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New Yamaha 115HP Saltwater Series

Printed From: The Fishing Website
Category: General Forums
Forum Name: The Outboard Clinic
Forum Description: Anything related to outboard maintenance here....
URL: https://www.fishing.net.nz/forum/forum_posts.asp?TID=112316
Printed Date: 29 May 2026 at 6:17am


Topic: New Yamaha 115HP Saltwater Series
Posted By: stone2
Subject: New Yamaha 115HP Saltwater Series
Date Posted: 17 Sep 2015 at 10:25pm
Hi, Am going to get one of these for a 5.2m glass boat. I'm in west Auckland so want to buy locally for service reasons.
 http://www.bensemann.co.nz/index.php/2014-07-24-03-18-01/outboards/two-stroke-outboards/product/316-yamaha-115hp-115cetol
They also suggested a 90HP Yammy would be fine as well but I would like a little extra for skiing and diving.

Is there anything I should know about this engine and or the dealer? Am going to have them fit it as well.

The current motor is a Evinrude V4 1894 or 89 90HP that overheated last summer. Head gasket I think as water in one of the cylinders. I was offered a couple of hundred bucks for the old motor from the dealer. Would I get more for it on tradme perhaps?



Replies:
Posted By: CoastalStan
Date Posted: 17 Sep 2015 at 10:46pm
Great engines but always run it on 98 if you can. Make sure you have a good filter as they don't like water in the carbs. Always flush for at least 10 mins as the thermostat doesn't open for at least 5 mins. They don't like stale fuel.


Posted By: lemmy
Date Posted: 18 Sep 2015 at 5:37am
I got a 90 Yammy of the Team at Benseman a few months ago could,nt fault the job they did great guys to deal with.



Posted By: Muzzfishing
Date Posted: 18 Sep 2015 at 6:53pm
Originally posted by CoastalStan CoastalStan wrote:

Great engines but always run it on 98 if you can. Make sure you have a good filter as they don't like water in the carbs. Always flush for at least 10 mins as the thermostat doesn't open for at least 5 mins. They don't like stale fuel.
Just curious as to why you say run on 98 octane fuel is there any advantages over running 91fuel.


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http://www.legasea.co.nz" rel="nofollow">     A Good Skipper Keeps the water on the outside of the boat.


Posted By: CoastalStan
Date Posted: 18 Sep 2015 at 7:23pm
I had a few issues with the first one I owned, gradually got harder to start and occasionally would just got Barrrrrrr when you gassed it. Drained the fuel and cleaned out the carbs and all good for a while. Mechanic advised me to stop running it on 91 and change to 95 and 98 if possible. Once I change to 98 never had a problem. Didn't notice any change to $ per mile and if you didn't use it for a couple of months it started first pop and ran like a dream. I think his theory was that the octane rating drops as it gets older, better to start with 98 and it drops to 93 that 91 dropping to 86. I don't know exactly but it reduced my maintenance costs and ran much better.


Posted By: Muzzfishing
Date Posted: 18 Sep 2015 at 7:30pm
Originally posted by CoastalStan CoastalStan wrote:

I had a few issues with the first one I owned, gradually got harder to start and occasionally would just got Barrrrrrr when you gassed it. Drained the fuel and cleaned out the carbs and all good for a while. Mechanic advised me to stop running it on 91 and change to 95 and 98 if possible. Once I change to 98 never had a problem. Didn't notice any change to $ per mile and if you didn't use it for a couple of months it started first pop and ran like a dream. I think his theory was that the octane rating drops as it gets older, better to start with 98 and it drops to 93 that 91 dropping to 86. I don't know exactly but it reduced my maintenance costs and ran much better.
 
Thanks I have read some where that if leaving petrol in tanks for long periods its better to leave a higher octane petrol than lower octane petrol. 


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http://www.legasea.co.nz" rel="nofollow">     A Good Skipper Keeps the water on the outside of the boat.


Posted By: MacSkipper
Date Posted: 19 Sep 2015 at 5:59am
Originally posted by Muzzfishing Muzzfishing wrote:

Originally posted by CoastalStan CoastalStan wrote:

Great engines but always run it on 98 if you can.
Just curious as to why you say run on 98 octane fuel is there any advantages over running 91fuel.
I am not exactly sure as why higher Octane rating is better as Octane is an anti knock rating not to do with volatiles as such in fuel - but my mechanic said same thing - when I asked him why he said is a better quality fuel and he has seen it fouls plugs less on my Mercury 50hp 2S. 


