|
|
Member
Posts: 1656
| I'm not arguing fuel economy. The topic is fuel consumed. Fuel consumption is lower in rough water than it would be in calm water. You simply can't go WOT.
Waves? NOAA 2'ers are not run wide open waves. I'll gladly take Steve and/or TJ out on Central or upper Green Bay or Lake MI in 2-4' NOAA wave forcast. It's not a comfy boat ride. |
|
| |
|
| http://www.hotribs.com/03press/241-suzuki/suzuki.asp
|
|
| |
|
Member
Posts: 3899
| So answer my question. What is considered rough? 2-4 footers, when you can run a steady speed? Or above that, when you have to be on and off the throttle?
Again, I can get better economy and use less fuel if I maintain steady speed in rougher than calm conditions, when I can't go WOT for not wanting to beat the boat up. I get poorer economy if I have to be on and off the throttle continually. Consumption for me is less in those conditions, because I'm probably not traveling as far to those fish.
I think we're arguing semantics here.
Edited by Shep 2/26/2008 10:12 AM
|
|
| |
|
Member
Posts: 1656
| I guess there in lies the question, What is rough? Green Bay NOAA forcast 2-4's. I'd call rough, very rough. NOAA 1-3's can be a very bumpy day. Calm to 2' forcast is what you need to run wide open as long as waves are 1' or less. I'm speaking about waves not chop. |
|
| |
|
Member
Posts: 1382
| OK, I'm going to run 30 miles one way on Green Bay at WOT - flat calm. Get there and fish all day.
On the way back wind has kicked up its nasty and now I'm averaging 20 -22 mph on the way back. Whatever the RPM's are (I don't know, too busy trying to read the GPS as well as the next wave), but let's say its highly variable, under great load, the prop is less inefficient and occasionally cavitates and the prop vents aren't completely closed off and beyond that it takes me three times as long to get back. Let's say the avg RPM is a loaded 3500-4000.
30 minutes at 5600 rpm vs 90 minutes at a loaded 3750. Which one burned more fuel? |
|
| |
|
Member
Posts: 617
Location: Oshkosh, Wisconsin | Not trying to be a pain, but....
Physics... if your leaving Cedar River and traveling a straight line distance to your fishing spot 34 miles away at WOT and your engine gets 2.5 mpg at WOT, your total fuel consumption is 13.5 gallons. Now assume its "rough". The waves are following a perfect sine wave (the track along the top of the wave is 50% longer than the wavelength). Instead of traveling 34 miles, your boat now travels 51 miles (roughly). Your fuel efficiency at reduced rpm's should be pretty close to 4 mpg, thereby reducing you fuel consumption to 12.8 gallons.
I haven't been in a "pro's" boat, but I have fished GB a fair amount. IMHO, any increase fuel consumption on "rough" days is from guys running miles out of their way trying to find the smoothest (and therefore fastest) path to their spot. I don't believe feathering the throttle is something that most people do a lot of on LONG trips because its simply too hard to maintain the focus necessary on both keep your speed as fast as you can AND still avoid breaking a lot of equipment. Those people willing to run their equipment at the ragged edge of what conditions will allow obviously have made the decision that they are willing to chance breaking something, so I doubt fuel consumption is that big of a consideration.
Interesting discussion either way. |
|
| |
|
Member
Posts: 617
Location: Oshkosh, Wisconsin | I was working on my last response before WF posted his. |
|
| |
|
Location: Rhinelander | Another consideration many are missing is the fact that under load as in driving a boat in rough seas, the injectors are supplying more fuel to HOLD the engine at 3500 RPM. 3500 in calm seas with the boat on plane gives the 'average' rating mentioned. That's similar to EPA fuel consumption ratings on a truck...drive that truck uphill and those injectors have to go to work supplying enough fuel to hold the truck at the desired speed, slow OR fast, going uphill. Anyone who drives in the mountains will tell you you use more fuel climbing hills, than on a flat road, even if the hill going up and going down are exactly the same, which in most cases isn't true on the water.
My Toyota Tundra has a fuel mileage meter that can run full time. 2000 RPM going up hill (until the tranny shifts down and RPMs go up)will get me about 10 MPG, while 2000 RPM on a flat road surface gets me about 19.
Every time one hits a trough, the boat slows considerably, and the engine has to work to gain back the lost momentum to climb the next wave. I listen to NOAA too, and know exactly what a 2' to 4' sea can look like...the 4' part is where you will really see the effect of what I'm trying to say.
From the article posted above:
The inventors of the Challenge have devised a points system relating to fuel
consumption, so it is not necessarily the fastest boat that will take the
title. Matthew Sillifant explained, 'these days everyone is much more aware not only of fuel costs but also the impact on the environment and this is particularly true in the commercial maritime sector'.
Matthew Sillifant record time included 3 re-fuelling stops whilst achieving the 540-mile record voyage, using 1290 litres of fuel. The bad weather and rough sea state play its part by increasing fuel consumption as the outboards had to continually to accelerate and de-accelerate as they battled though the steep seas which had not been forecasted....
|
|
| |
|
| there will be a point where the lines will cross and rough water running will be less economical based upon roughness of the water, would be interesting to do an actual test sometime. Maybe it could be tested with icpmmand or smartcraft? I would guess it would be the point at which you were no longer really able to get fully on plane.
|
|
| |
|
| icommand, oops
Last post done from iPhone, sorry to rub it in Steve... |
|
| |
|
Member
Posts: 617
Location: Oshkosh, Wisconsin | Steve -
There are MANY items to consider when talking about fuel efficiency. My boat was more efficient in rough water than it was in flat conditions at WOT. My pocket book verified that for me quite conclusively.
