If you've ever wondered where that shriek comes from when you're revving your older Briggs flathead, this post is for you. Briggs went to a "modern system" some years ago using a ratchet type starter. The starter pawl used on old-style Briggs engines is actually fairly complicated and uses ball bearings as an "on-off" mechanism to rotate the crankshaft to start the engine. Once running the ball bearings release.
The images below show how the pawl is assembled. There are six ball bearings inside the pawl. If the pawl is disassembled for inspection, simply clean up the balls but do not oil. The cover needs to be securely reinstalled, or at speed, it will come off.
There is an oiler hole located at the top of the pawl, as shown below. The manual says to lubricate with one (1) drop of synthetic oil. I'm not too sure why it has to be synthetic, maybe for longer life? Who knows....
Looking from the base up, the inside of the pawl is machined to fit around the crankshaft extension. If you have a crankshaft that DOES NOT have the roughly 2" long extension, you CANNOT use this style starter. A couple of pulls and the pawl will be in pieces without the support crank extension.
This image tries to show the inside of the shaft and the threads. Threads, of course, need to be clean. It is not unusual for the starter pawl threads to pick up some corrosion, dust and dirt, making it more difficult to remove the starter.
So where does the shriek come from? Like everything Briggs does, parts are designed to perform within certain design parameters to make the products they produce cost effective. The starter pawl is NOT designed to handle extended run periods without lubrication and, more importantly, it's not designed for extended periods of revs in excess of 4500 rpm.
Eventually, heat and friction cause the pawl to lock up against the crank extension sounding first as a shriek. It's safeguard is to blow apart sending the ball bearings everywhere.