gas consumption v4 vs v6

[bob johnson]

So this past sunday my reliable and faithfull( mostly) ocean runner 115 bought the farm.... it might have been my fault and it might have just been its time... I am sure a rod let go and seized the block... It was running so well...I was at WOT...temps were about 130 in both heads and water pressure was 25 PSI!! and she sounded nice. but I just sat at wot for 15 minutes trying to make my way back to the ramp on the glass smooth lake..... and it just started clunking.... eventually after two restarts it seized totally and locked the starter.

sooo I am motor hunting... and found a fast strike 150... its only about 50 lbs heiver than my 115... so I am thinking of buying it, but my one concern is how much more fuel it will use. I have a 175 fast strike on big starcraft, but have only taken it out twice so far... so I don't know the fuel consumption, plus its a different hull.

since this boat is mostly a duck boat and right now it only has two 9 gallon tanks which has served me well with the 115. I have run almost dry a few times though, so I am concerned how much more fuel the 150 will use in like use compared to the 115.....both motors being 60 degree looper OIS johnsons


thanks

bob

 

[flyingscott]

What is your boat rated for if it is rated for the 150 you will need more gas in the boat. If you almost ran out with the 115 you will run out with the 150

 

[bob johnson]

What is your boat rated for if it is rated for the 150 you will need more gas in the boat. If you almost ran out with the 115 you will run out with the 150

the new boats sometimes came with 150's from the dealer....so I am thinking 150 hp for sure.... I still need to figure how much more gas.... I am doing a make over this summer and I have the option of a permanent tank under the floor, or a pair of larger tanks where the 9 gallon units are....but I aslo don't want to use a certain amount of gas just to go duck hunting...if I end up using20 gallons on half the trips.. and at least 15 gallons every trip...I might be too much for what I want to spend... its like pulling teeth to get the hunting buddies to kick in for expenses!!!!!!!!!!!!! 25 gallons of gas...plus the 2 stroke oil, plus the stabil, just for fuel!!!!!!!!!


so anyone have an idea how much MORE gas the v6 might use compared to the V4?

bob

 

[flyingscott]

Rule of thumb is at wide open throttle 1 gallon per 10 hp per Hr

115= 11.5 GPH
150= 15 GPH

 

[82rude]

Tell your so called hunting buddies theres no charge for going out hunting.Now when your out there tell them theres a 30 buck charge for getting back or swim.

 

[bob johnson]

Rule of thumb is at wide open throttle 1 gallon per 10 hp per Hr

115= 11.5 GPH
150= 15 GPH

thanks


so to narrow that down, is there a mid rpm GPH scale?

the reason I ask is during duck hunting season the weather is seldom calm enough to run WOT... those are nice days when its flat...but it just doesn't happen much... when the chop is a foot or more nobody want to go 30 MPH in a 12 degree hull!!!

bob

 

[flyingscott]

No there is no mid range scale your mileage depends on type of boat, the load, the weather lot of things. All i can guarantee is that 6 cylinders use more gas than 4 cylnders. Sounds like your friends like the free ride if you want to maximize your gas mileage lighten the boat up no more dead weight.

 

[bob johnson]

No there is no mid range scale your mileage depends on type of boat, the load, the weather lot of things. All i can guarantee is that 6 cylinders use more gas than 4 cylnders. Sounds like your friends like the free ride if you want to maximize your gas mileage lighten the boat up no more dead weight.

its true....but who wants to go duck hunting alone on the ocean. The killer is the gas is such a small part of how much the boat owner has to pay to be able to go...trailering, getting up early to make sure all is ready, buying the boat and trailer, maintaining the boat, motor and trailer, registering the boat and trailer!, repairing broken and worn parts, and DRIVING to and from...not getting picked up along the way... then when I ask for gas money, I get to SPLIT IT WITH THEM!!!..... as if!!

ususally they seem to just figure out how much gas was used and split it by how many bodies where in the boat...and I get short changed for the oil, and stabil....

truly I need to find another buddy who has his own boat.... to take turns whos we use


bob

 

[sutor623]

I have a TON of friends that like to go striper fishing with me. I also have the same friends that like to go out in my electric only jon boat (there is a 12 acre lake behind my house, along with many other lakes/ponds nearby.)

Some of my friends have more money than the others. The ones that throw money down end up getting invited on the striper rig more often. Wonder why that is?

 

[sutor623]

Back on track..... When I was looking for trucks I looked at the v6 full size (1/2 ton) the small v8 full size, and the large v8 full size. MPG for the v6 were 1mpg better than the v8. The big and small v8 BOTH had the same MPG. Needless to say I got the biggest engine that I could.

What I learned there was that its more the load you are pushing than the engine pushing it. I have heard from a few friends that their v6 (same model truck as mine) actually got WORSE MPG while towing than I do.

