I am finally getting around to some season ending maintenance chores on my Toro Z587 and I need some advice. First, I can not figure out how to get the dust caps off to grease the front caster pivots. Any suggestions? Next, I want to flush and change the engine coolant (it is a liquid cooled Kawi engine) but the owners manual says to take it to an Authorized Service dealer. I feel like this is within my limited mechanical abilities, (I found the drain plug on the engine to remove the old antifreeze) but I wonder if there are some special issues with this engine that I should be aware of? The owners manual does not even include directions as an option for this service. Thanks!