89 supra TS6M problems staying running

[Adam10705]

Hi, I have a 1989 Supra TS6M with a 351 ford, I can start the boat and it runs great while i have a garden hose hooked up to it in my shop so i took it to the river and was boating and wakeboarding for about 20 minutes every thing was going good, the temp was good oil pressure was good then i went to put the boat in gear and it died. I had some trouble getting it started back up and once i did it didnt want to idle but i finally got it into gear and drove back to the dock and as soon as i let off the throttle it would die. After i would wait for a while and let the boat cool off the boat would start up and it would seem to run fine. im just confused why the boat would run great for a while then start acting up, i have played with the timing and carburator it has a new battery and it shows its charging while its running so im stuck any help or ideas would be great.

[SUPRALUVIN]

My Guess Is That You Are Running A Little Rich....had You Left It Long Enough With The Garden House Same Thing May Have Happened.pull A Plug When This Happens And Have A Look...chances Are They Are Pretty Wet And Fouled Up.

[edgewater1]

water in the gas

[Adam10705]

i have leaned it out but it hasnt helped, theres not to much gas in it right now so ill check for water in the fuel, thanks.

[Longhorn21]

I've posted a thread with the same problem and I've had people tell me water in the tank cause the vent on the older supras are located in the back where when you put your boat in the water from your trailer it can go under water and get water in the tank. I would also use ethanol treatment in your tank cause most gas station have 10% ethanol in the gas which is very bad for boats. Ethanol causes condensation in your tank. It could also be your fuel filter getting clogged causing your carb to not be getting the right amount of fuel. Or maybe a vacuum leak around your carb

[Adam10705]

what kind of ethanol treatment do you use and does any autoparts store have it?

[Adam10705]

I emptied my water fuel seperator and it was half water half gas so i drained my tank and changed my seperator and in line filter i also heard that when a coil is going bad once it gets hot it stops sparking so i replace it as well, it is running good in my shop but i was unable to launch the boat because the river is flooded due to the rain last night so well will have to see, thanks for the help any more ideas i would appriciate them.

[Adam10705]

if water is getting in from the breather could i just unhook the hose and plug the hole in the side of the boat?

[Longhorn21]

I use STA-BIL ethanol fuel treatment and I would get it from a boat dealer or a west marine if you have one in your area. If you found that much water in your fuel/water separator than that's probably the problem. I would take it out to the lake after you put clean fuel in it. What ever you do DO NOT plug your breather vent you can only relocate it. If you plug your breather vent it will surely run like crap. From what I understand it is the vent that fuel comes when your tank is full. I would just watch and make sure it does not go under water when launching and keep a full tank of gas when not on the lake

[Longhorn21]

When I say breather vent I mean gas tank vent not the breather valve