Author Topic: Outboard engines  (Read 2768 times)

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Offline gonfishen

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Outboard engines
« on: December 28, 2011, 10:14:45 PM »
Ok this is for all you marine engineers out there. i have been around boat engines most of my life and i have always been told that if you are not using the boat for a few days, run the engine dry (2 stroke only) but the other day an outboard mechanic advised me not to bother and that it was ok to leave fuel in the motor he also said it was better to leave fuel in as it aided starting the next time and that it was also better to leave fuel in the engine when towing the boat long distance. This advise was given about my outboard which is about 20years old. What are your views  ??? ??? ??? ???
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Offline RebsWA

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Re: Outboard engines
« Reply #1 on: December 28, 2011, 10:49:11 PM »
First, I am not a marine engineer but have been around, owned and worked on 2 stroke outboards (mainly Johnson/Evinrude) for some 40 odd years.
As your motor is 20 years old I expect it will be a carburettor model and you premix the fuel in the tank.
If that is correct I would ignore the recent advise and run it dry if you do not plan to use it for a while as that is best practice IMO.
If your motor is not a carburettor with premixed fuel then you need to post up details of your engine for further assessment.
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Offline gonfishen

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Re: Outboard engines
« Reply #2 on: December 28, 2011, 11:04:18 PM »
Thanks for the reply my motor is a Johnson, carby, 70hp, pre mix in the fuel tank at 50 to 1, my thoughts are still to run it dry if it is not used for a week or more, i did not belive the mechanic but i thought i would ask the question anyway in case i was wrong.
« Last Edit: December 29, 2011, 07:42:01 AM by gonfishen »
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Offline RebsWA

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Re: Outboard engines
« Reply #3 on: December 28, 2011, 11:13:18 PM »
Thanks for the reply my motor is a Johnston, carby, 70hp, pre mix in the fuel tank at 50 to 1, my thoughts are still to run it dry if it is not used for a week or more, i did not belive the mechanic but i thought i would ask the question anyway in case i was wrong.
Run it dry mate!
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Offline bobnrob

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Re: Outboard engines
« Reply #4 on: December 29, 2011, 08:29:54 AM »
Run it dry mate!

Wasn't it something about the oil in the fuel would harden if left too long, or something along those lines.
Was a while ago now & just did it because I was taught it was the right thing to do, & was the practise with everyone else as well.

Also did it with any other 2 stroke engine I'd had/used - mower, gennie etc
Bob and Robyn


Offline RebsWA

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Re: Outboard engines
« Reply #5 on: December 29, 2011, 11:55:57 AM »
Wasn't it something about the oil in the fuel would harden if left too long, or something along those lines.
Was a while ago now & just did it because I was taught it was the right thing to do, & was the practise with everyone else as well.

Also did it with any other 2 stroke engine I'd had/used - mower, gennie etc
If you leave premix in your carby/ies the petrol evaporates off and leaves the oil behind so when you prime up to start next time you get a double dose of oil which can foul the spark plug and make starting difficult if not just a smokey start.
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Offline krisandkev

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Re: Outboard engines
« Reply #6 on: December 29, 2011, 12:16:48 PM »
Always been the way, 2 stroke you unplug the hose and run it dry, 4 stroke you do not. Naturally if you are lucky enough to use your boat regularly I do not think it is as important to run it dry. With me, unfortunately I do not get to take the boat out very often!  In fact, it has been months.  :(
I also do not leave mixed fuel in the tanks too long as the oil brakes down.
Kris and Kev
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