Official 280 Sundancer Thread

Hi everybody,

I'm new to this thread and looking for some help diagnosing an issue. Late last season I was struck by lightening. Seem finally to be back on track after having to replace 100% of my electrical system. (Thank God for insurance!)... except for one thing:

In prior seasons I was able to hit max speeds of 40-45mph on my twin 2004 Bravo 5s. This year I'm maxing at 25-27mph in similar flat conditions. I am also noticing that from 2/3 to full-throttle there is zero increase in RPM or speed. I am maxing about about 4100RPM.

The only other item I need to share is that this season my in-dash speedo is not operating due to a clog in the I/O. When I referred to speeds in past seasons it was from the in-dash speedo. Whereas this year I am getting my speed reading from my Raymarine C80 GPS. In prior seasons I never bothered to compare the GPS speed to the in-dash speedo... so I'm not sure how closely they track to one another.

Does anybody have any insight to share? Trying to determine if this is (should be) part of my lightening strike repair punchlist...

Thanks in advance.
 
Has anyone ever removed the SR emblem on the transom hatch. I want to put a name across the transom but that thing is in the way. I have noticed after the 01-02 years they didn't put them on there. If you have removed them, what did you use? did it leave a mark or discoloration? Thanks.
 
finsup said:
Hi everybody,

I'm new to this thread and looking for some help diagnosing an issue. Late last season I was struck by lightening. Seem finally to be back on track after having to replace 100% of my electrical system. (Thank God for insurance!)... except for one thing:

In prior seasons I was able to hit max speeds of 40-45mph on my twin 2004 Bravo 5s. This year I'm maxing at 25-27mph in similar flat conditions. I am also noticing that from 2/3 to full-throttle there is zero increase in RPM or speed. I am maxing about about 4100RPM.

The only other item I need to share is that this season my in-dash speedo is not operating due to a clog in the I/O. When I referred to speeds in past seasons it was from the in-dash speedo. Whereas this year I am getting my speed reading from my Raymarine C80 GPS. In prior seasons I never bothered to compare the GPS speed to the in-dash speedo... so I'm not sure how closely they track to one another.

Does anybody have any insight to share? Trying to determine if this is (should be) part of my lightening strike repair punchlist...

Thanks in advance.
Click to expand...

You are comparing the GPS' Speed Over Ground against the speedo that measures speed through the water. The difference can be significant. Follow this simple illustration;

For illustration purposes lets assume that in calm motionless water with no wind, 3500 rpm results in a speed of 20 knots. In this case the SOG would equal speed through the water, 20 knots.

If you take that boat and run it upstream in a current going 5 knots (against you) the SOG would be 15 knots (20-5), and speedo would read 25 knots. If you were going downstream with the current SOG would be 25 knots and speedo would read 15.

Cross currents and wind have the same effect, although not as obvious because as they push the boat to side, and then the analysis gets bogged down in vectors and trigonometry.

For a better understanding, and some very useful information, you might consider taking one of the USCG approved basic navigation courses during the winter. Besides the obvious navigation knowledge, it can help you learn to operate your boat so that it is more fuel efficient.

Henry
 
Can you put your boat setup and location in your signature, you'll get better help that way.
 
finsup said:
Hi everybody,

I'm new to this thread and looking for some help diagnosing an issue. Late last season I was struck by lightening. Seem finally to be back on track after having to replace 100% of my electrical system. (Thank God for insurance!)... except for one thing:

In prior seasons I was able to hit max speeds of 40-45mph on my twin 2004 Bravo 5s. This year I'm maxing at 25-27mph in similar flat conditions. I am also noticing that from 2/3 to full-throttle there is zero increase in RPM or speed. I am maxing about about 4100RPM.

The only other item I need to share is that this season my in-dash speedo is not operating due to a clog in the I/O. When I referred to speeds in past seasons it was from the in-dash speedo. Whereas this year I am getting my speed reading from my Raymarine C80 GPS. In prior seasons I never bothered to compare the GPS speed to the in-dash speedo... so I'm not sure how closely they track to one another.

Does anybody have any insight to share? Trying to determine if this is (should be) part of my lightening strike repair punchlist...

Thanks in advance.
Click to expand...



Smartcraft has you in guardian mode and its limiting your engines maximum output. Its an electrical issue.

Have someone connect a diagnostic code reader.
 
Where can one find the swivel type mount that would work in the cabinets?

gerryb said:
The LCD upgrade is a no brainer if you have the model years with the crt tv in the cabinet. We went to a DVD/LCD made by Sharp. Much nicer and give us a whole cabinet for storage. I initially purchased a 15" AC/DC but returned it as I wanted to biggest that could fit in front of the starboard cabinet without sticking out over the edge. Swivel mount on the front-port side corner of the cabinet where theres a nice piece of wood to hold the mount. The Sharp is a AC only but we have a converter when needed.
Click to expand...
 
