Welcome Guest - Sign Up today
Welcome Guest - Sign Up today
Store Links Mobile - Shop Now



Help Tip: If you have a question that has not been answered to your satisfaction in the archives, it is always best to start a new thread of your own. By starting your own thread, you will receive the maximum number of views by forum members.

Below are some additional forum policies in hopes of all iboats members will follow, Thank you.

1. Please do not reply to old topics or hijack existing topics. Old topics of a technical nature are like a library book, Please do not write in them.

2. Old topics should be considered archives and used for reference only. Please do not reply to them.

3. Do not take over someone elseís topic (aka hijack) with your own question, even if it is similar. If you have a question that has not been covered to your satisfaction in the archives, it is always best to start a new topic of your own.

4. If you have a question for the original poster (OP) and the topic is over 30 days old, send the OP a PM, he may not even visit the forums any longer, or may not notice your question in the old topic.

5. By starting your own topic, you will receive the maximum number of views by forum helpers that may not even notice your question when itís posted at the end of someone elseís topic. And those answers will be specific to your particular issue.

6. Please do not post to topics that have been inactive for more than 3 months unless you are the original poster. We have very active forums and any topic that remains inactive for that long should be considered "dead". It is especially confusing when there is an entirely new question posted to an old topic.

7. Posting at the end of any topic is considered to be hijacking the original posters topic which in turn subjects the topic to be closed if it continues to happen thus not making it fair to the original poster in the future had for some reason he/she needed to return for additional information or provide an update of the problem solved which is always welcomed within a reasonable amount of time frame.

8. Please note that you should see a red banner pop up near the bottom of each inactive topic asking you not to reply to old topics. The Red banner will read: Please note this topic has been inactive for 90 days. For the best results, please start a new topic.

Thank you all in advance for doing your part in helping iboats run a smooth ship.

Additional forum rules linked below.
See more
See less

1976 6hp Johnson fuel consumption.

  • Filter
  • Time
  • Show
Clear All
new posts

  • 1976 6hp Johnson fuel consumption.

    I have a 1976 6hp Johnson Seahorse (6R76) and was wondering if anyone knew what sort of fuel consumption it was supposed to have at wide open throttle. I have it on a 14' aluminum boat with a max capacity of 600 lbs. The boat itself weighs about 150 lbs or so. With the boat fully loaded I can get about 7.5 mph out of it.

    It's not like I plan to run it at WOT for hours on end, I'd just like to know so I can be sure not to accidentally run it out while out on the lake.

  • #2
    The old rule of thumb for 2 stroke outboards is 10% of hp in gallons per hour at WOT. .6 gallons per hour sounds about right for that motor. I don't know how many hours I put on our old 6 Johnson as a kid, but I ran it a lot, and it seems like I could run pretty much all weekend on a 6 gal tank.


    • #3
      If you're planning a longer cruise, bring an extra fuel tank, or at the very least a small gallon sized Jerry can with some extra mixed fuel as a get me home backup plan.
      Share A Project Page for 1971 GW Invader Banchie 13
      Share A Project Page for 1976 American 18
      Share A Project Page for 1974 American 15


      • #4
        It's around 10 to 12 % depending on OB fabricator provided that OB runs at max wot rpm range factory stated. You could be lugging the OB and not knowing anything about it, a induction tach will tell, revving at full wot towards the min or lugging side is bad, a less pitch prop will cure it..

        Happy Boating
        Sea Rider 320, 380 Sibs, 450 Rib, 2 Strokes Tohatsu 5,18 & 30 HP Proud Smokers


        • #5
          Thanks for the input, guys.
          The motor is completely stock, so I have no plans on changing the prop. I also run the boat on smaller lakes and it would never take more than 30 minutes or so to go from end to end at WOT.

          With the info you guys provided even if I was getting lousy economy and burning almost double the gas I should be, I could run a 3 gallon tank for about 3 hours. That means I should almost never have to worry about it as long as I start the day with the tank full.


          • #6
            Factory delivered props are medium pitched, probably not the best one OB needs to run inside safe wot rpm range specially if powering a large combo at wot. Can't possibly know without installing an induction tach...

            Happy Boating
            Sea Rider 320, 380 Sibs, 450 Rib, 2 Strokes Tohatsu 5,18 & 30 HP Proud Smokers


            • #7
              Sign up today
              From the mid 70s to mid 80s we had a 5 1/2 which was a lower revving(500 rpm) version of that engine. It ran a very long time(7hr+) on the 5 gal tank.

              As for propping it, the factory prop was a 8 X 7 1/4

              iboats has a selectionand two more pitches, but they are both higher