Fuel Burn Rate???

[TheKid]

Hey guys, I'm trying to make a guestamant as to what my range would be in the sled.

I have the 222 FF with a Tohatsu 140 2stroke and an 85gal tank. Considering 3 guys and 100lbs ice and gear what do you think I could get.

I've tried to work out numbers but keep getting jumbled up.

What I really need is a flow sensor to get a true reading.

I'm thinking maybe someone has/had a similar boat/motor and can give me an idea.

Normally, salmon fishing 8-10miles out trolling 6-7mph for 7-8 hours I burn 20-30 gallons.

That make sense?

Reason I ask is the tuna are here 30-40 miles out and I'm wondering how long I could stay out for and be safe.

[pete]

fuel safety rule of thumb:use one third out,one third back,one third in reserve.when going out trolling in my boat I alway go to the furthest point away first,and work my way back to my inlet,no backtracking.saves fuel and makes for a shorter ride home. I would love to go salmon fishing,someday!

[fitz73222]

Unless something is wrong, a carburated two stroke outboard wont burn more than 10% of its rated horsepower in gallons per hour at full throttle. 140 hp= 14 gallons per hour. This formula holds very true and has stood the test of time. You are a little light on horsepower for a 22-2FF so I'm going to say you need a good 4400 rpm to get to about 26- 27 mph. If your motor is propped right, you should be turning around 5500 WOT. So if the math holds you should be burning around 11.2 gph at cruise. 7.5 hours of burn @85 gallons or about 197 mile range. So you want to have 30% reserve for your average trip or 28 gallons when you pull her into the ramp. So 56 gallons for your trip will give you a safe, usable range of 130 miles with a safe reserve. Sounds like no problem for your Tuna run. Once you get a flow scan and a GPS you can have very predictable trips for your fuel burn. Of course running offshore is not like flat water running, hence the 30% reserve factor.

[pete]

wow fitz,great info!can't make it any simpler than that.How does the formula work for a fuel injected 2 stroke,like an OX 66?

[fitz73222]

wow fitz,great info!can't make it any simpler than that.How does the formula work for a fuel injected 2 stroke,like an OX 66?

Fuel injected outboards are more effcient than carburated outboards and because on many fuel injected engines the timing curve is controlled either electronically or just more precisely its hard to understand it without a GPS and Flowscan. If you use the carburated engine formula you are always going to come out better with an EFI engine. My best guess is 15% better than a carburated engine. DFI and fourstrokes are advertised at 30% more efficient under the same conditions.

[flounderpounder225]

wow fitz,great info!can't make it any simpler than that.How does the formula work for a fuel injected 2 stroke,like an OX 66?

Pete,
I think I remember seeing 18 or 19 GPH on the Yamaha Fuel Management Guage at WOT on my 250 HPDI, 5400 RPM.  So that is considerably less than the 10% rule for a carb'd motor, and that rule is dead on.  My 96 225 Yami SWS, carb'd motor on the Chris Craft would burn 22.5 - 23 GPH on the FMG.  Fitz, your spot on... 18 or so is 30% better than 25 GPH for a carb'd 250.  Very Interesting
Marc

[Curious]

TheKid-  What are your miles per hour at cruise and WOT with that 140?

I was trying to figure out if a 150 would be enough horsepower for a 222FF.  I'm sure most on this site would say it would be a little underpowered, but I just need to cruise at 24-26 MPH.  My question is, would it be more fuel efficient to run a 150 at slightly higher RPM's or a 200 with the throttle pulled back a little.  My initial guess would be the 150 would be more efficient.  I currently have a Yamaha 200 Salt Water Series carbed motor that I plan to mount but I'm scared of the fuel consumption.  When I got the boat it had an old Evinrude 150 on it and I heard it ran pretty good with that motor before it seized up.  Its a 75 22-2 FF.

[flounderpounder225]

TheKid-  What are your miles per hour at cruise and WOT with that 140?

I was trying to figure out if a 150 would be enough horsepower for a 222FF.  I'm sure most on this site would say it would be a little underpowered, but I just need to cruise at 24-26 MPH.  My question is, would it be more fuel efficient to run a 150 at slightly higher RPM's or a 200 with the throttle pulled back a little.  My initial guess would be the 150 would be more efficient.  I currently have a Yamaha 200 Salt Water Series carbed motor that I plan to mount but I'm scared of the fuel consumption.  When I got the boat it had an old Evinrude 150 on it and I heard it ran pretty good with that motor before it seized up.  Its a 75 22-2 FF.

My 96 225 SWS was the best carb'd motor I ever had, and the fuel burn was not bad, what year is your 200?  I would go with the 200, you pull the throttles back for cruise, and you will get excellent mileage, plus you'll have the power and speed if yoiu ever need it, with the 150, you will always be in the upper RPM range.

