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Join Date: Aug 2016
Location: Northern Florida (Almost Alabama)
Re: Mower deck in need of maintenance
An impact wrench should be your "go to" tool for removing and replacing blade nuts, it is what almost any repair shop uses. You can get them in either air operated or electric. If you really have some spare change, get the hydraulic impact ones.
There are a number of tips and tricks one learns over time about repairing decks. First, the self tapping screws that hold the spindles to the deck should be tossed in the spare parts bin. Use a 5/16th inch tap and thread the spindle mounting arms. Then get a longer 5/16th inch bolt and a nylon lock nut and use those to mount the spindle to the deck. Use of never seize is recommended on any threaded bolt/screw. The use of never seize on the bolts for the blade makes it much easier to remove at some future date. Fill the spindles with grease before you mount them to the deck. Another hint is to use a straightedge across the sheaves to ensure that they are all at the same height. On some decks, I've found the best tool is a pipe wrench to grasp the idler sheave arm to loosen the belt.