TOPIC: 68 Merc 1000 - starving after a long run?

I have a mystery on my hands and would love some advice from the folks here.

My outboard starts like a dream, has good acceleration, good top end (around 35mph)- all is working great until.....

Recently, after running it hard (WOT, or pulling kids in a big tube) for a while it starts losing power and stalls.

I first thought fuel delivery, so I changed the filter and replaced the gas with fresh stuff, and checked the fuel line attachment. I would suspect a float bowl if this were a car, but shoot, this puppy has three carbs, one float would't stall the whole thing out.

It sure feels like it's starving for fuel, but then I had another thought - could it be getting hot and seizing up? It will start up within a minute of dying, so this seems like a red herring, but I just don't know what the problem could be.

Anybody out there have a theory?

Thanks,
Glen

Well, not to vent, but here is a long shot for you.

I use the vintage metal merc tanks. I discovered that even though the screw open vent on the cap was 'wide open', it actually was only allowing very little air flow, like almost none. So the motor would slowly drag down as the pumps lost ground to the vacuum building in the tank. If I stopped for a few minutes, all would be fine because of course the little bit of venting allowed the tank pressure to equalize. Fixed the vent cap, all was well.

All that to say, double check that the tank vents are actually venting.

Forgive the early pun.

Thanks. My tank has an open vent hose - but that is what it felt like - pressure starvation.

I ran another tank of new fuel through it and it seems to have cured itself. So, I'm hoping that it was just a little bit of dirty gas. Fingers crossed!

I still could be getting too hot as well. The symptoms fit over-heat as well as fuel starvation, so be sure and monitor the tell-tail or pee-stream, and check the port side cover periodically. It should remain cool or about 100 or less to the touch.
doc