Zero Turn Mowers

I have a Z246, about 2 months old. I read somewhere that the mower usually doesn't have full grease and "just enough" from the factory. My first mistake was to use a mini grease gun. Went through 3 tubes and still saw no grease coming out. My neighbor loaned me his full size and after a few pumps, the grease came out. I greased both spindles, both front wheels, and "tried" to lubricate the blade spindles. The left side took the grease well but didnt see anywhere where it came out. The throttle side would not take any grease. I took the grease fitting off, attached it to the gun and it came out. screwed it back in, would not take any. I did have issues with the end of the gun completely attaching to the fitting AND THEN had the hardest time getting it off. Any ideas please...

Tom