Murray rider mower spindels/jack shafts

[Oz_Kioti]

I have a 40" cut Murray rider mower, and I am replacing the two jack shafts (spindels?). The new ones are fully assembled and simply require the top belt pulley and the blade on the bottom to be bolted on.

The units have a zerk, which probably is totally forgotten after the mower is put back into service! However, the zerks invite grease. Question is - how much grease? It's quite a cavity in there. I've already pumped in 16 shots from a manual grease gun into each, and no indications of getting full or grease escaping past the seals. But when to stop???

The old ones were awash with grease when they fell apart, so I don't think they failed from lack of grease. Any thoughts are welcome.

 

[RandyT]

Stop pumping. The cavities are shipped dry from the factory so you are filling a large void with most likely fully sealed bearings that are not going to see any or very little of that large cavity of grease,

 

[Oz_Kioti]

So why the zerk, I wonder?

 

[RandyT]

So why the zerk, I wonder?

Murray did testing several years ago which determined that there is some mixing of grease in the bearings even though the inner seals are in place. I don't think they actually published their findings and the only people that have ever heard of the study are old Murray dealers. Basically it comes down to people that feel the need to grease the spindles are not hurting anything, and the people that never realized they are greaseable are no less for the wear. SBD and Husqvarna do the same thing.