Problem with 86 Supra Comp- need help!

[WBL Skier]

Thanks in advance for any assistance anyone can provide.

Boat
• 1986 Supra Comp ts6m
• Ford 351 engine, 740 hrs
• Holly carburetor - It's a 4 barrel, 600 CFM, Model 4160 marine carburetor.
• 13 x 13 three blade prop

Issue
• Boat has recently been moved from MN at 950ft (White Bear Lake) to CO at 7788ft (Ruedi Reservior)
• It was running fine after we did some work in MN where we replaced the fuel pump, fuel filter, and removed the anti-siphon valve from the gas tank. (it was dying of fuel starvation, apparently from a weak fuel pump)
• We drove through 3/4 of a tank last weekend at Ruedi, and it died suddenly. When we tried re-starting it we ran into an occasional clicking, where the boat wouldn't even turn over.
• When it did turn over it wouldn't fire unless we sprayed starter fluid directly into the carburetor. It would die again as soon as it burned through the starter fluid.

[wotan2525]

Clicking sounds like a dead battery or a bad starter.

Can you see gas pumping into the carb if you pump the throttle with the engine off? Sounds like fuel starvation -- why have you not already replaced the "weak fuel pump?"

[kreckley]

It takes dam little fuel pump to make the holly work I would look very carefully at the float bowls and at that altitude it may need rejecting to lean it after you figure out why its not getting gas

[supracompts6m1986]

I'd check the fuel for water. The problem with the boat is the location of the fuel vent, whic is on the port rear of the boat about 18" from the water line. I had a 86 and I had to put a check valve in front of the vent ( it wasn't an easy job) to keep water from getting back into my tank. i replaced/rebuilt carbs every other year until I figured it out.