Gas Mileage got worse

[pennparkerh2o]

I bought a 07 2520 xl with a f250 in April. When I ran the boat back from the dealer (50 mile run), the gas mileage was from 2 to 2.3 miles a gallon. The seas were a 2, maybe 3 foot medium chop.

Ever since that day, I have been getting 1.5 to 1.7 miles a gallon in all conditons.

What do you think guys?

 

[MaxOut]

Was this boat new o hours? If so this would explain the poor fuel consumption. During the first 20 Hours of operation the dealer will de-tune the motor and will re-tune it when the 20 hour service is performed. This is done to protect the engine during break in. Your milage will also vary depending on the octane of the fuel. I use premium grade not only for performance benifits but higher octane fuel will remain stable longer. Just my opinion. I have a 07 2520SL with rear station and 4-stroke Yamaha 250 and I burn 10-11GPH @ 4200 RPMS Moving @ 25 MPH with a full tank of fuel and gear. Hope this helps..

 

[Megabyte]

I would call your dealer and pose that question to the service manager, but I believe that maxout is correct.
How many hours on the motor?

BTW - Welcome aboard maxout!

 

[DaleH]

You can also lose RPMs, speed, and MPG once bottom growth starts to form on the hull. And in hotter weather, all normally aspirated combustion engines lose punch ...

My boat ALWAYS run the best in the cool SPring weather with a freshly painted bottom.

Oh yeah ... boats also tend to accumulate gear, hence WEIGHT, as the season progress too !

 

[pennparkerh2o]

When I ran the boat back from the dealer, the boat had about 7-8 hours on it. It currently has about 65 hours.

As for fuel, I fill up with 89 octane which yamaha recommends for the f250.

I had my 20 hour service done but there was no tuning done on the engine.

 

[pennparkerh2o]

So you guys are saying 1.5 to 1.7 miles a gallon is normal? Keep in mind I usually fish with one other guy. As for gear, I have a 24 gallon portable livewell that weighs about 220 pounds when filled to the top.

 

[hakr]

Was this boat new o hours? If so this would explain the poor fuel consumption. During the first 20 Hours of operation the dealer will de-tune the motor and will re-tune it when the 20 hour service is performed. This is done to protect the engine during break in.

This is the first I have heard that dealers detune outboards during break-in. Is this true of all the Yamahas on Parkers? What's the source of this info?

 

[Outta Here]

Was this boat new o hours? If so this would explain the poor fuel consumption. During the first 20 Hours of operation the dealer will de-tune the motor and will re-tune it when the 20 hour service is performed. This is done to protect the engine during break in.

This is the first I have heard that dealers detune outboards during break-in. Is this true of all the Yamahas on Parkers? What's the source of this info?

Not too sure about that. I've had 3 Yamahas. Never took one back for the 20 hour "de-tuning session". I can think of nothing harder on a brand new motor than to purposely "de-tune" and cause motor to work extra hard. Yamaha's own instructions are to (basicly) "bring motor up to clean plane smoothly avoid wide open take-offs or max RPM."

As far as your gas milege goes, look at Yamaha Performance Bulletins. FWIW, the 28' Parker cabin boat with 2-225-4 Yamahas gets 2 plus MPG at 32 MPH. :wink:

 

[PaulH / Emily S]

Did you lose any speed ? Have you verified this with a GPS ? What is the source for speed on your fuel management gauge (GPS, speedo, etc) ?

The source of your problem could simply be that your speedometer isn't working properly.

I just bought a new F250 and ran it plenty in it's early hours, it wasn't detuned or whatever, that's a lot of bunk.

On an XL hull, I would think you'll easily approach 2.5 MPG.

 

[Claymar]

When I was in high school, back when dinasaurs roamed the earth, was the first and last time I heard the detuning myth. Back then the hot rod of the day was the 66 Mustang. The word then was that the cars were "detuned" to keep people from killing themselves with all the raw power.

Detuning the Yamaha's is the first variation I've ever heard on this myth.

My 150 has averaged 2.5 to 3 (load dependant) from day one. Its now approaching 200 hours.

 

[MaxOut]

Was this boat new o hours? If so this would explain the poor fuel consumption. During the first 20 Hours of operation the dealer will de-tune the motor and will re-tune it when the 20 hour service is performed. This is done to protect the engine during break in.

This is the first I have heard that dealers detune outboards during break-in. Is this true of all the Yamahas on Parkers? What's the source of this info?

The dealer I purchased my Parker from said they de-tune the engine to protect it during break in and had detailed instructions on how to break the motor in. They paid for the 20 hour service to ensure you bring it back to have it re-tuned and checked. Most factory issues will show up in the first 20 hours so it is in there best interests to offer this. They include it in the price of a new boat. I ran the boat according to the break in procedure and did not notice a difference in performance after the 20 hour service. The technician can also see the RPM spikes recorded in the computer to see if you actually followed the break in process properly. According to Yamaha you can void your warranty if the break in procedure is not followed. I too noticed a difference in fuel consumption after break in but not a noticable difference in performance. I do not go by the Yamaha flow meter, I top the boat off after each trip and record GPS figures to determine fuel consumption. 8)