Engine Steam

[Mike]

For over a year now I have been trying to decide if the steam I get from my exhaust is normal or if something is wrong with my engines. I have 1992 FWC Mercs with lift mufflers. The steam dissappates within 10' - 15' behind the boat and is only there while under load (I typically only run at 3200 RPMS), both engines produce the same amount.

This past weekend it was more than normal but I was contributing it to cooler water temps, higher air temps. All manifolds and elbows are new, water flow is good and engines run at Starboard 160, Port 180.

The starboard engine does have a little trouble reaching WOT and I will have that look at over the winter. Any ideas on what to check for for the steam and as well what to "tune-up" for the WOT issue?

 

[sbw1]

Steam is normal and varies with weather conditions. Don't worry about it. The WOT issue could be a tune up or improper propping. Try a tune up first if the boat needs one or you do not know when this was last done. If that does not work, you need a prop shop. Do both props. I do wonder about the difference in operating temps. Are you in salt water? Are the t-stats in good shape? Do you have a heat exchanger issue?

 

[mrsrobinson]

I had the same steam worries when we purchased ours. I'd hear comments like "wow, your engine exhaust steams, ours does not, get it checked out". After doing my research I concluded this is normal.

On the temp concern, put a heat gun on the thermostats to make sure your gauges are true.

 

[Mike]

I replaced wires, caps and plugs the beginning of this year. I did not do the coil, maybe it is time to. T-stats are new. The higher temp engine is the port, no water heater connection, i've been told the engine (in my case the starboard engine and the one running at 260) connected to the water heater will have more capacity of 50/50 therefor cooling a little more.

 

[mrsrobinson]

The one connected to a water heater will run slightly cooler, but not 10 - 20 degrees cooler.

 

[roadkingh1]

Mike, I have the same problem on my starboard side and that I have steam coming out about 10 to 15 ft behind the boat. About the same time that I notice this happening I also noticed that the water coming out of my exhaust was not as much as the port side. I know that it was fine earlier that year. When I mentioned the steam to a mechanic his first reaction was, "have you ever changed out your raw water impellers". What is happining is that the little water that is hitting the exhaust is not enough to cool down the exhaust, therefore causing steam. At first I thought it was smoke, but smoke would have lingered instead of disapating immediately. I live in south Louisiana so the water is cooler this time of year.

For over a year now I have been trying to decide if the steam I get from my exhaust is normal or if something is wrong with my engines. I have 1992 FWC Mercs with lift mufflers. The steam dissappates within 10' - 15' behind the boat and is only there while under load (I typically only run at 3200 RPMS), both engines produce the same amount.

This past weekend it was more than normal but I was contributing it to cooler water temps, higher air temps. All manifolds and elbows are new, water flow is good and engines run at Starboard 160, Port 180.

The starboard engine does have a little trouble reaching WOT and I will have that look at over the winter. Any ideas on what to check for for the steam and as well what to "tune-up" for the WOT issue?

 

[Jimmy Buoy]

I was concerned as well with steam from my Amberjack, but I noticed from the boat photo on the Sea Ray website (archive files) that the same model in the brochure has the same pair of steam trails as mine.

 

[HighFlight2k2]

Can you replicate it in the slip? Does the steam smell? I had the problem when I first bought my boat. Dealer tried to say it was normal until I stuck their nose in front of it and it smelled like anti-freeze. Turned out to be an exhaust manifold. It still steams, but doesn't smell.

 

[Mike]

No smell, just steam underload. No steam at idle.