Which is more fuel effecient? twin F115s or single 200hp Johnson Ocean Pro? - The Hull Truth

starboard enterprise · 03-08-2007, 03:45 AM

Simple question for you guys. My pops thinking about repowering his 01 Wellcraft 23', it comes with a carbed 200hp ocean pro Johnson. Its a little thirsty with oil/gas, probably averages 1.8-1.9 mpg. He wants to get twin F115 yamaha's, do you guys this gas mileage will improve greatly? With gas hovering around 4 dollars + price of oil, hes using his boat less and less.

tommyr904 · 03-08-2007, 06:37 AM

the cost will not outwiegh the savings.if the old johnson still runs {i assume it does they are great motors} you can buy a ton of fuel with 20k

timebandit · 03-08-2007, 09:23 AM

You can buy a ton of fuel with $20k, and the Johnson is really the better motor. Perhaps a kicker to go with the single. As far a twins getting the better economy, sometimes they do. Depends on the boat and number of other factors, because the engines don't work as hard. If the twins are V-4's like my '82 248 was than probably equal or a little worse than a newer high tech O/B. Although, two new tech F-115's might come out ahead of an older 200 carb 2S.

gman25 · 03-08-2007, 10:28 AM

Quote:

timebandit - 3/8/2007 8:23 AM

and the Johnson is really the better motor.

Did I read this right?? Now a carbd Johnson is better then a Yamaha 4 stroke???Now I heard it all..

2005 300 Grady White Marlin w/F250's

timebandit · 03-08-2007, 10:42 AM

Better than the F-115. I would rather see starboard move up to a single F225 or F250.
115's have a far less than impressive track record over the years.
Twin 150's would be nice.

gman25 · 03-08-2007, 10:54 AM

I think the twin F150's would fit the 23' Wellcraft just right.

jeffro22 · 03-08-2007, 11:17 AM

what about a leftover pair of DF140's. Awesome motor and great on fuel. should be plenty of power and problably the best price you will find

Flot · 03-08-2007, 11:55 AM

Do the math, it'll never come out in your favor if you are really doing it to save money - even if someone gives you a great price for the used carb motor (which is unlikely), you'll be at least $10k in the hole. $10k is 2500 gallons of gas - or 10-15 years of pretty good use for a 23' boat.

A more sensible move cost wise might be to put a single brand new 200-225 on it, and justify it in that you are not only getting a quieter newer more reliable engine but you can get one with a 6 year warranty and as a BONUS you will get twice the fuel economy. But again, you'll be way in the hole financially.

nas130 · 03-08-2007, 01:36 PM

I am not familiar with the boat, but the weight of two four strokes might be much more than a single.

nas

Cracker · 03-08-2007, 02:10 PM

Quote:

timebandit - 3/8/2007 8:23 AM

You can buy a ton of fuel with $20k, and the Johnson is really the better motor. Perhaps a kicker to go with the single. As far a twins getting the better economy, sometimes they do. Depends on the boat and number of other factors, because the engines don't work as hard. If the twins are V-4's like my '82 248 was than probably equal or a little worse than a newer high tech O/B. Although, two new tech F-115's might come out ahead of an older 200 carb 2S.

Wow, While agree their is a big investment over a payed for engine. The F115's are not bad engines as at least you are implying in this post and the other. Most of the problems with the F115 is carbon build up, it just requires use of decarbing agent. The F115's are nice for reliability, but it is a big investment. On my 23 footer which its a 9 foot beam I average about 2.5 MPG to 2.7 doing 28 to 29 MPH. Definitely check how about 800lbs on the back of your boat does...The F115's weigh around 416 LBS. (If my memory is correct).

brazzy · 03-08-2007, 02:18 PM

I believe the point of your question should be performance difference you will see with one engine versus two engines. The biggest factor in favor will be the come home ability in the event of a breakdown. I vote for the single engine. The cost of ownership including the gas will be much less. Two engines sucking gas, even though they individually use less will probably use more than the single older carbed engine. The performance difference will not be a decisive factor, the single engine should be a bit faster. Less Weight Less Drag.

1987 Hydra Sport 25 WA
300 V8 Johnson 51 MPH WOT

I can buy a lot of gas for the amount of money it takes to upgrade.

Cracker · 03-08-2007, 02:33 PM

Quote:

brazzy - 3/8/2007 1:18 PM

I believe the point of your question should be performance difference you will see with one engine versus two engines. The biggest factor in favor will be the come home ability in the event of a breakdown. I vote for the single engine. The cost of ownership including the gas will be much less. Two engines sucking gas, even though they individually use less will probably use more than the single older carbed engine. The performance difference will not be a decisive factor, the single engine should be a bit faster. Less Weight Less Drag.

