User Tag List

Page 1 of 2 1 2 LastLast
Results 1 to 15 of 23
  1. #1
    Join Date
    Jan 2003
    Location
    beaumont, TX
    Posts
    175
    Thanks (Given)
    5
    Thanks (Received)
    0
    Likes (Given)
    19
    Likes (Received)
    3
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Merc 300R Fuel Consumption

    Guys,

    I did a little searching but couldnt find anything.

    What does a 300R burn on average per hour at wide open 6400 rpms ?

  2. #2
    Join Date
    Jul 2021
    Location
    Pompano Beach
    Posts
    144
    Thanks (Given)
    0
    Thanks (Received)
    16
    Likes (Given)
    0
    Likes (Received)
    38
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    LOLOLOL......when I'm running mine at WOT I'm too busy to look. At 4000 I burn 11 gph at 4500 16 gph. The 30 gph figure sounds about right, but I want to say that I've seen 38 gph but not sure, at WOT.
    Last edited by Capt j; 08-04-2022 at 10:22 AM.

  3. #3
    Join Date
    Sep 2019
    Location
    Lake Keowee, SC
    Posts
    243
    Thanks (Given)
    8
    Thanks (Received)
    25
    Likes (Given)
    0
    Likes (Received)
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Hebert519 View Post
    Guys,

    I did a little searching but couldnt find anything.

    What does a 300R burn on average per hour at wide open 6400 rpms ?
    my best guess is about 30 gph based on other mercury engines.

  4. #4
    Join Date
    Aug 2007
    Location
    DE WITT AR
    Posts
    276
    Thanks (Given)
    3
    Thanks (Received)
    6
    Likes (Given)
    1
    Likes (Received)
    6
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My 300xs burns about 26-27 GPH at 5950 RPM. I would expect that a 300r would burn slightly more.

  5. Likes Hebert519 liked this post
  6. #5
    Join Date
    Jul 2021
    Location
    Pompano Beach
    Posts
    144
    Thanks (Given)
    0
    Thanks (Received)
    16
    Likes (Given)
    0
    Likes (Received)
    38
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    My 300R yesterday at WOT was burning 26.8 gph at 6260 with a fishing load. I've seen as high as 30 GPH at 6400 rpms with a bigger prop and light load.

  7. #6
    Join Date
    Apr 2003
    Location
    New Smyrna Beach, FL./LOTO
    Posts
    6,606
    Thanks (Given)
    600
    Thanks (Received)
    900
    Likes (Given)
    1679
    Likes (Received)
    7085
    Mentioned
    3 Post(s)
    Tagged
    1 Thread(s)
    I don't know what the burn rate per hour is but I looked at my smartcraft screen tonight in 36 Doug Wright and at 83 mph it gets 2.65 mpg. This is at 4,000 rpm and the engines are not making any boost yet-pretty good all things considered.

    Joe

  8. Likes Beak Boater, lance liked this post
  9. #7
    Join Date
    Apr 2001
    Location
    Illinois
    Posts
    1,560
    Thanks (Given)
    10
    Thanks (Received)
    77
    Likes (Given)
    141
    Likes (Received)
    588
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    The 4 strokes really shine at cruising speeds for mpg. My friends with 300R's get double the gas mileage I get with my 300X. Added benefit is the 300R burns 87 octane not the premium I need to run. I have 300R's on order and should be here real soon.

  10. #8
    Join Date
    Sep 2019
    Location
    Lake Keowee, SC
    Posts
    243
    Thanks (Given)
    8
    Thanks (Received)
    25
    Likes (Given)
    0
    Likes (Received)
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by JPEROG View Post
    I don't know what the burn rate per hour is but I looked at my smartcraft screen tonight in 36 Doug Wright and at 83 mph it gets 2.65 mpg. This is at 4,000 rpm and the engines are not making any boost yet-pretty good all things considered.

    Joe
    If the speed and mpg are correct, the engines are pulling 31.3 gph at 4000 rpm. I assume those are twin engines so 15.7 gph per engine at 4000 rpm. I find that very reasonable. I have a 24 ft Checkmate with a single 300R, and at 3000 rpm I am running about 29 mph and pulling 6.1 gph which equals 4.75 mpg. I think at 4000 rpm mine would pull about 8 gph but it would only be doing around 42 mph. Considering the weight your pushing and speed your running, that's impressive.

  11. #9
    Join Date
    Jul 2021
    Location
    Pompano Beach
    Posts
    144
    Thanks (Given)
    0
    Thanks (Received)
    16
    Likes (Given)
    0
    Likes (Received)
    38
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pulsare2400 View Post
    If the speed and mpg are correct, the engines are pulling 31.3 gph at 4000 rpm. I assume those are twin engines so 15.7 gph per engine at 4000 rpm. I find that very reasonable. I have a 24 ft Checkmate with a single 300R, and at 3000 rpm I am running about 29 mph and pulling 6.1 gph which equals 4.75 mpg. I think at 4000 rpm mine would pull about 8 gph but it would only be doing around 42 mph. Considering the weight your pushing and speed your running, that's impressive.
    Mine only uses 11.6 at 4,000 and 15.6 at 4500 rpms.

