Starter shimming is one of those operations that we should all be participating in at some level, but few of us do. Normally when you are swapping a starter, you are stuck somewhere, annoyed that you are doing it, or generally in no mood to take extra time to do anything but jam ass the bolts in and hit the road. While that may get you on the road quicker at that instant, the long term effects could be negative. Over time, an ill fitting starter can chew up the ring gear on your flywheel or flexplate, leaving you stranded again and this time, in far worse shape.
As you would expect, the process is not rocket science and even involves the use of a paper clip as a makeshift feeler gauge. It is 10-15 minutes work tops and it allows you to have 100% peace of mind that your starter is engaging enough of the gear and is doing so without slop. Even if you are on the side of the road, stick that puppy on and then complete this process when time and safety allow.
This video is good basic tech to start a Friday that we KNOW you are going to be non-productive on. If you want to rebel against the man and not do actual work today, at least learn some good car stuff!
Press play and learn hose to shim a starter!