Finsup:

No question your speedo and GPS SOG could be very different. My speedo is MPH, not knots...but my GPS is knots. Between the SOG vs. pitot difference and the MPH vs. knots difference, you could see very different speeds. Are your tachs up around 4k rpm WOT? If so, it does not sound like an electrical issue to me.
 
bport said:
Finsup:

No question your speedo and GPS SOG could be very different. My speedo is MPH, not knots...but my GPS is knots. Between the SOG vs. pitot difference and the MPH vs. knots difference, you could see very different speeds. Are your tachs up around 4k rpm WOT? If so, it does not sound like an electrical issue to me.
Click to expand...


Hi bport,

Are you talking about wide open (WOT) tach readings?

At WOT my tachs are at about 5,050 to 5,100 RPM each. Normally this is about 47-48 MPH per the GPS.


Come to think of it, 4,100 RPM’s at 27 MPH seems like a lot of RPM’s
We often cruise around 27-28 MPH. I think the tach’s are close to 3,300 RPM at this speed (ballpark estimate from memory)
 
Last edited:
Presentation and Finsup:

I am not a mechanic - so I defer to the professionals on the board. That said, if you are still getting the same RPM you have been at wide open throttle, I can't see how it could be electrical or the result of lightning.

Presentation, you are cooking at 47-48mph. Now I have a challenge for this weekend.
 
bport said:
Presentation and Finsup:

I am not a mechanic - so I defer to the professionals on the board. That said, if you are still getting the same RPM you have been at wide open throttle, I can't see how it could be electrical or the result of lightning.

Presentation, you are cooking at 47-48mph. Now I have a challenge for this weekend.
Click to expand...

bp, I have no bottom paint. In the photo above it looks like you do have bottom paint.

I dont know how much top end speed that costs but that may make a difference.
 
OK Presentation now you are rubbing it in. I have little Christmas trees growing off my outdrives by this point in the season. Enjoy all that fresh water.
 
bport said:
OK Presentation now you are rubbing it in. I have little Christmas trees growing off my outdrives by this point in the season. Enjoy all that fresh water.
Click to expand...

Try your speed run in spring right after you launch when the hull, drives and propellers are clean and the cabinets are not yet stuffed to the max.
 
496 MAG Coolant a little low - any thoughts?

I was down in the engine compartment today and noticed the coolant was a little low. It was topped off about 1 month ago and I notice now that its a little low. I couldn't see any signs of it in the bilge - any idea where it would be going?

The 496 MAG is a closed cooling system.

The boat always seems to run at 170F once the engine is warmed up...
 
Re: 496 MAG Coolant a little low - any thoughts?

trdehmer said:
I was down in the engine compartment today and noticed the coolant was a little low. It was topped off about 1 month ago and I notice now that its a little low. I couldn't see any signs of it in the bilge - any idea where it would be going?

The 496 MAG is a closed cooling system.

The boat always seems to run at 170F once the engine is warmed up...
Click to expand...


Is the motor oil milky looking?
 
How many hours on the engine. What type of maintenence have you had done on the engines. Do you smell it in the bilge?
Could be a failing head gasket also.
 
Re: 496 MAG Coolant a little low - any thoughts?

I checked the oil via the dipstick and no, not milky looking. That was the first thing I checked.

I toped the coolant off yesterday and went for a 2 hour cruise, after the engine cooled off the coolant level was the same...

RiverRat said:
Is the motor oil milky looking?
Click to expand...
 
There is now 233 hours on it. I got the boat about a month ago with 225 on it. Only maintenence I know about is an oil change about a month ago. The mechanic said he topped the coolant off at that time and couldn't find anything wrong with the engine at all. He changed the oil and I would hope would have noted the oil being milky at that time if there was an issue - because this was the check I wanted done before sealing the deal on the boat.

No sent of burning oil or coolant in the bilge.

The only thing I noticed was some oil puddling on top of the engine mount (there is sort of a cup where its bolted down that the oil collected in) on the port side of the boat. That could have been from the previous oil change......I cleaned it up and will be keeping an eye on it.



66pony said:
How many hours on the engine. What type of maintenence have you had done on the engines. Do you smell it in the bilge?
Could be a failing head gasket also.
Click to expand...
 
Does anybody use a (bow) sunpad on their 280? I'd like to get one for my wife but needless to say, it would be right in the way of walking to the anchor.
Also, how would it stay in place?
Or should I forget it....
 
rhodyboater said:
Does anybody use a (bow) sunpad on their 280? I'd like to get one for my wife but needless to say, it would be right in the way of walking to the anchor.
Also, how would it stay in place?
Or should I forget it....
Click to expand...
We use 2 roll up camping cushions that you would lay under a sleeping bag. $10 at Walmart
 
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