1987 Hydra Sport 25 WA
300 V8 Johnson 51 MPH WOT

I can buy a lot of gas for the amount of money it takes to upgrade.

I agree with the above. I am a fan of twins but I fish a ways offshore...

rbutterworth · 03-08-2007, 02:38 PM

wait wait WEIGHT a minute.....better check with wellcraft of someone regarding the amount of weight you're about to dump on the transome regarding the 4 strokes...like many have said....20K will buy alot of fuel...it may be hard to justify that even at nuclear war prices...., if you were to repower....go with etecs, or opti's......4 strokes are heavy suckers...especially on an older hull.......

sandy · 03-08-2007, 04:05 PM

The March issue of Powerboat Reports compares two F115s against a single F225 on the same boats. They gave the edge to the single for many of the same reasons give here.

Kid Stuff · 03-08-2007, 05:40 PM

Get a 4 stroke kicker.

solarfry · 03-08-2007, 06:04 PM

Quote:

starboard enterprise - 3/8/2007 2:45 AM

Simple question for you guys. My pops thinking about repowering his 01 Wellcraft 23', it comes with a carbed 200hp ocean pro Johnson. Its a little thirsty with oil/gas, probably averages 1.8-1.9 mpg. He wants to get twin F115 yamaha's, do you guys this gas mileage will improve greatly? With gas hovering around 4 dollars + price of oil, hes using his boat less and less.

You are forgetting boat in question was designed to carry weight of old two strokes. If you hang a pair of 500 # outboards on stern they just might break stern and fall off. 1000# is not same as the 600# of a single. It will destroy trim and create handling problems. Most prominent being porpoising.

Maybe a single etec or hpdi might be a better solution. Don't listen to the twins crowd that much. It's your boat and money.

At 100 - 200 hrs of use you will never recover your investment in your lifetime. It's sorta like buying a diesel to save gas on your truck and only using it 5,000 miles a year or less. A lot of people do that to keep up with Jonesy.

Be advised that the fuel savings at most amount to 30% increase at idle. At running speed it runs around 15% only. Fuel savings are exagerated drastically by the four stroke crowd. I know I went from a 20' with 150 2S (3.5 mpg @ 4k) to a 21 with a F150 (3.9 mg @ 4k). 4 strokes are heavily overrated by the automobile crowd.

I agree with comments below:

Quote:

Do the math, it'll never come out in your favor if you are really doing it to save money - even if someone gives you a great price for the used carb motor (which is unlikely), you'll be at least $10k in the hole. $10k is 2500 gallons of gas - or 10-15 years of pretty good use for a 23' boat.

A more sensible move cost wise might be to put a single brand new 200-225 on it, and justify it in that you are not only getting a quieter newer more reliable engine but you can get one with a 6 year warranty and as a BONUS you will get twice the fuel economy. But again, you'll be way in the hole financially.

solarfry · 03-08-2007, 06:12 PM

Quote:

Kid Stuff - 3/8/2007 4:40 PM

Get a 4 stroke kicker.

Keep your 2 stroke. Maintain it more than once every 18 mos..

phillipj1 · 03-08-2007, 06:16 PM

Quote:

... averages 1.8-1.9 mpg. He wants to get twin F115 yamaha's, do you guys this gas mileage will improve greatly?...

Though some have inferred the answer, I think I missed more than 1 direct answer
which would be Yes, the mileage should be around %30 better. A guy selling a contender 23 with twin 115s claimed 2.5.

Now everyone please continue the philosophical debate.

JP

brazzy · 03-08-2007, 06:41 PM

I disagree with you. the gas consumption would increase. As I stated earlier two engines even though using less individually will still us more than the single carbed engine. It's got nothing to do with weather the engines are 2 cycle or 4.
I used a 22 foot whaler with twin 115 Johnsons in the Bahamas. We replaced the twins with a single 225 V6 Evinrude. The boat would use 1/3 less fuel and had a much higher top speed. These were carbed engines back in 1995, but the results will not be that much different with what he wants to do with his Wellcraft.

Cracker · 03-08-2007, 07:27 PM

Brazzy,
If we are strictly talking about replacing a carbed 200 with two Yamaha F115's, The F115's will get about a .5 mile better per gallon on the mileage. Now if your talking gas consumption difference between an F225 and twin F115's then yes the F115 will use more fuel. I would guess between 20 to 33 percent more fuel...It is just going to depend on what the owner wants.