RCK54-22BX Spindle, seal, no grease passing...

[tshep]

On my last sharpening, while shields off, I watched for grease to pass lower seals - only upper on one.
I tried again after job.
OK, read hundred of posts about greasing and the lower shields (cups).
Got any necessary parts, and knocked everything apart, expecting to fine 'hardened' grease somewhere blocking my path - nope. Cleaned shaft out JIC
On full reassembly, the same. I loosened the shaft, set seal deeper in housing, everything I could think of - eventually saw grease pass while really loose and knew I had greased lower bearing, put everything back together.
On second reassembly, again the same.
Grease will pump out top seal, but not bottom.

MY THEORY is that the 'pressure relief valve' effect of the seal on the shaft is much lower on the top than the bottom, and it 'pops' off first.
I may exchange shafts if ever in there again....

Anyone?

 

[arto98607]

On my last sharpening, while shields off, I watched for grease to pass lower seals - only upper on one...............................

I have not worked on RCK54-22BX and do not have one of those, however I have Kubota F3060 with a RC72R-F30 deck.

It has spindle housings where the lower seal is spring loaded and the lip is pointing up in order to keep grease from escaping out the bottom. The upper seal has no spring (they call it a dust seal, but it looks just like a regular shaft seal without a spring) and the lip is also pointing up in order to allow old used grease to exit.

Not sure if the design relies on gravity in taking new lubrication to the lower bearing but in any case it is working great.



The Kubota spindle rebuild kit instructions are very specific on which way to install these seals.


:thumbsup:




Upper VHY seal lets the grease out:

 

[JWR]

I may be ignorant of something important on lubricated shafts but I have never ever looked at (or cared) whether the grease oozed out on both ends or not. To me if there is grease in there under some small amount of pressure "you've done your duty" and need not be concerned whether it oozed out both top and bottom.

I'll be very interested to see/hear posts from others more knowledgeable than myself. At age 76 I'd be astounded to find out that it matters.

 

[arto98607]

No argument there.

My whole point above was to explain how these spindles were designed so that the grease escapes from the top and that way both bearings get lubrication.

It will not work as designed if the spindle rebuilder installs the shaft seals with the lips pointing in the wrong direction.
Bearing lifetime will suffer and a seal will be pushed out when you pump in more grease.

 

[tshep]

The upper seal has a limiting depth flange - one way, one depth only.
The bottom seal is unflanged, and will set either way at various depths, at least until shaft tightened.
I put it in rubber in, metal out.

There are very long threads/100's posts about 'filling the grease cup' and to 'exit hole', which I am calling a shield - I don't think it is made to be filled, and that's just secondary to protecting the shaft from grass, etc...

But, my other two did exit both ends - just this one shaft and it's mating pulley mount (where the seals ride) act differently from the other - but parts all look fine. And will allow exit before torquing.
At one point I thought that maybe this shaft's blade mount flange was just barely sealing against the excess rubber on the seal's metal side - so I tried disassembly and pushing seal in a bit more. After a bit more loosening I did get dual flow, so I knew it was at least well greased once! After torquing back to only upper again.

I'll give it another look next season.