Stbd motor producing steam and temperature rising

[Gary Dodge]

Hi all. I have a pair of 6bta’s that have 1700 hours. My motors have a marine age of 13 years. I cleaned both seawater sides a year ago using Tony’s protocols. Tony’s tech’s rebuilt both of my seawater SMX pumps a few months ago. My stbd motor is still producing steam and the temperature rises a cruise rpm. What’s my next step?

Topic

[Gary]

I’m back. I still haven’t resolved my issue with my stbd engine with steam and engine temperature rising.
I have run the motor at the dock at 2400 rpm and can feel water rushing through the hose between raw water pump and after cooler. The hose feels the same while motor running or off. I have removed my fuel coolers so the hose is reinforced.
Tony’s question about the pickup on the hull, the hull has what you call a forward motion pick up. It is designed into the bottom and thru hull comes through the top. No screens. No scoops, I have seastrainers.
Rob’s questions, I have elbows that I believe are mixers. Shower head type. I took it off and had Marine exhaust inspect it. They found no blockage in either the gas or water side. They said it looked pretty good for nine years old. No sign of any salt water damage to turbo exhaust so Must be draining correctly.

[Tony Athens]

Gary,

Are you saying you have NOTHING on the bottom of the boat other than a “thru-hull”?

Nothing like some type of “forward motion pick-up” or scoop?..

Tony

[Rob Schepis]

What do you have as to wet exhaust, mixer, etc? How is it oriented, does it self drain, has it been inspected? Any pics available?

[Rob Schepis]

It’s not that the hose coming out of the pump is “compromised” ….. you want to feel that hose at high rpm (high flow) and see if it gets real hard (pressurized) indicative of blockade further down the line.

[Gary Dodge]

I noticed a small amount of steam from the stbd engine a year ago this month on a trip to the Bahamas. At that time my engine temperature was normal. Over the year the amount of steam increased and temperature started to rise last December.
My two inch raw water hoses were replaced two years ago. I have never lost an impeller.
The boat was hauled in March and had new bottom paint. I have a diver clean the bottom once a month.
My pickups are straight thru Hull with no screens. I have seastrainers and just replaced the stainless steel baskets in March.
The fuel coolers have been gone for years per your article to get rid of the block and fuel coolers. The hose off the the raw water pump to aftercooler is not compromised.
I will run the engine at 2400 rpm like you asked and check the other raw water hoses.
Thank you for your reply.
Gary

[Tony Athens]

Is this something new? What did the them used to be vs. now?

Any chance you a have flow restriction on the seawater side? Have you ever lost an impeller in the past?

What kind of pick-ups do you have under the boat? Sea strainers?

Do you have a fuel cooler with the soft hose right after the pump? See if that hose gets hard / tries to expand at the dock when you rev up the engine in neutral ( idle vs. 2400 RPM)..

Tony

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