I might have an answer to your "why" question.
In the old days, yeah I'm old enough to have experienced them, there was a school of thought that you remove the factory plugs, screw in a zerk, grease the item, remove the zerk and put the plug back in place. Not many people bought into that theory, but some did. This might explain it, but regardless, if the machine were mine, I would remove the plug, put a zerk in its place and keep it greased.
I just got through rebuilding the spindles due to the previous owner never greased them. Keep them greased about every 25 or 30 hours and you will go a LONG time before rebuilding the spindles.
My $0.02,
Larry
Just thought I'd thow something out there to incite some debate in this thread:0)
I've never owned a GH ZTR, but I have owned two previous lawn tractors both of which had grease zerks on the spindles. As I shopped last fall for a ZTR, I had MANY different brand dealers explain to me the reason why most of the "Commercial" ZTR's I looked at(most having cast iron spindle housings versus aluminum) did NOT have grease zerks either on the spindles or the caster wheel housings(another thing both of my lawn tractors had).
Here's their story and they are sticking to it(even the Gravely mechanic at my dealer):
For many, many years(since the early 90's) 99.9% of the lawn cutting machines that you purchased with grease zerks ALL had "sealed bearings". The reason they put zerks on the spindles and wheels was because consumers "demanded the ability to maintain their bearings' lubrication" and the zerks were basically a "placebo" to satisfy the consumer so they would buy that manufacturer's product(because it sported grease zerks). By design, when you added grease.....it "filled up the housing AROUND the bearings" but NONE of the grease ever touched a ball bearing(because they were "sealed")!!!!! All the 6-7 major brands I looked at(Grasshoppers were a wee bit out of my budget) all told me the same story and it took a while to "convince me" to by a several thousand dollar lawn mower that didn't have grease zerks. My Gravely mechanic told me every spindle rebuild/replacement he had performed over the last decade revealed sealed bearings in spindle housings that had grease zerks and he even showed me one that he was currently re-building and indeed it had zerks....AND..."sealed bearings". That, plus the fact that Gravely gives a 3-Year/1,000 Hour Warranty on my spindles(a specific spindle warranty) finally gave me a "warm & fuzzy" to go ahead and buy a ZTR without zerks(a Comercial model ZTR). He(the Gravely mechanic) said.....yeah they will "eventually" wear out all bearings do, but you should expect between 1,500 and 2,000 hours of service out of these "industrial heavy duty service cast iron" spindles. At an average of 50Hour/year mowing my 1.5 acre lot that would be about three lifetimes for me:0)
Soooooooo, all that being said.......maybe you guys should discuss grease zerks and sealed bearings with your Grasshopper dealer(and mechanics) and see if Grasshopper has also gone the route of giving you a "grease zerk placebo" if your machine was manufactured after 1990. And.....what I was told was that if indeed your grease zerks delivered grease "into the bearings" that you had better be VERY CAREFUL to not "overfill them" or use an "air grease gun at high psi" or you will rupture the upper or lower seals in the spindle housing allowing dirt, grime & water to enter....doing more harm than good in regard to your spindle bearing longevity.
OK....let the debate begin!!!!!!!!!:0)
