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My Engine Blows Steam Out the Exhaust

Steam appears as billowy white smoke that disappears and has low odor. If the white smoke has a strong fuel smell it might be excess fuel burning and not really steam.

Steam is usually noticed on boats that have direct exhaust. Boats with through-prop exhaust can steam too but it would only be evident if the boat were not in the water.

A little steam is normal. All exhaust will show a little stean now and then especially on cold mornings. If you get excessive steam it may indicate a problem.

Two basic things can cause too much steam.

1. Overheating
2. Leaking Exhaust Manifolds, Risers or Gaskets

1. Overheating causes the exiting exhaust water to turn into steam. A bad Water Pump, a plugged exhaust manifold or elbow or even a bad thermostat can cause the engine to run hot and steam.

2. Old exhaust manifolds and exhaust elbows can get plugged with rust or the can develop internal water leaks. If the xhaust is bad to the point that it is causing steam, they should be replaced ASAP. Bad exhaust will ruin a perfectly good engine.
















Safety
Boats can explode. Moving parts can rip off your fingers. Hot exhaust can burn you to the bone and props can slice you up. One spark near a battery can cause an explosion. You can never be too careful. Remove the battery from the boat before working with fuel. Always disconnect the batteries negative terminal first. Clean up any spilt fuel and let ALL of the fumes dissipate before installing the battery and starting the motor. Pulleys and Belts can grab your clothes and hair. Don't wear loose clothing and keep your hair up under a hat. Always wear safety glasses. Be smart.
Sterndrives.Com
Change your Alpha Gear Lube
Change your Bravo Gear Lube
Why does my drive lube have white streaks?
Why does my drive lube have gray mush?
Replace Your Alpha One Water Pump
Replace your Alpha Gen II Water Pump
Rebuild your Bravo Raw Water Pump

Troubleshoot & Replace your Alpha Shift Cable
Troubleshoot & Replace your Bravo Shift Cable

Replace your Alpha One Bellows & Gimbal Bearing
Replace your Alpha Gen II Bellows & Gimbal bearing
Replace your Bravo Bellows & Gimbal Bearing
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Water is leaking into my boat from the transom

Replacing your Trim Sender Switches
My Trim doesn't work but my Trailer Switch does
My Trim Gauge is Pegged

Rebuild your Alpha One Upper Driveshaft Housing Assembly
Rebuild your Alpha One Lower Gear Housing Assembly

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My Engine blows Steam from the Exhaust
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