Never too much oil?

kvan64

Seaman Apprentice
Joined
Mar 2, 2008
Messages
48
Hi, the owner's manual of my 40HP 2006 2stroke Yamaha recommended a 100:1 mix after the break-in period. My backyard mechanic neighbor recommended 50:1 and also remarked:"Never too much oil. It protects your motor. Just change the spark plug more often". What do you think?

Also is it ok for 2stroke yammies to have some white smoke at cold start? It goes away after a few minutes and no smoke is spotted when on water.

Also how loud is considered to be loud for a 2 stroke motor?
 

rodbolt

Supreme Mariner
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Sep 1, 2003
Messages
20,066
Re: Never too much oil?

2 stroked carbed and EFI motors smoke at cold start, its just a fact of life, how loud is to loud is like asking how high is high.
your 40 will work well at 100/1. however if a lean out or minor overheat occurs its not enough. the other reason we tend to go with the 50/1 is lack of use .
most folks wont winterize the engines for extended(over 30 days) storage and lack of residual oil allows the shiny parts inside the engine to rust.
so if you promise to take proper care of the engine subsystems and take proper precautions if its going to sit over 30 days yes 100/1 is ok, if not stick with 50/1. you wont see any difference in plug fouling.
 

kvan64

Seaman Apprentice
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Mar 2, 2008
Messages
48
Re: Never too much oil?

Thanks Rodbolt for clarification of my wonderings. In regarding to the question about "how loud is loud" for 2 strokies, I was thinking of a scale in decibels. I asked this question because my neighbor was giving a weird look when I flushed my outboard on muffs in late afternoons. I was wondering if just my 2stroke is loud or if they all are loud that way.
 

mpsyamaha

Chief Petty Officer
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Jun 8, 2007
Messages
400
Re: Never too much oil?

all 2 strokes are loud out of the water... and the 4 strokes arent real quiet either. the water is the muffler.
 

Silvertip

Supreme Mariner
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Sep 22, 2003
Messages
28,771
Re: Never too much oil?

On a dB scale most outboards (at least midrange HP), two stroke or four stroke measure in the very high 80 dB range (87 - 89 dB to be more precise).
 

Lundman

Petty Officer 2nd Class
Joined
Sep 25, 2006
Messages
142
Re: Never too much oil?

I am,and always have been,a bit skeptical of Yamaha only requiring a 100:1
gas/oil mix. This does not seem like quite enough oil for a two stroke. My Merc
required a 50:1 mix. and that was well enough oil for it. If your Yamaha was MY motor,I would run it on a 50:1 mix.
 

Captain Paul

Petty Officer 2nd Class
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Jul 31, 2005
Messages
143
Re: Never too much oil?

As far as noise, I've never run a db meter on my 150, but it's got a bark on the muffs, they all do. Put it in a can if it's too much, that really works.
 

sc_shane

Petty Officer 2nd Class
Joined
Mar 1, 2007
Messages
167
Re: Never too much oil?

For reference on the decibels you can be pretty safe in saying your outboard (at say 1250 - 1750 rpms) on muffs should be about as loud as an average lawn mower at mowing throttle. Generally speaking, a lawnmower is about 90db.
 

kvan64

Seaman Apprentice
Joined
Mar 2, 2008
Messages
48
Re: Never too much oil?

As far as noise, I've never run a db meter on my 150, but it's got a bark on the muffs, they all do. Put it in a can if it's too much, that really works.

Does it really work? you must have a really big "can" :)
 

Captain Paul

Petty Officer 2nd Class
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Jul 31, 2005
Messages
143
Re: Never too much oil?

ummmm....I should have clarified....Garbage Can
 

Scout Sport Fish

Petty Officer 2nd Class
Joined
Apr 23, 2007
Messages
197
Re: Never too much oil?

I rember my first time starting my 2 stroke 130 up when I was 12 with muffs on it I almost jumped off my boat and broke my ankle!
 

kvan64

Seaman Apprentice
Joined
Mar 2, 2008
Messages
48
Re: Never too much oil?

Haha Scout, ...my nephew almost jump out and broke his ankle this arvo when I pulled the throttle :)

Well guys, I have a ratio of 50:1 in my current tanks. Have to admit that it seems to smoke a bit more compare to 100:1

If it keeps smoking 15 minutes after starting (visible but not excessively), is there something wrong with it? I don't seem to see any smoke after running for a while in water.
 

Yamajoe

Petty Officer 1st Class
Joined
Oct 31, 2007
Messages
264
Re: Never too much oil?

For some reason the 40hp 2 cyl kicks out a bit of noise, certainly more than my 60 3 cyl, but it does have great power, i have no complaints, love that noise and dig that smell of burnt gas an oil.
 

pine island fred

Lieutenant Junior Grade
Joined
Dec 20, 2002
Messages
1,144
Re: Never too much oil?

If you are in a boating community, neighbors should expect to hear you flushing up until sundown. I flush my 3 cyl merc at idle only for about 5 mins. max. If a neighbor complains, have them be around when their lawn service run their weed wackers and leaf blowers, now there is some aggraviting noise. FRED
 

kvan64

Seaman Apprentice
Joined
Mar 2, 2008
Messages
48
Re: Never too much oil?

For some reason the 40hp 2 cyl kicks out a bit of noise, certainly more than my 60 3 cyl, but it does have great power, i have no complaints, love that noise and dig that smell of burnt gas an oil.

Yamajoe, it sounds like you know this motor. Do you know the American model name/number of this? My is Australian and has the model number 40XWT and I can't find/buy a service manual here in Australia (have checked with many marinas/boat shops). I just hope that I could match it with an equivalent American or European model number so that I could find a similar service manual.
 

kvan64

Seaman Apprentice
Joined
Mar 2, 2008
Messages
48
Re: Never too much oil?

Yeah, that's the one. At least if tells me the part numbers so that I could order the correct parts for it. Hope that someone could help me find/buy the service manual for this motor. Thanks for the reply/information. Much appreciated. DK
 
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