  12. #10
    Join Date
    Jan 2004
    Location
    FLA
    Posts
    739
    Thanks (Given)
    7
    Thanks (Received)
    74
    Likes (Given)
    119
    Likes (Received)
    497
    Mentioned
    0 Post(s)
    Tagged
    1 Thread(s)
    Joes numbers are a 36 DW with 450s
    24 Twister

  13. #11
    Join Date
    Apr 2001
    Location
    Norway
    Posts
    935
    Thanks (Given)
    61
    Thanks (Received)
    13
    Likes (Given)
    353
    Likes (Received)
    182
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hi!

    This is a Phantom 25 with a 450R:

    2000 rpm @ 29 mph @ 20 liter / 5,26 gal per hour
    2500 rpm @ 36 mph @ 27 liter / 7,1 gal per hour
    3000 rpm @ 42 mph @ 40 liter / 10,5 gal per hour
    3500 rpm @ 52 mph @ 48 liter / 12,6 per hour
    4000 rpm @ 59 mph @ 59 liter / 15,5 gal per hour
    4500 rpm @ 67 mph @ 72 liter / 18,9 gal per hour
    5000 rpm @ 75 mph @ 85 liter / 22,3 gal per hour
    5500 rpm @ 83 mph @ 126 liter / 33,15 gal per hour
    6,000 rpm @ 89 mph
    6300 rpm @ 94 mph

    I do not have figures for wot, but I estimate 170 liter per hour.

    Cheeers, Toffen
    Last edited by Toffen; 10-25-2022 at 01:37 PM.

  14. #12
    Join Date
    Sep 2019
    Location
    Lake Keowee, SC
    Posts
    243
    Thanks (Given)
    8
    Thanks (Received)
    25
    Likes (Given)
    0
    Likes (Received)
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Toffen View Post
    Hi!

    This is a Phantom 25 with a 450R:

    2000 rpm @ 29 mph @ 20 liter / 5,26 gal per hour
    2500 rpm @ 36 mph @ 27 liter / 7,1 gal per hour
    3000 rpm @ 42 mph @ 40 liter / 10,5 gal per hour
    3500 rpm @ 52 mph @ 48 liter / 12,6 per hour
    4000 rpm @ 59 mph @ 59 liter / 15,5 gal per hour
    4500 rpm @ 67 mph @ 72 liter / 18,9 gal per hour
    5000 rpm @ 75 mph @ 85 liter / 22,3 gal per hour
    5500 rpm @ 83 mph @ 126 liter / 33,15 gal per hour
    6,000 rpm @ 89 mph
    6300 rpm @ 94 mph



    I do not have figures for wot, but I estimate 170 liter per hour.

    Cheeers, Toffen
    That is really impressive Toffen. My 300R pulls about 6 gph @ 3000 rpm in my 24 Checkmate, but it is only doing 29 - 30 mph. So you should really compare the fuel consumption at similar speeds not similar rpm. Your 450R pulls 5.26 gph at 29 mph!! That is actually slightly less than the 6.1 gph mine pulls at that same speed!! Will it stay on the plane at 2000 rpm?? How heavy is your Phantom with the engine, fuel, you in it and ready to run? I would guess mine is around 3100 - 3200 lbs (about 1430 kg) with my wife and me in it.

    Best Regards,
    Glenn

  15. #13
    Join Date
    Jan 2003
    Location
    beaumont, TX
    Posts
    175
    Thanks (Given)
    5
    Thanks (Received)
    0
    Likes (Given)
    19
    Likes (Received)
    3
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pulsare2400 View Post
    That is really impressive Toffen. My 300R pulls about 6 gph @ 3000 rpm in my 24 Checkmate, but it is only doing 29 - 30 mph. So you should really compare the fuel consumption at similar speeds not similar rpm. Your 450R pulls 5.26 gph at 29 mph!! That is actually slightly less than the 6.1 gph mine pulls at that same speed!! Will it stay on the plane at 2000 rpm?? How heavy is your Phantom with the engine, fuel, you in it and ready to run? I would guess mine is around 3100 - 3200 lbs (about 1430 kg) with my wife and me in it.

    Best Regards,
    Glenn
    For me, i would rather know how much fuel is burned per hour at a certain RPM. There are so many variables with speed vs. rpm for each boat.

    The one thing that may change is how much load is being applied at an RPM affecting fuel burn.

    My cruising speeds/rpms change drastically with props but i think looking at a fuel burn per hour at an RPM is more reliable than speed. I could be wrong though, so im here to learn.


