Mercruiser 3.7l 470 fast stall issues!!

My aunt and uncle have a mid to late 80s ski boat with a 470. They had the bearings replaced in the out drive less than 1 year ago. They have burnt the ignition a few times by leaving the key on.. Last weekend I Installed a Initiator II and Flame Thrower coil electronic setup.

We took the boat out today and ran about 22 miles and the engine stalled.. I am not talking about sputtering out of gas or loosing spark it was like some one grabbed the crank and instantly stop the rotation of the engine! When we attempted to start the engine again it was like we had a dead battery. After drifting for about 15 min or so the engine will start right up again, There was a slight knocking from the out drive. We did not make it 150 yards and had another hard instant stall again. After another 15 min of drifting we were able to start up again to get to a safe point to tie off and wait for rescue.

I am currently sitting on a island in the marsh for the night until we can get a tow back to the dock in the morning..

My question is.. Is there a bearing in the out drive that will cause the engine to hard stall. I have done lots of auto work I know this is not a engine knock plus you can clearly tell its coming from the out drive. Knowing very little about the lower end of a stern drive I just cant wrap my head around the fact that it will start up again once it sits for 15 min. Oil pressure is 40 PSI when the engine is running and water temp never above 160 as per the gauges. The battery is brand new and the voltage is 15 when engine is running as per volt gauge.


I can get a lil more information in the morning as far as year and what not.. I just wanted to put this out there..

Ayuh,.... Nothin' unusual 'bout a drive goin' bad,....

Could be the upper gear set, or the lower gear set,...

Only way to know exactly what, is pull the drive, 'n tear it down,....

So we made it back to the dock about 4:30 this afternoon. The drive is a Alpha 1, I did not get the year as I was trying to get every thing picked up from the trip.. The guy that was in charge of changing the bearings in the upper part of the unit came to look at it. We told him that less than 50 miles was put on the unit since the repair and explained what was going on he put the boat in gear and attempted to turn the prop by hand. The prop did spin but was harder to spin than it should, He thinks one of the bearings is not installed properly and will be looking into it tomorrow..