gas milage

[shlowe]

I,m a new guy to the forum and looking for a little help. I have a 360 Sundancer with 8.1 Horizons and am getting ready to go on a trip with a friend who has a Trawler that cruises at about 8-9 mph. If I go about the same speed, should I shut one engine down or idle both.I'm getting about a half mile per gallon now--- any idea what the MPG would be going that slow.

 

[billnpat]

I,m a new guy to the forum and looking for a little help. I have a 360 Sundancer with 8.1 Horizons and am getting ready to go on a trip with a friend who has a Trawler that cruises at about 8-9 mph. If I go about the same speed, should I shut one engine down or idle both.I'm getting about a half mile per gallon now--- any idea what the MPG would be going that slow.

Not sure about shutting one engine down...wouldn't you go in a circle?? and idling i suppose would be like 1-2 miles an hour...:huh:

Hope someone else has a answer for you :smt001

 

[Summer Fun II]

For getting the best mileage is to run at hull speed. :thumbsup:
I shut down one engine when I'm on the NYS canal the speed limit is only 5 and 10mph with no wake.
Then on the way back I run the other engine to keep the same hours on both engines. :smt001

 

[Sundancer]

Don't forget when you shut one engine down, usually the starboard, you lose your power steering. If you are a weight lifter, no problem!

 

[VinceR]

SEA RAY 340​

2001​

PERFORMANCE​

“WILD RICE”​

TWIN 454 MPI​

​

Speeds by GPS
Fuel Flows by computer connected to engines.

RANGE IS 215 GALLONS

RPM MPH GPH MPG RANGE

700 3.9 2.0 1.95 419

1000 6.0 3.6 1.66 358

1200 6.8 4.4 1.55 333

1500 7.9 7.0 1.13 242

 

[billnpat]

For getting the best mileage is to run at hull speed. :thumbsup:
I shut down one engine when I'm on the NYS canal the speed limit is only 5 and 10mph with no wake.
Then on the way back I run the other engine to keep the same hours on both engines. :smt001

Wayne....i thought that the props turn in different directions :huh: so if one engine was off would that make going straight not happen..HELP :huh::huh:

 

[billnpat]

Don't forget when you shut one engine down, usually the starboard, you lose your power steering. If you are a weight lifter, no problem!

So to help me understand, you would use all your muscle power to keep the boat straight with the steering ???

 

[my3sons]

welcome from another 360 owner!
We traveled the length of the Erie canal last year in ours so I can tell you that in the "dug" portion of the canal where the speed limit is 10 MPH we were getting 1.1 to 1.2 MPG.
We traveled between 7 and 8 MPH because these boats are just moving too much water at 10 to be efficient, and the wake is too much for the shoreline. My smartcraft readings were about 1.4 MPG when actually underway and moving at those speeds.
Have not used one motor, so I am not sure about that idea.
It is common practice for some to use 1 stern drive in the canal and some guys trolling for walleye here run both inboards but only have one transmission engaged for the slow troll they need for the early season. Personally, I wouldn't want the prop shaft wind milling with out the motor running. Just my opinion.

 

[Summer Fun II]

so if one engine was off would that make going straight not happen..HELP

Bill, Going straight is not a problem at 5mph on one engine. :smt001

you would use all your muscle power to keep the boat straight with the steering ???

You don't need power steering when going in a straight line. :grin:

 

[billnpat]

Bill, Going straight is not a problem at 5mph on one engine. :smt001
You don't need power steering when going in a straight line. :grin:

Bill, Going straight is not a problem at 5mph on one engine.
:lol: Thanks, Im learning.....:thumbsup:

 

[Hampton]

I think we are getting the facts out.

I agree with Scott that 9 mph is the upper end beyond which mpg goes down. I have cruised single engine, but not recently. It is more efficient at slow speed, and not too hard to steer at all (docking would be different). Before cruising single engine, make sure you have a prop shaft seal crossover cooling line (line from port to stbd shaft seal - bi-directional - either engine will lubricate both seals.)

