My 1980 150 hp V6 black max ran for about 8 minutes today (on the muffs) then it turned off and would not want to start back up. It did not overheat, the block temp was 114 degrees farenheit, and it peed like a horse. I did have trouble starting it up. I have done the following within the last week, rebuilt carbs, rebuilt fuel pump, replaced all fuel lines and filters incuding bulb etc with merc parts. I took a look at the reeds they were fine. I was running it on a portable gas tank (its vented so no vapor lock). I have spark on all cylinders, new spark plugs as well. Compression is 95 -100 on the cylinders (good enough for a 30 yr old engine). SO I have basically redone the whole fuel system and it turned off and wouldn't start back up. Any ideas would be appreciated.