I am preparing for a 75-80 mile trip home down the intercoastal and was curious as to what the fuel burn on my 2000 Honda 9.9 4-stroke may be in GPH. Its pushing a 99 H270/260 wing keel. When I had a sea trial on Saturday I was a little disappointed in the speed of the boat under power as it was only getting 5mph at full throttle. Then again we had the current coming at us along with the wind so that may have been a contributing factor for us not reaching hull speed. I am hoping to be able to run at 80% power on the way home but to tell you the truth the motor didn’t sound like it was reaching full RPM at 100% throttle but theres nothing wrong with the motor, it may just be a power prop instead of cruise prop. Anyway, it’s a long post just to try to figure out the fuel burn of the engine isn’t it. J
Preparing for 75 mile trip home.
- Thread starter av8erdunn
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Does it have an alternator hooked up to the battery? If so, have you checked its output?
My Honda 8HP does have an alternator and has a plug/cable to charge the battery - I think it maxes out at about 5 amps, so it doesn't charge it fast. I don't know if this was an option, or is on all Hondas > 8 HP. If you have a cable to the battery, and don't have electric start, seems likely it is to charge it.
Were you doing 5 MPH SOG or over the water? I'd think the hull speed is maybe 6 MPH or so, so if that is SOG and you had a current, that is probably about right. I suspect my 8HP on the 23 wing keel gets to hull speed at maybe 50 to 60% throttle - though I have no way of really measuring, lacking a tach.
Were you doing 5 MPH SOG or over the water? I'd think the hull speed is maybe 6 MPH or so, so if that is SOG and you had a current, that is probably about right. I suspect my 8HP on the 23 wing keel gets to hull speed at maybe 50 to 60% throttle - though I have no way of really measuring, lacking a tach.
That's what I was thinking. I am hoping once I get into the intercostal I will be able to back off the throttle a bit to get a bit better fuel economy.
I have that same motor on the H240. It will do hull speed at about 50-70% throttle (5.5mph) I have not check the fuel burn lately but .5 to max .75 gph is what I remember. It's a Honda, so by definition it is good on fuel burn.
If you can trace the wires to anything other than the starter motor and ground, then you just might have an alternator, rectifier, etc..
The 9.9hp honda does have an alternator. I was out on Lake Erie today and the voltage while running the Honda was 15.7V ...just FYI. Mine is around model year 2000.
spoke with Av8erdunn this morning. Advised that he finally located the cable kit for his Honda 9.9 which he purchased for his older motor. I advised him to call if he needs any help when putting on. As for the top of the pedestal, I advised against any set up for controls on top of the cover plate with the four drink holders telling him to purchase the Edson controls and remove that part of the cover plate with the drink holders facing the rear to allow the Edson Control handles to operate freely.
We'll we made the trip home and for the most part it was uneventful. The engine ran wonderful and I was able to squeeze about 5 hours out of a three gallon tank and still had about a quart left. The only issue I had was my ignorance and I am kinda embarrassed but I will tell y'all anyway. When we departed it was daylight and motor was running great. As the sun went down a light caught my eye. It was the green check oil light on the motor. Here I am in a windy ship channel with an engine with low oil and strong winds that's going to blow me aground if I don't anchor but I wasn't in a good place to try that. Then I had a bright idea. Kill the engine and quickly add oil to make the light go off and then get to a safe place to anchor and look into it more. So I had the wife drive while I did exactly that. Added a little and got back underway; light didn't go off. I'm thinking man this thing must have been really low so I added a little more for a total of half a quart. Started her back up and she started puking oil out of the intake and runnin like crap. At this time a barge is about a mile away which is great timing for this to be happening. It smoked and bucked for about two minutes and cleared up so we continued on. Finally anchored off and told the wife I need to get some oil out so I got the manual out and realized the oil drain is on the side of the motor. Great!!!! I know how this is going to end. One of three things is gonna happen.
1- I'm gonna spill oil in the water.
2- gonna drain more than I should and won't be able to get it back in.
3. I will have oily hands and drop the plug in the water.
None of these was going to be good for us so we elected to leave it alone and go to sleep after having a few adult beverages. Slept lake a baby all night and awoke the next morning feeling refreshed.
Started the motor and she missed a little but not bad clearing up once I got the rpm's up. She run fine for the next 10 hours of the trip and got us home just as she was supposed too. We docked her tilted the motor and started the 5 hour trip home.
Half way home I started thinking to my self, maybe I shouldn't have tilted it. I know it's still overfill and I am hoping by titling it up oils isn't going to go places it shouldn't while tilted. I guess I will find out next weekend when I go back to install my remote engine controls.
It was a lesson learned but I guarantee it will not happen again. Oh and the green light means its fine. It turns red when it's low on oil. I couldnt even see the green light until the sun started going down so that's what alarmed me. Considering I was nervous anyway a new light was bad to me. Oh well it was a wonderful trip anyway.
1- I'm gonna spill oil in the water.
2- gonna drain more than I should and won't be able to get it back in.
3. I will have oily hands and drop the plug in the water.
None of these was going to be good for us so we elected to leave it alone and go to sleep after having a few adult beverages. Slept lake a baby all night and awoke the next morning feeling refreshed.
Started the motor and she missed a little but not bad clearing up once I got the rpm's up. She run fine for the next 10 hours of the trip and got us home just as she was supposed too. We docked her tilted the motor and started the 5 hour trip home.
Half way home I started thinking to my self, maybe I shouldn't have tilted it. I know it's still overfill and I am hoping by titling it up oils isn't going to go places it shouldn't while tilted. I guess I will find out next weekend when I go back to install my remote engine controls.
It was a lesson learned but I guarantee it will not happen again. Oh and the green light means its fine. It turns red when it's low on oil. I couldnt even see the green light until the sun started going down so that's what alarmed me. Considering I was nervous anyway a new light was bad to me. Oh well it was a wonderful trip anyway.