    Im running a 300r on a 23' V bottom, and need to know my range - reason for the post.

    Two of my setups are

    26 pitch pro max - 5000 RPMS @ 60/62 mph

    26 pitch Bravo FS - 5000 RPMS @ 56 mph


    Pretty big difference in range at an hour run time, but how much does load affect the fuel burn on that.

  16. #14
    Join Date
    Sep 2019
    Location
    Lake Keowee, SC
    Posts
    243
    Thanks (Given)
    8
    Thanks (Received)
    25
    Likes (Given)
    0
    Likes (Received)
    62
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Hebert519 View Post
    For me, i would rather know how much fuel is burned per hour at a certain RPM. There are so many variables with speed vs. rpm for each boat.

    The one thing that may change is how much load is being applied at an RPM affecting fuel burn.

    My cruising speeds/rpms change drastically with props but i think looking at a fuel burn per hour at an RPM is more reliable than speed. I could be wrong though, so im here to learn.


    Im running a 300r on a 23' V bottom, and need to know my range - reason for the post.

    Two of my setups are

    26 pitch pro max - 5000 RPMS @ 60/62 mph

    26 pitch Bravo FS - 5000 RPMS @ 56 mph


    Pretty big difference in range at an hour run time, but how much does load affect the fuel burn on that.
    I agree, we are saying the same thing. I also have a 300R with a 24 Bravo FS and a 24 ProMax. If you divide your speed in mph by your fuel flow in gph you you get mpg. Your best range will be at your highest mpg. In the case of Toffen's Phantom 450R based on his numbers 2000 rpm = 5.5 mpg, 2500 rpm = 5.07 mpg, and 3000 rpm =3.80 mpg. So his range is best at 2000 rpm if he really wanted to run the engine as such low rpm. His engine uses more fuel flow at 3000 rpm than mine and his mpg is a bit less, however at 2000 rpm his mpg is better than mine. At least that is how I would view it. In my case their is less difference between the FS and the ProMax but the ProMax will run 76 mph loaded light but the FS more like 73 mph. However, if I load the boat with more fuel and weight the slip increases on the ProMax more than the FS. I have ordered a labbed 26P ProMax to try, and I would guess that should improve the mpg at 3000 rpm in my case.

  17. Likes Hebert519 liked this post
  18. #15
    Join Date
    Jul 2021
    Location
    Pompano Beach
    Posts
    144
    Thanks (Given)
    0
    Thanks (Received)
    16
    Likes (Given)
    0
    Likes (Received)
    38
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Hebert519 View Post
    For me, i would rather know how much fuel is burned per hour at a certain RPM. There are so many variables with speed vs. rpm for each boat.

    The one thing that may change is how much load is being applied at an RPM affecting fuel burn.

    My cruising speeds/rpms change drastically with props but i think looking at a fuel burn per hour at an RPM is more reliable than speed. I could be wrong though, so im here to learn.


    Im running a 300r on a 23' V bottom, and need to know my range - reason for the post.

    Two of my setups are

    26 pitch pro max - 5000 RPMS @ 60/62 mph

    26 pitch Bravo FS - 5000 RPMS @ 56 mph


    Pretty big difference in range at an hour run time, but how much does load affect the fuel burn on that.
    Get a vessel view or smart craft gauge, either will show you real time GPH. Load changes it a lot. I have a 20' Lake and Bay backwater flats boat 300R. 10" bob's jack plate. I get on plane with the motor down, at 4000 rpms trimmed down I burn 13.8 gph and only like 42 mph, once I start trimming up speed will increase to 46-48 mph, BUT GPH will also go down to 11.8 when trimmed properly. So load has a lot to do with GPH even at the same rpm. 4500 rpms, I'm around 52 mph usually and 15.8, but again if I trim down and run with the bow buried (maybe cause it's rough), GPH will go up to as much as 17.2 GPH. If you're spending this kind of money on the motor, why not spring for a vessel view, or at least a smartcraft gauge that will show fuel burn, as well as other functions like water pressure.

Page 1 of 2 1 2 LastLast

Similar Threads

  1. Mercury Tech: XR4 - Fuel Consumption
    By James Bozeman in forum Technical Discussion
    Replies: 6
    Last Post: 10-20-2010, 10:24 PM
  2. can anyone tell me fuel consumption on a 260 GPH?
    By hst714 in forum Technical Discussion
    Replies: 4
    Last Post: 08-31-2010, 10:15 PM
  3. 95 XRI 150 fuel consumption
    By THEFERMANATOR in forum Technical Discussion
    Replies: 4
    Last Post: 12-10-2007, 10:54 PM
  4. Fuel consumption
    By Gerben in forum Technical Discussion
    Replies: 2
    Last Post: 01-28-2003, 10:25 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •