48 DA Owners Club

Kurt Kesel said:
Couldn’t,t you add a variable speed fan to push more supply air?
Click to expand...
In theory, yes. Bigger fan equals more air. But the factory air flow problem does not stem from the size of the fan, the factory problem is the route of the air. It's kind of like blowing air thru a straw, the harder you blow, the more air will flow, but it gets to a point where no matter how much harder you blow, you only get a minor increase of air flow. The unit is place so close to a wall that it is very hard for the return air to move efficiently thru the unit. Secondly, the existing factory fan is very noisy, a bigger fan would compound that problem. Also, I suspected by never verified that I think there is some short cycling going on where the air coming out the main vent is being quickly sucked back in the return vent. The return air should be "Hot" air, not air that was just discharged cold.
 
Shaps said:
Unfortunately, I don't. Just recognized the message. If you call KVH support they will help troubleshoot up to a point but you'll definitely need to be able to interact with the ACU via a terminal emulator.

If you were closer I'd come help in person
Click to expand...


UPDATE:
When I returned to the boat last week since this problem occurred. I fired up the TV antenna and all worked as it should. Go firgure... it must have been from the storms that rolled through the area. What is confusing, we have had storms in the past that would cause a delay in service but it never when into an idle mode.

JB
 
JB MARSHALL said:
UPDATE:
When I returned to the boat last week since this problem occurred. I fired up the TV antenna and all worked as it should. Go firgure... it must have been from the storms that rolled through the area. What is confusing, we have had storms in the past that would cause a delay in service but it never when into an idle mode.

JB
Click to expand...

Love it when problems fix themselves!
My fear is that these gremlins come back. That was what happened to me with my antenna, hopefully you are in the clear. Just keep an eye on it, if it takes longer to boot up than what it used to, etc.
 
Been pretty quiet here this summer. What’s happening with fellow 48’ers? Post your summer fun…. I did 15 days in the Bahamas what had everyone been up too?
 
Did a week long trip out to Nantucket and Martha’s Vineyard. It was a perfect week in every way.
Going to Block Island this Thur-Sun.
 
Headed out Monday for the Chesapeake Bay. Going to Cape Charles, Norfolk/Portsmouth, then Regatta point on the way home. 375 miles in all. 600+ gallons of fuel :eek:

We love going to the Norfolk area. Nothing like following an aircraft carrier and having a submarine on your tail.

On the 24th, planning to return to the Bay and visit Crisfield, MD for the first time. The “Crab Capital” of the east coast.

Looking for people to join up in Crisfield. Any takers?

Jaybeaux
 
On my way to Montauk Point.
My morning so far
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That was in some good current
Look at my trip total
I was running between 78-82% load as best I could
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dcwjd said:
Looking at your vessel view Zeus doesn’t really make much of a difference in economy or speed over the shaft drive version. I always thought it did and that was a major benefit of having it. 2350 rpm I’m doing the same speed and same gph and same load.
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@dcwjd
You make an interesting point.

How about we all post pictures of our vesselviews while under way, and then describe conditions, load, fuel, water, etc.
 
Ok, this is a timely topic for discussion. We are currently on a trip. Greetings from Norfolk, VA. So I've been running around the Bay for the past 5 days, all sorts of sea states, tides, currents, etc. Don't really give a crap, we just go. I've started to log engine data every hour or so just to keep an eye on things.

So in some "calm-ish" conditions, I decided to do a WOT run. In my mind, I'm looking for 2650 rpms. I have the engines in sync mode, I pin the starboard throttle, and I top out at 2580 rpms. Hmmm? I record the rest of the engine data. Was sitting at 99% load.

So I reached out to some guys here on the board and my first mistake was that I was doing WOT with the trim tabs in the down position. So, I took the tabs back to "flat". I didn't get to do a WOT that day as it was a tad rough and I didn't want to upset the Admiral. However, I did notice that my fuel economy (speed in mph divided by consumption in gph) had improved. I think that I was pushing the bow down too far and plowing water. But here's my confusion:

I understand how that would affect my speed and my miles/gallon, but what I don't get is how (if at all) that would/could affect WOT rpms? The only thing the engine knows or feels is the propeller on the end of the shaft. In my head, the same could be said for a dirty bottom. That will impact speed and fuel economy dragging a carpet around, but shouldn't the engine still be able to spin up to WOT rpm, in my case 2650?

I don't think that I have hit anything so I don't think it's the props. They were just tuned up last year. The boat is due to be pulled for bottom paint, etc after this season. We are primarily a fresh water boat but there are times, like now, that we spend a week or two in the Bay in salt water.

What do you guys think? I should have an opportunity tomorrow to do another WOT test, this time with the tabs all the way UP, and I will not engage the engine synchronizer to see if maybe one engine is holding the other back. I'll report back tomorrow evening.

Jaybeaux
 
@Jaybeaux
Agreed with your tests.
Disengage the synchronizers

With all other conditions equal, with full tabs, I am faster and higher load (burning more fuel for same RPM).
 
Out on the peconic bay this am. Like glass
 

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