fuel mixture in new 15 hp yamaha

wadwizzle

Recruit
Joined
Dec 15, 2007
Messages
1
hello, just bought a 2 stroke 15 hp here in mexico. It is model E15D and the manual says to use 50:1 ratio but all Yamaha sites show to use a 100:1 ratio. I can't find an email address for Yamaha and it is impossible to just call them from Mexico. Does anyone know if a brand new E15D has different carbureation from the F15 series? Is the manual wrong or is the company just not advertising its products honestly? I don't want to ruin the engine by using the wrong mixture.
Thanks for any help.
 

BruceAML

Petty Officer 1st Class
Joined
Feb 26, 2007
Messages
371
Re: fuel mixture in new 15 hp yamaha

Yamaha motors sold in Mexico are different than those sold in the US and Canada. You can contact Yamaha in Mexico at this web site:

imemsa.com.mx/

In the meantime use 50:1 mix of a high quality TCW-III oil such a Yamalube 2-m.
 
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rorypff

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Oct 18, 2007
Messages
16
Re: fuel mixture in new 15 hp yamaha

You are only ment to use a 1:50 ratio for the first 10 hours whilst running the engine in. There after the ratio is 1:100 using any good outboard 2 stroke oil. Using a 1:50 continuosly will carbon the engine up and give you endless problems with oiled up spark plugs.
 

deejaycee_2000

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Mar 28, 2006
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3,447
Re: fuel mixture in new 15 hp yamaha

50:1 always ........ never ever run the fuel mixed 1:100 .....
 

rorypff

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Oct 18, 2007
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Re: fuel mixture in new 15 hp yamaha

Then why does the owner's manual specify a 1:100 ratio for all motors up to 30 HP?
 

JB

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Mar 25, 2001
Messages
45,907
Re: fuel mixture in new 15 hp yamaha

Historically, engines that ran 100:1 ratios (at makers recommendation) ran fine but developed internal corrosion in storage.

That is why OMC revised recommendations to 50:1 for all the engines that they had set at 100:1. Other makers followed suit. I think that was about 20 years ago.

Using 50:1 will not hurt your engine, cause excessive carbon buildup or foul the plugs.

Using 100:1 will make less smoke and pollution, but don't store the engine for long periods without running 50:1 in it for a few minutes to coat internal parts with a better film of oil.
 

rorypff

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Oct 18, 2007
Messages
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Re: fuel mixture in new 15 hp yamaha

Just looking at the Owners Manual for the 2005 15D still recomends 1:100 after running in. I would have thought that fogging before storage gave adequate lunbrication.
 

JB

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Mar 25, 2001
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Re: fuel mixture in new 15 hp yamaha

I would think that fogging would solve the potential corrosion threat.

If the Yammy book says 100:1 I would run 100:1, though I really think the objective is to reduce pollution rather than to improve performance.
 

rodbolt

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Joined
Sep 1, 2003
Messages
20,066
Re: fuel mixture in new 15 hp yamaha

the E15d is an 05 or newer Enduro15. its not avalible in the US and hasnt been for maybe 20 years.
its built with slightly different specifications than the US 2 stroke 15. the F15 is a four stroke,totally different animal.
oils outside the US are very different, here in Venezuela,hence the rodbolt1.0, the TCW3 oil here is very very thin and has almost no amonia smell. even the yamalube is thinner here than the US.
JB is quite right about OMC and the fact that 50to1 wont create a carbon issue. if the cooling and fuel is kept in new condition and the engine wont sit idle for more than 2 weeks 100 to 1 may work ok. however fuels and lubricants are vastly different outside the US and the safety margin at 100 to 1 gets a bit slim.
myself I would stick with the 50 to 1.
 
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