1980 50hp merc stalling

[fastwin15]

Hi there. 1980 50hp merc I have done a lot of work to. This current issue is hard to know where to start to look.

First, took forever to get started - had to put some fuel into 2 of the cylinders to start it. Ran well for about 10 min then just died and can't get it started again. This is the 3rd time this has happened. This last time it wouldn't even attempt to start just 'click'. Fully charged battery to start with. Plugs, wires, coils, switch box, stator all new. Starter rebuilt. Carbs rebuilt (twice!). Could this be a rectifier issue? After all the work I've done its' hard to figure out why the issues again.

Any advice would be appreciated. I just want to fish for cryin' out loud enough fixing!
Here's a pic on the lake about 2 min before she crapped out on me again. Good thing I had the electric motor along!!
You can see why I want to fix and get back out there!

 

[racerone]

Post your compression numbers.-----Did you install a new water pump impeller ?-----Starter must crank fast in order to get spark.----Who " rebuilt " your starter ??

 

[fastwin15]

OK i will check the compression again tomorrow and post. Yes, I put in a new impeller this spring. I rebuilt the starter when I bought the boat 2 years ago - it was full of... mud... yeah, mud. yikes. bottom of a lake maybe?
to answer your next question, yes I got a good deal on the boat

 

[fastwin15]

Update:
Compression numbers were all at 110-120. I tested the stator and rectifier according to the SELOC manual for my engine and both tested fine. Threw in the towel and took it to a local marine mechanic who works on older motors. He declared it to be the stator halfway through me explaining the problem. Turns out the SELOC manual test for a stator doesn't tell the whole story. He used an analog voltmeter for a test that is apparently a better indicator. Turns out he was right and I'm back in action.
Thanks