Perhaps other people boats are different. I KNOW my boat used less fuel making the same trip in rough seas as compared to flat seas at WOT because I checked. The gas pump does not lie. |
|
| |
|
Member
Posts: 1656
| Well let's throw another variable into the whole mix. Are we talking Suzukis' or High end E-tecs?  Motor considerations
When fishing the MWC out of Linwood on Saginaw a few years back. I ran a Javelin 21 MSX with an F225 and our team mates ran a Crestliner 202 with and Opti 225. same HP different makes and different boats. We ran 40 miles as the crow flies to the Steeples, when we left we could run WOT by time we got to the spark plug we were probably down to about 1/2-3/4 throttle and by time we reached the Charities we running into left over energy from the thrusday blow and hitting big rollers at which point we were driving up and down waves. The run back in was between 3/4 and WOT because waves had laid down. The difference in burned fuel between the two boats was about 8 gallons, same trip same spots. The Merc drank more.
"Every time one hits a trough, the boat slows considerably, and the engine has to work to gain back the lost momentum to climb the next wave."
Here's where driving habits can have a drastic effect too. When I'm in the "big" stuff. I will drive my boat to maintain momentum, this is done usually by watching the RPM's and adjusting the throttle accordingly. I also quarter waves to minimze hitting "breakers" and help maintain my momentum. |
|
| |
|
Location: Rhinelander | Matthew Sillifant record time included 3 re-fuelling stops whilst achieving the 540-mile record voyage, using 1290 litres of fuel. The bad weather and rough sea state play its part by increasing fuel consumption as the outboards had to continually to accelerate and de-accelerate as they battled though the steep seas which had not been forecasted....
In my case, I also checked and not just a couple times. I use more fuel in rough water. So did the guys in this article, and they were TRYING NOT to in order to set a record. So this proves out that the operator intent and desire has everything to do with results on fuel economy in rough AND calm seas, again pointing out we are largely debating semantics.
As far as Merc VS E Tec, here you go:
Merc 225 Pro XS MPG 6.2
Yammy VMAX HPDI 5.8
ETec 225 HO 5.0
Not according to Merc, either, this was a test done by Bass and Walleye Boats.
|
|
| |
|
Member
Posts: 1656
| You're right, I completely made up the Saginaw trip.
again, my experiences...but hey who know's maybe I live in fantasy land. |
|
| |
|
Member
Posts: 1382
| Yes, and the type and shape of the wave will have an extreme effect on what the results are. Are they tall steep waves close together or are they big swells can you essentially quarter and run on plane? That I can see. All good points. When I think rough water I generally think of heading into the steep, close-together variety you find on Green Bay and its Bays. |
|
| |
|
Location: Rhinelander | You ran a Javelin, your teammates ran a Crestliner.
there's your sign...
Different rigs. probably different propping. Lots of variables. |
|
| |
|
Member
Posts: 3899
| Shouldn't this thread be in the Walleye Boats and Motors Forum?
As for that F225 Yamaha using less fuel? I can believe that, because I'm sure it was going much slower than the Merc Opti!
Edited by Shep 2/26/2008 12:01 PM
|
|
| |
|
Location: Rhinelander | Shep, you kill me. |
|
| |
|
Member
Posts: 2445
Location: Fremont, Wisconsin | Wow, thats all I gotta say about this thread.
|
|
| |
|
Member
Posts: 1656
| "same HP different makes and different boats." I believe I stated that? Damn, I must be a hell of a lot dumber than I look
This debate has become pointless. There is no value on people's experiences and real world situations vs opinoins. It's no surprise why other veteran fishemen shy away from commenting on this website. I'm beginning to understand why more and more veteran fishermen don't want to deal with the headaches of these internet forums. |
|
| |
|
| I don't see anything wrong with arguing a valid point, don't take it too personally, just as I won't take your comment above personally. It's just a discussion. |
|
| |
|
Member
Posts: 1040
Location: Stevens Point, WI | wf - 2/26/2008 12:53 PM
I don't see anything wrong with arguing a valid point, don't take it too personally, just as I won't take your comment above personally. It's just a discussion.
You couldn't have said it any better! |
|
| |
|
Location: Rhinelander | 'There is no value on people's experiences and real world situations vs opinoins.'
Disagreeing doesn't indicate disrespect. I suppose we all could add the phrase 'With all due respect'
"same HP different makes and different boats." I believe I stated that? Damn, I must be a hell of a lot dumber than I look
I took the post to mean the Mercury was less fuel efficient than the Yamaha, and by 8 gallons. I thought it should be pointed out that the boat might have something to do with that and that the Opti has the best fuel economy rating out of the three listed in my post, including the 'high end ETEC', so I did. I fail to see the problem with that, no disrespect was intended at all. |
|
| |
|
| Maybe this needs to be considered...
Does stained water create more friction on a boat's hull that would give it worse gas mileage in stained lakes than on clear lakes? |
|
| |
|
Member
Posts: 2300
Location: Berlin | At this point all I can say is I agree with EVERYONE! This has been some thread. Takes me back a few years to the old days where the recycle bin got a good workout. I bet if you looked, most of the posts in the recycle bin were started in February?! Gotta have these once in a while to appreciate the open water season. Personally, I think my winter "period" is almost over and I am sure glad I only get one once a year and not every month.
Lets all get together, get sloppy drunk throw in a group hug or two and discuss gas consumption. This of course after a long day on the water pounding big eyes out of Denny's Tuffy. |
|
| |