Anyways, that being said, if you keep the boat at the same cruise speed with the bigger engine, your rpms should be lower. I think that the difference in fuel usage at CRUISE will be minimal. The issue is, if you can run faster at open throttle with the 150, then naturally you will, soaking up more MPG Just like you ran the 115 at WOT for 15 minutes, I wouldnt put it past you to run the 150 at WOT.

I say DO IT!!!!

 

[flyingscott]

One trick I used is I get my gas on the way hunting, tank is always empty split the cost right there between them. When I needed oil I called one of them to pick it up and same thing with spark plugs and gear lube and other assorted supplies.They split the cost between them when they get to my house. As far as I am concerned the house never pays if they don't like it they can get there own boat.

 

[jimmbo]

One trick I used is I get my gas on the way hunting, tank is always empty split the cost right there between them. When I needed oil I called one of them to pick it up and same thing with spark plugs and gear lube and other assorted supplies.They split the cost between them when they get to my house. As far as I am concerned the house never pays if they don't like it they can get there own boat.

I hope you have Commercial Insurance on your boat, because you just invalidated your pleasure craft insurance

 

[jimmbo]

To the OP
Mr. Johnson. if you were running the 115 wide open, you may actually find the 150 burning less gas cruising at the same speed. The best thing is how it will get on it's hind legs faster

 

[flyingscott]

I hope you have Commercial Insurance on your boat, because you just invalidated your pleasure craft insurance

I do not even know what to say about that. I call shenanigans on you jimmbo are you the guy who wants to ride for free.

seriously though unless your boat was seriously underpowered by the 115. That is probably the only way the 150 gets measurably better gas mileage not something you can count on. If the motor is a good deal and you can keep it out of the throttle it is a really great motor with excellent reliability and reasonably good fuel mileage.

 

[jimmbo]

Read you policy very carefully. Using your boat and receiving Compensation, in any form, may be considered commercial usage by the underwriter

 

[dingbat]

I hope you have Commercial Insurance on your boat, because you just invalidated your pleasure craft insurance

That is incorrect......

On December 20, 1993 the President signed the Passenger Vessel Safety Act of 1993 (public law 103-206), changing the legal requirements for passenger and charter operations. The new law has relaxed the prior strict treatment of situations were a guest provided food or chipped in for expenses. Previous law treated such such guests as passengers, requiring operator licenses and possibly vessel inspection.
Under the new law a passenger for hire is is a passenger for whom consideration is contributed as a condition of carriage on the vessel, whether directly or indirectly flowing to the owner, charterer, agent or any other persons having an interest in the vessel.
Consideration is an economic benefit, inducement, right or profit including pecuniary payment accruing to an individual, person, or entity, but not including a voluntary sharing of the actual expenses of the voyage by monetary contribution or donation of fuel, food, beverage or other supplies.

 

[emdsapmgr]

Jimbo has a valid point. Take an example. Two identical boats, one with a 60 degree V4 115, the other a 60 degree V6 150. If you start off from a dead start and push the both throttles to WOT, both boats may take off close to each other. After a 30 seconds or so, the V6 will slowly start to pull away from the 115, will keep moving ahead of the 115 on an increasing basis. The point is that if you pull the throttle back on the 150, so that it exactly matches the speed of the 115, it could well use less fuel. So, as the 115 would be at WOT, the 150 would be in a mid-speed cruise mode. So, you don't need to run the 150 at WOT, but it's nice to know you have the extra power, should you ever need to get off the lake quickly ahead of bad weather. Both of these 60 degree engines are solid and considered more economical (and have more torque) that the old Crossflows that they replaced.

 

[jimmbo]

I would say the 150 will be ahead from the get go, more torque and it will leave the 115 in it's wake

 

[jimmbo]

That is incorrect......

Ok, I stand corrected. I forgot the laws could be different in the US

 

[bob johnson]

I think I am going to go for the 150.... the theories make sense.....in winter when the winds kick up, having the power to get up and force your way in and ahead of the rough seas is important. I thought I had that...because the 115 is a lot of power as it is. the boat is 20.5' long originally and is 72 " wide at the chine and 8 feet wide at the beam.... but I added 2 ' long flotation pods to the back.... the cost of the motor I have in mind is about the same as if I could find a 115!! $2700....

the dealer has not received it yet in on trade...that happens next week..... while I did worry a little about the gas consumption, I think you guys have eased my mind... the other concern was the extra weight on the transom while I trailer down the road!!.....but its only 50 lbs.... I could have that on the back and more if I mounted my kicker motor!!!!!!!!!!!

I had planned to remove the center console this summer and make the boat a side console, while I tore the floor up to replace the water logged foam.... I think ill just weld in some heavy duty transom braces to ease my mind about the extra weight...( which is going to be hanging off the back of a 10" setback jackplate...

I had always heard that running WOT was extra bad on gas mileage...that's one reason I didn't usually do it....but the motor was sounding so good and I didn't care about the extra gas on a small 15 minute run.... I think from now on ill just stay short of WOT at all times....

bob