How do you change the blade on a skilsaw 5500

SOURCE: How do I change the blade?

use a hard board to hold blade tight

rem: unplug power cord... thats how i've had to do it
at times

SOURCE: How to I change the blade on a skilsaw cicular saw?

The blade is USUALLY held by a LEFT HAND thread bolt. Sometimes they have a diamond insert in the blade that must be removed if the saw has a matching boss on the arbor. If the saw has that, you punch the insert from the blade and engage the diamond over the boss on the saw then put the clamp washer on top and then install the bolt.

OFTEN there is a button near the blade are to push in to "freeze" the arbor so the bolt can be removed/installed. These are USUALLY left hand threaded bolts.

SOURCE: Need lower blade guard for Skilsaw Model Model 77

Yes I do Know where, here you go !
http://www.toolpartsdirect.com/skil/skil-34.html

SOURCE: How to change blade on skilsaw 5380

on a circular saw
pull the power lead from the plug
using a screw driver , place the blade between the teeth and turn until the screw driver is jammed under the plate
use a ring spanner and undo the nut that holds the blade on
pull the blade out and fit the new blade with the direction arrow in the right direction
replace the plate and the bolt do the bolt up tight
rotation will tighten it up
some blades have a hole in the blade in which to insert the screw driver to hold the blade , or a lock lever behind the cover to hold the armature shaft while changing the blade

SOURCE: Skilsaw 3310, motor turns on and runs blade does not. Blade changed and tight on shaft

if the blade is mounted correctly and tight and the motor is running, the only other explanation for a failure is a stripped gear in the gear box