentions to pay attention (note direction) of the seal. (I installed it with the lips facing up and the metal base of the oil seal down…into the front case …because that is how the old one came out.)

I’m beginning to wonder if the new superceded part number shouldn’t be installed with the metal base UP and the Lips DOWN…to facilitate the unit sliding upward during reassembly.

Anyone ever do this job…??
 

Attachments

  • CA5013B9-986C-4C3C-9924-C2C4BF301441.png
    CA5013B9-986C-4C3C-9924-C2C4BF301441.png
    1.7 MB · Views: 4
Last edited:

geohorn

Well-known member
SUPER Site Supporter
OK…figured this out WITH THE HELP OF DOUG AT MESSICKS! (My local Kubota Dealer is full of Poop and nearly cost me serious money.)

The illustration above indicates the oil seal is TWO PIECE… but a new seal has a superceded PN …which can mislead you into thinking the new seal (which comes completely assembled in the bag) is a ONE piece seal. This can cause you to think THAT is the reason for the new PN.

NOT!

What happened is when the lower gear case (Kubota calls it a “front” case) is dropped off the “bevel” case…. the installed oil seal can separate into two parts…with the main portion remaining in the lower case…. and the Inner metal base remaining on the bevel case “stub” (my term.)… and it well NOT be apparent. The inner metal base will appear to be a “step’ machined into the bevel case stub.
When the portion remaining in the lower case is removed…it will appear to be the complete seal. But it’s NOT.

And when a new seal is put into the lower case…it WILL NOT be capable of sliding completely up onto the bevel case stub …because the inner-metal-base will have stuck onto it as a “ring” of steel.

That RING must be removed (I used large channel lock pliers) before the lower case with the new seal can be slid up/onto the bevel case stub.

BY THE WAY; … the new seal is installed with the rubber lips facing DOWN! …and the metal base UP…to slide onto the bevel case stub.

Hope this helps.

Here’s a pic of the point where I discovered the problem of the lower case not being able to slide up onto the bevel case stub:
 

Attachments

  • 28FC9220-8F1B-4B57-9B71-6C131ECF4878.jpeg
    28FC9220-8F1B-4B57-9B71-6C131ECF4878.jpeg
    757.6 KB · Views: 9
Top