Has anybody used the MSD starter savers.Having trouble tearing up starters and ring gears on my 540 motors.can you use the starter /savers with the stock mercruiser ignition and distributor .Total timing on the motors are set at 36 degrees around 2800/3000 rpm and retard to 20 degrees at idle.Already trashed four starters and a flywheel.

Had a customer put them on a set of 572's in a 32' AT. No issues. He is at 35 degrees FA.

I have Merc distributors with 24 degree modules and run a total of 36* advance at 3000 in my 540s (9.3 CR) idle timing is 36*- 24*= 12*. Four seasons and no issues
Had a problem with my previous engines...three ring gears also found a leaky gasket between my manifold and elbow

That is my brother's boat. He is using the MSD 8984 Starter/saver. His timing is locked out at 36 degrees and is only allowing 10 degrees retard at start-up. He has about 45-50 hrs on his 572 ( 9.5:1 ) motors and has never had a starting problem yet. He can cut the blue wire to allow 20 degree retard if need be.

The merc T-bolt 5 ign does this too, a lead goes to the resistor terminal. Basically locks timing back until starter is disengauged. You must have the extra terminal on the starter though. Msd mechanical distributors are junk !!! Just wire in the MSD box with rev limiter with merc T-bolt and module. You may not be able to make it work unless you use the T-bolt 4 Dist., but may wire in the MSD starter device.
Msd Stops MSDing at around 3000 RPM'S and I have seen no speed increase with it. Maybe a Delco Voyager Ign SYS could be used, same as on a car with screens and all ! BBB

When bendix hangs up, this happens, also when HT starter trys to turn partially frozen motor(hydrolocked) this can happen too.
There are several PMGR style starters out there.
Make sure that it's a real HT with Delco Remy cast into the nose piece. Anything else may contain bushings instead of torrington roller bearings, as well as other issues, and is really not going to give the service life of the Delco nor handle the abuse.
I've changed at least 100 starters, and been inside of most of them just to see what went wrong, and which are made better. Even the best starter will not handle getting wet or submerged well. If one ever gets wet take it apart clean it, inspect it lube it test it and put it together and on.
It may sound crazy, but you will know it's good and may have saved it. As well as saving you money.
The manufacturers are installing starters that are cheap to produce, and the parts guy might be selling a universal starter , but it may not be what you really want to do. BBB