1987 8 HP Yamaha Oil Mixture ?

[fishn4fn]

I just bought a used 1987 Mercury Mariner Outboard (made by Yamaha) motor that runs like a champ but I can't find the mixture ratio marked anywhere and I didn't get an owner's manual with it. Can anyone tell me the right mixture.
I have a 1988 5 hp Yamaha outboard that uses 100 to 1 mixture and my My Mariner was made by Yamaha (one of the reasons I bought it) but, I don't want to risk using too little oil mix in the gass. The ID plate is stamped with this model information:

Mariner 8M
6GI S 015503

Any help would be appreciated...

fishn4fn

 

[deejaycee_2000]

Re: 1987 8 HP Yamaha Oil Mixture ?

50:1 ............

 

[fishn4fn]

Re: 1987 8 HP Yamaha Oil Mixture ?

Came across an old Seloc Manual and it states 100 to 1. But thanks for the information even though it contradicts the Seloc Mariner Outboard tune-up and repair manual. Where did you come across the info that says 50 to 1?

I called an outbourd repair shop and they said 50 to 1 but they also said that for the one that I knew for a fact was 100 to 1. The guy told me that all two stroke motors used 50 to 1. Just shows you can't always trust the so-called experts.

I figured that the Mariner was the same as another Yamaha outboard that I own but wanted to be sure. My other Yamaha has 100 to 1 right on the motor but the Mariner didn't say anywhere that I could find. Looks like any two stroke mix would be printed right on the motor fuel intake as a rule. Only in a perfect world...

fishn4fn

 

[deejaycee_2000]

Re: 1987 8 HP Yamaha Oil Mixture ?

even if the motor (on the side) or the manual says 100:1, you must still mix it 50:1 ..... believe me ....

 

[fishn4fn]

Re: 1987 8 HP Yamaha Oil Mixture ?

Thanks deejaycee for the input but I have some other questions if you don't mind.

1. Why would I want to mix more than what the manual says? I have used the 5 hp for the last three years mixing 100:1 and it runs perfect. Am I wearing it out? Haven't even had to change an impeller on it since the first time. I used it at least twice a week every fishing season. It gets used in the river and used hard. It normally starts first pull. Been a real jewel since I put it back together. I also plan to use this 87 8hp Mariner just as much now that it is back together but I don't want to wear it out by not knowing as much as possible about using it properly.

2. What is the best oil to use? Been using penzoil 2 stroke.

3. Where is the best online place to buy Yamaha outboard parts? Been using boats.net.

Any insights are appreciated. This forum is just the ticket for an ameteur like me! Thanks all.

 

[hbradley]

Re: 1987 8 HP Yamaha Oil Mixture ?

always 50:1...50:1 always.

 

[mlafarge]

Re: 1987 8 HP Yamaha Oil Mixture ?

I would check with your Yamaha dealer. I have had several Yamaha 2 strokes and they used 100:1 mixture but only if you use Yamaha's oil which was called Yamalube other than using there oil it was highly recomend to use a 50:1 mixture of anyone elses oil..
Hope this helps Mlafarge