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steam in exhaust

I have a Donzi C22 with a 454 that I have recently bought. Today I had a chance to look at the boat today with the idea of dropping in the lake. I noticed after the boat ran for several minutes it started to steam at the exhaust. I don't think that's normal, so i started to look into it. The water pump is good and water is coming out of the exhaust The steam is coming out of both exhaust so I have all but eliminated a head gasket and am thinking intake corrosion.....there is corrosion of some of the water pipes at the front top of the engine, presumably due to some running in salt water. Does the intake corrosion sound reasonable for this engine?

Quote:

Originally Posted by ph1971 (Post 4648158)

Steam is normal

thank you.... it’s not a small amount of steam, but I’ve not owned a BBC before so appreciate your comments...I have a SBC in mother boat and don’t see it....sounds like a characteristic of the BBC?

The amount of steam will be directly related to the lake water temp and air temp. Colder water and colder air will create more steam.
If its an abnormal amount of steam, then I'd suspect internal cracked exhaust first.

Quote:

Originally Posted by Griff (Post 4648177)

it does seem excessive... I’ll pull the intake and see if corrosion has set in. Thank you

What is the engine temp gauge showing when it's doing all this steaming ?
What is the lake (?) water temp ?
What is the air temp and relative humidity ?
Are both exhausts showing the same amount of steam ?

steam out the exhaust depends on air temp for one and and the other can be cold water temp mixing with the hot exhaust. Cold air hot exhaust can produce steam for one example. But steam can also be a form of water and or condensation in the combustion chambers and or a form of water hitting the exhaust valves. Pull out your spark plugs, look for rust and or water on them, Disable the ignition for spark crank engine over to see if water purges out or a mist of water. .Pressure check your exhaust and if applicable change your riser gaskets to new - make sure your sealing surfaces are really good for the new riser gaskets again if applicable.

Quote:

Originally Posted by madbouyz (Post 4648274)

the temp gauge shows 180 so nothing unusual there. It was 60F...was running on hose, but earlier in the lake the temps were 70F water.

Quote:

Originally Posted by BUP (Post 4648293)

indid a compression check and had about 130ish on all but cyls 4 and 6...and a few had moisture on them. I also noticed some water in the bottom of the exhaust manifold.

Ive decided to pull the engine and check the intake manifold and head gaskets. Probably should have the valves ground and check for head crack while I am there. Am I missing anything?

should be 160 temp if your app is 1996 and above regarless of carb or efi.---OEM stock Mercruiser