3.0 Mercruiser, shakes then stalls

[Cychocitty]

I have a 1992 mercruiser 3.0, it starts fine idles fine and goes into gear fine, but then as I'm driving once I get above 1200rpm it stalls. If I accelerate harder it stalls more violently and will shake as well.
Sometimes it will make a screeching sound when accelerating fast before it stalls. It feels like something is grabbing the engine and stopping it. After stalling it will start back up perfectly and idle fine, without any noises.
Any ideas on the cause?

 

[ThomW]

I have a 1992 mercruiser 3.0, it starts fine idles fine and goes into gear fine, but then as I'm driving once I get above 1200rpm it stalls. If I accelerate harder it stalls more violently and will shake as well.
Sometimes it will make a screeching sound when accelerating fast before it stalls. It feels like something is grabbing the engine and stopping it. After stalling it will start back up perfectly and idle fine, without any noises.
Any ideas on the cause?

Have you checked the timing? Distributor cap may be turned out of whack...

 

[Cychocitty]

Have you checked the timing? Distributor cap may be turned out of whack...

I will check that thanks! It does rev up no problem in neutral, not sure if that changes anything.