Shakedown run/1st Dive of the year.

[Tortuga James]

We had a beautiful first day of spring off the coast of NC. Seas were a mellow 2-3 with a 10 sec interval pushed along by a 5 knot breeze. Air temperatures out over the offshore waters was "shirts off".

We ran 42 miles to the stern of the Naeco in 140' of water. It is the furthest offshore wreck in rec limits, and closest to the gulfstream and hence the warmest and usually the best viz. We found 65 degrees and 20-25' of viz and I got one dive in to 132' max. It was a great day.

Tortuga ran well, I had a moderate load, 5 divers and gear. I started with a full load of fuel (200 gallons) and burned 70 gallons for the 90 mile round trip. I made 19 knots at 2200 rpm running at 75% load. Another Captain called me on the radio (as I passed on the way in) and asked what my temp was because he thought I was blowing excessive steam. I was running at 180 degrees, actually a little cool, but the inshore water at the time was 51. I just figured the air must be cool just above that cool water making the exhaust water vaporize.

Come to think of it, she has always steamed more than others, even in warm water. I have checked the guage, she is spot on. The John Deere technician told me that the heat exchanger for that engine is overkill, and some of the commercial boats in the NE had issues getting hot enough to run efficiently.

What do you guys think? Should I track the issue down to see if I truly have an issue?

All in all, I was happy to run a shakedown without the stress of paying customers. I spotted a view things in my system that got rusty over the winter.

 

[sterlingMarineService]

Do you have photos of your boat?

 

[Tortuga James]

Do you have photos of your boat?

Try here: The Vessel Tortuga | tortugacharters.net

and here: Tortuga gets a facelift | tortugacharters.net

 

[Akyla]

James,

I would not worry about the steaming exhaust if all of your temps are in line. The amount of steam is due to the humidity and air temps more than anything else. You are probably correct about the cold water being a major factor of it - just like the advection fog we get when the warm humid air moves in off the gulf stream this time of year...

If it get really excessive during all operational conditions, then I would consider a check of the shower head fitting where the water is dumped into the exhaust as some of the holes could be plugged causing a hot spot and making lots of steam that way. However, I doubt that you have a problem at all.

 

[Tortuga James]

James,

I would not worry about the steaming exhaust if all of your temps are in line. The amount of steam is due to the humidity and air temps more than anything else. You are probably correct about the cold water being a major factor of it - just like the advection fog we get when the warm humid air moves in off the gulf stream this time of year...

If it get really excessive during all operational conditions, then I would consider a check of the shower head fitting where the water is dumped into the exhaust as some of the holes could be plugged causing a hot spot and making lots of steam that way. However, I doubt that you have a problem at all.

Thanks Dave, thats exactly what my mechanic said. The Captain that brought it up on the radio is infamous for putting "thoughts of doubt" in other's minds.

As a part of my 2000 hour maintenance, we are still going to remove and clean the heat exchanger core, as well as raw water cooled oil coolers. Not related, but in this service period is to remove and service my injectors.

There are some advantages to only have one powerplant.

 

[SkipperJohn]

As long as my exhaust is white I dont worry.
Some days humidity likes to condense. Ever notice the dryer exhaust on your laundry dryer at home how it makes a cloud on some days and not on others? It could be atmospheric.