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Good fishing trip nothing breaks, great trip catch fish.


Posted By: Grasshoppa
Date Posted: 19 Sep 2015 at 7:14am
When i done my time, i was taught that yes,Octane , is basically a anti-knock index or rating (amongst some other things)
Pre-ignition or detonation which is absolutely terminal to 2 stroke engines is caused by either too high compression, too much spark advance or poor quality/therefore lower rated fuel.
In the first case, the higher the octane rating of the fuel you have sitting in your tank slowly deteriorating, the more "octane" it has to lose the longer it has before its "stale" enough to potentially cause a problem.
If you think the boat may sit unused for any period of time either completely fill the tank (no or less space for the volatile 'light ends" to evaporate off too), or completely empty so less fuel to get to stale stage.
When boat is used first time, fill tank with highest grade you can to mix with old and give a better average octane rating across current and new fuel.
If boats been used daily and engine is rated for 91 its ok too as your getting thru the fuel before it can go stale, bit more affordable for some doing this

Dont mean to sidetrack but i'll get on my soapbox here and have a crack at those who bleat on this forum about mechanics/costs of servicing and how they purchased sparkplugs and a filter and done the "service" themselves, its basic fundamentals like understanding why different fuels (other than just "cos my mate said i should") amongst other things.

Its not only what a trained service tech does, but hopefully what they see/recognize and resolve before its an issue that lets them charge a hopefully only modest fee
Rant over, sorry

Fouling is often caused by the additives used to boost a fuels rating, good old lead was a vastly superior fuel which lasted much longer, if you can get aviation fuel at a decent price thats the way to go, but is usually prohibitively expensive
Pity the yanks who get ethanol in a lot of their full (as do Gull here), that stuff melts certain plastics/rubbers etc and they have dissolving fuelines etc to deal with, not as much a problem as before but something else they have to deal with



Posted By: Grasshoppa
Date Posted: 19 Sep 2015 at 7:16am
oh yeah, the outboard your considering is a great engineSmile


Posted By: MacSkipper
Date Posted: 19 Sep 2015 at 7:24am
Originally posted by Grasshoppa Grasshoppa wrote:

When i done my time, i was taught that yes,Octane , is basically a anti-knock index or rating (amongst some other things)
Pre-ignition or detonation which is absolutely terminal to 2 stroke engines is caused by either too high compression, too much spark advance or poor quality/therefore lower rated fuel.
In the first case, the higher the octane rating of the fuel you have sitting in your tank slowly deteriorating, the more "octane" it has to lose the longer it has before its "stale" enough to potentially cause a problem.
If you think the boat may sit unused for any period of time either completely fill the tank (no or less space for the volatile 'light ends" to evaporate off too), or completely empty so less fuel to get to stale stage.
When boat is used first time, fill tank with highest grade you can to mix with old and give a better average octane rating across current and new fuel.
If boats been used daily and engine is rated for 91 its ok too as your getting thru the fuel before it can go stale, bit more affordable for some doing this

Dont mean to sidetrack but i'll get on my soapbox here and have a crack at those who bleat on this forum about mechanics/costs of servicing and how they purchased sparkplugs and a filter and done the "service" themselves, its basic fundamentals like understanding why different fuels (other than just "cos my mate said i should") amongst other things.

Its not only what a trained service tech does, but hopefully what they see/recognize and resolve before its an issue that lets them charge a hopefully only modest fee
Rant over, sorry

Fouling is often caused by the additives used to boost a fuels rating, good old lead was a vastly superior fuel which lasted much longer, if you can get aviation fuel at a decent price thats the way to go, but is usually prohibitively expensive
Pity the yanks who get ethanol in a lot of their full (as do Gull here), that stuff melts certain plastics/rubbers etc and they have dissolving fuelines etc to deal with, not as much a problem as before but something else they have to deal with

Thanks Grasshoppa makes a lot of sense Clap.


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Good fishing trip nothing breaks, great trip catch fish.


Posted By: stone2
Date Posted: 19 Sep 2015 at 8:23pm
thanks for all the great advice people. Feel better now. Big smile



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