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Chapo

Yamaha 115 / 4 Stroke ?'s

12 posts in this topic

I recently bought a boat with an 02 Yamaha 115, 4 stroke. No manual with boat and previous boat owner had everything done by the marina. This is my first 4 stroke, the questions I have is:

What octane fuel is best to use?

What viscosity oil to use/would full synthetic be better?

What to use for the lower unit?

What has to be done for winterization?

Thanks for your help.

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Use non-oxy gas when possible

10w-30 Marine 4 stroke oil-High quality major brand

Marine Gear Lube-High quality major brand

To winterize, Stabalize the gas, change gear lube, engine oil and filter, fog engine, grease all zerks and drain the VST tank (vapor separator)

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Chapo....good questions! Pending the checkout at a dealer tomorrow I may also have an 02 Yamaha 115 4-stroke in my garage this weekend. My first boat so great timing on this post!

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I have a 03 Yamaha 115 4 Stroke and love it. I run Amsoil 4 stroke oil in it and their lower unit oil. I run Premium gas most of the time but I go through a lot of gas so regular unleaded is used often too. I just wouldnt run it all the time I guess.

If you dont like Amsoil than just run the Yamaha Oil.

When I winterize I put Stabil in the tank and run the boat for that last day out. I then change plugs and change filter and oil and lower unit lube. Make sure you drain all the water out of the boat and livewells and grease trailer and charge batteries up. I keep them in the boat in the garage and charge monthly. Take all graphs inside.

If you have mice around put dryer sheets in all storage.

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The VST is behind the intake manifold. There is a slotted drain screw at the bottom of it.

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Just do a search for Yamaha on the net, and you can download the exact manual you need, for free. I know because I did it this past fall when I got my new setup. I didn't print it out because it is like 80 pages, but I saved it on my laptop if I need to look at it. All of those questions are of course in the manual.

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Just do a search for Yamaha on the net, and you can download the exact manual you need, for free. I know because I did it this past fall when I got my new setup. I didn't print it out because it is like 80 pages, but I saved it on my laptop if I need to look at it. All of those questions are of course in the manual.

Just FYI... I don't think you can print these manuals. Something in the PDF that won't allow it. But yes, you can download them and save the electronic copy on your PC.

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I know there have been other posts, but how much harm will using a non-marine synthetic oil in a four stroke cause? Can Mobile 1 sythetic be used safely in a Yamaha f150?

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I would go with what's recommended. Its cheaper than a new motor. (I also agree with marine_man

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