Slight miss/gray white smoke
 

Hey guys having another issue with my 03 Launch SSV, Notied yesterday after about 4 hours of use, while pulling up a skier a slight miss untill on plane then goes away, problem repeated for about another 30-45 minutes then trailered it. Boat idles fines has no loss of power and also noticed some white/gray smoke while on the water thoughts?

Things I have recently done, in the past 50-75 hours: 250hours total on boat

Replaced both fuel injectors (this was the problem last time that was finally solved)
Replaced fuel pump
Fuel filter replaced 4-14
Fuel lines cleared
Fuel tank emptied and cleaned, Fuel pickup line checked and mesh guard cleaned
Just changed the oil and filter before the weekend

We've had a lot of rain Lately down here in Texas and I filled the boat up after the first day of sun, When the issue started I would say I had at least 8-10 gallons of gas in the tank.

I've also noticed that I seem to be burning through 40 gal of gas in about 5-6 hours which is more than usual with the old injectors. Possibly running rich? Have I fouled spark plugs. Boat was difficult to get started when I got it home and put on the hose. Would new fuel injectors mess with the computer?

With white smoke my money is on a leaky exhaust manifold gasket. Thats what was the source of my white smoke anyways. I don't know how to confirm that without removing the manifolds unfortunately.

Sure it's not steam coming out the exhaust. Most boats do it, is it a mist or a cloud of smoke.

Watch this quick clip, at the very end you can see the steam coming out the back of the boat. Is this what yours looks like. If it is they all do it.

http://www.wakeworld.com/news/videos...twelker-7.html

Yeah that's what it looks like. And doesn't seem to smoke while it's on the hose.

My 2006 Supra 24v does the same thing and my old nautique 95 super sport did it.

Your boats fine.

it won't likely heat up to operating temps on the hose. your guage reads 160* but thats at the top of the engine, usually on the intake. Much higher temps at the exhaust. How old is your impeller?

I noticed a LOT of steam and had lost a few vanes on one several years ago.

This miss is probably due to moisture and corrosion in your distributor cap,... The missing may also cause poor combustion and the steam....

Pop the cap off and look for water and or corrosion on the rotor and the cap.

Did supra run catalytic converters in 03?? If not, the steam is not normal. That is only normal on an engine with catalytic converters. (Because an engine doesn't create H2O under normal conditions. The CC converts hydrocarbons into CO2, and H20. The heated H2O is the steam you see on the newer boats with CCs)

White/gray smoke/steam and a miss, on a non catalyzed engine, could indicate a head gasket problem. Or it could be something as simple as a distributer cap, and the smoke is just fuel vapor. It could also indicate high cylinder temperatures, and you may want to make sure you are cooling correctly. (Check impellor, kinked hoses, etc)

An engine that is running high combustion temps, will leave a pretty steady trail of gray smoke.