[Aswaff400]

TheKid-  What are your miles per hour at cruise and WOT with that 140?

I was trying to figure out if a 150 would be enough horsepower for a 222FF.  I'm sure most on this site would say it would be a little underpowered, but I just need to cruise at 24-26 MPH.  My question is, would it be more fuel efficient to run a 150 at slightly higher RPM's or a 200 with the throttle pulled back a little.  My initial guess would be the 150 would be more efficient.  I currently have a Yamaha 200 Salt Water Series carbed motor that I plan to mount but I'm scared of the fuel consumption.  When I got the boat it had an old Evinrude 150 on it and I heard it ran pretty good with that motor before it seized up.  Its a 75 22-2 FF.

My 96 225 SWS was the best carb'd motor I ever had, and the fuel burn was not bad, what year is your 200?  I would go with the 200, you pull the throttles back for cruise, and you will get excellent mileage, plus you'll have the power and speed if yoiu ever need it, with the 150, you will always be in the upper RPM range.

im with FP, go with a 200... when i ran a 112 jonny on my boat, WOT 38 mph with 1 soul onboard and less than 1/4 tank of fuel... with my 200 erude, 37mph at 3700 rpm with 3 souls onboard and over 3/4 tank of fuel. at 37 mph my fuel burn is about the same, but i still have a ton of power on tap if i have to run from any storms

[TheKid]

TheKid-  What are your miles per hour at cruise and WOT with that 140?

I was trying to figure out if a 150 would be enough horsepower for a 222FF.  I'm sure most on this site would say it would be a little underpowered, but I just need to cruise at 24-26 MPH.  My question is, would it be more fuel efficient to run a 150 at slightly higher RPM's or a 200 with the throttle pulled back a little.  My initial guess would be the 150 would be more efficient.  I currently have a Yamaha 200 Salt Water Series carbed motor that I plan to mount but I'm scared of the fuel consumption.  When I got the boat it had an old Evinrude 150 on it and I heard it ran pretty good with that motor before it seized up.  Its a 75 22-2 FF.

Cruise at 20 WOT 33. The 140 is not bad. I get up on plane in a few seconds and it does the job. However, if I had the cash and thought the hull worth it I would love to have a 200 or 225hp motor. This motor came with the boat and has been a solid performer for sure.

[TheKid]

Unless something is wrong, a carburated two stroke outboard wont burn more than 10% of its rated horsepower in gallons per hour at full throttle. 140 hp= 14 gallons per hour. This formula holds very true and has stood the test of time. You are a little light on horsepower for a 22-2FF so I'm going to say you need a good 4400 rpm to get to about 26- 27 mph. If your motor is propped right, you should be turning around 5500 WOT. So if the math holds you should be burning around 11.2 gph at cruise. 7.5 hours of burn @85 gallons or about 197 mile range. So you want to have 30% reserve for your average trip or 28 gallons when you pull her into the ramp. So 56 gallons for your trip will give you a safe, usable range of 130 miles with a safe reserve. Sounds like no problem for your Tuna run. Once you get a flow scan and a GPS you can have very predictable trips for your fuel burn. Of course running offshore is not like flat water running, hence the 30% reserve factor.

Thanks Fitz. This is the exact kind of reasoning I was looking for, well, other then another FF with a 140 and floscan.

I came up with close the same range at 170 miles for a full tank assuming 2 miles/gallon.

I 'm pretty darn sure I have the range too. Just in case, I'll add four jerry cans to the load.

Thanks to all!

Cross your fingers, Albacore Tuna here I come!!!

[gran398]

Good luck Kid!

This may sound simplistic, but want to mention it...

Dump the jerry cans every 15 miles on the ride out, tie them to the bow.

When you start fishing, the cockpit is clear.

You'd be surprised at the folks you see that do the opposite, dump them on the ride home.

[TheKid]

Good luck Kid!

This may sound simplistic, but want to mention it...

Dump the jerry cans every 15 miles on the ride out, tie them to the bow.

When you start fishing, the cockpit is clear.

You'd be surprised at the folks you see that do the opposite, dump them on the ride home.

That is the plan.

thx

[saltfly]

You may still be able to get what is called a fuel bladder. They where flexible fuel tanks. Just for that purpose. I don’t know if their still available. But it would be worth looking into. You fold it up and put it away when it is empty. We use to use them years ago. The Military started their use. Not something you would use every day, but once in a while.

[c master]

I would guess the bladders are still available and they are nice.  We use a huge one for diesel on a 48' Cavileer to run from Port Fourchon, La. to Isla Mujeres.  Running pretty low coming in to Mexico but the FloScan's are accurate and we only go when the sea is flat and the weather's very stable.

It's pretty amazing how throttling back just a little will save a ton of fuel even on my 170.  No question I'm going slower but over a long run across the bay it really only adds a few minutes (3 or 4?) to the travel time.