If it's so important for you to cruise with the trawler, hopefully, it'll be important enough to him to slow down 1 mph or so - you're economy will go way up.

We will probably cross fom Apalach to Tampa (Hudson, actually) in a couple of months. It's at the upper end of our range. We plan to leave at sunrise and cruise out to deeper water, slow down and fish for several hours - 1 engine at a time, and then cruise in to Hudson before sunset. A great day of fishing and saves an extra 1/2 day of cruising. If you look at a map, we'd have to go NE from Apalach to get gas (Carabelle...) which would increase our trip's distance significantly, since we are trying to go SE. No gas avail in Cedar Key.

http://maps.google.com/?ie=UTF8&ll=29.161756,-83.474121&spn=2.47021,5.009766&t=h&z=8

 

[Sundancer]

You ever tried to keep a twin engine boat straight with only one engine? Yes, you will get a work out! Especially in a narrow passage or dodging traffic. Try it!!

On most of the old DA's from my era, the props do not contra rotate!

 

[Summer Fun II]

Yes, you will get a work out! Especially in a narrow passage or dodging traffic. Try it!!

Well I guess thats not going in a straight line is it !!!. :grin:

If you're going straight why are you fighting with the wheel to stay straight ??
I don't have that problem with my tug on the canal.
If you really need power steering start the other engine. :grin:

 

[Sundancer]

I tried it once so that if I ever HAD to do it, I would know what to expect. I always run both engines and around here, there aren't any places where shutting one down even makes sense.

 

[Two Peas]

According to Boattest.com, you'll get 1.5mpg at 1500rpm and 8.6 mph. If you go to their site and register for free, you'll be able to see all the data with respect to speed, fuel burn, and range for the rpm scale for the 360da.

 

[magster65]

I,m a new guy to the forum and looking for a little help. I have a 360 Sundancer with 8.1 Horizons and am getting ready to go on a trip with a friend who has a Trawler that cruises at about 8-9 mph. If I go about the same speed, should I shut one engine down or idle both.I'm getting about a half mile per gallon now--- any idea what the MPG would be going that slow.

There's no easy answer. Trawlers and planing hulls are totally different boats. The way I see it is you have 3 choices;
1. Get the trawler guy to go your best slow speed.
2. Get him to tow you and drink all his beer for entertainment.
3. Just cruise your 28 mph and then stop and meet him every so often. That'd be... cruise for an hour and a half then wait for 4 hours while he catches up.

 

[billnpat]

There's no easy answer. Trawlers and planing hulls are totally different boats. The way I see it is you have 3 choices;
1. Get the trawler guy to go your best slow speed.
2. Get him to tow you and drink all his beer for entertainment.
3. Just cruise your 28 mph and then stop and meet him every so often. That'd be... cruise for an hour and a half then wait for 4 hours while he catches up.

QUOTE:
Just cruise your 28 mph and then stop and meet him every so often. That'd be... cruise for an hour and a half then wait for 4 hours while he catches up.

I LIKE THAT IDEA BEST....:thumbsup::thumbsup::thumbsup:

 

[Four Suns]

The bigger boats have an additional booster, (if they are lucky) but it too is stand alone, not connected to the engines in any way shape or form.

Depends on what you mean by "bigger boats." My primary hydraulic pump for the steering is on the PTO of the starboard transmission and is not a stand alone pump. If I lose the starboard engine, I essentially lose the ability to steer the boat in a meaningful way.

 

[tdappleman]

I've had to run on one engine due to mechanical problems not by choice. It isn't a fun trip - the boat does wander and if I'm running on the port engine I have no power steering. Cruising mine at 8mph means running at about 3500rpm when I normally cruise at 3200rpm. Not fun.

 

[Redhook98]

It's easy to stay in a straight line with one motor with an Autohelm! And with the remote, you can even sit on the bow and dodge bouys and other traffic. (I don't recommend the bow part, but it is a fun party trick with guests on board).