Smoking outboard 1998 mercury 6 hp 2 stroke. Fuel/oil mix is 100 to 1, the engine smokes bad in all throttle ranges. Is the fuel mix wrong or are the rings bad ? thanks

https://www.google.com/search?q=1957+johnson+outboard+10+hp+fuel+oil+ratio

What is the mix ratio for a Johnson outboard motor?

Any Johnson outboard motor built since 1964 requires a 50/1 fuel ratio. Motors built prior to that date require a 32/1 ratio, with the exception of a few fishing motors built prior to 1955 that use a 16/1 ratio.

Feb. 22, 2021

What is the mixing ratio for a Johnson outboard motor? - Mvorganizing.org

assuming this is a 2 stroke small engine, smoking is a sign of wrong oil / fuel mix
add to that it the oil mix is wrong, the jets in the carby have trouble passing the fuel easily so there will be a choking problem
It is a 4 stroke , take it back for a warranty check and adjustment

need the year of manufacture as some 2 stroke units have oil injection that automatically mixes the oil in the correct ratio for engine rpms otherwise it is 50:1 ( 50 parts fuel to 1 part oil)
oil requirements --certified tc-w3 2 stroke outboard oil ---not ordinary engine oil
reference
google --type in mercury outboard oil to fuel ratio

Peter
you are too short on details like make model , 2 stroke or 4 stroke
read your user manual or look on the petrol cap as most have the ratio on the bowser emblem
so for an answer, it is most likely a 2 stroke and so-- yes-- it will require a oil/fuel mix in the tank
if you do not know it , start with a ratio of 40:1 ( 40 fuel -1 oil) and only use 2 stroke oil not normal engine oil
run at rpms and there should be a trace of blue smoke
too much smoke cut the oil back to 50:1 and no smoke increase the oil to 30:1
go google and type in user manual for ( make and model ) --and the ratio will be in that print put

Sorry... Earl Soderlund,

The first thing that comes to mind... (without any SPECIFICS
from you, make, model, year... etc.)... is the two cycle syndrome...

4 cycle engines generally have their own crank-case-oil and can run with untreated gasoline...

2 cycle engines need 2 CYCLE OIL to be MIXED with their fuel...!!!

Some folks see an engine... put in GASOLINE and expect it should run.

The most common outcome is friction heat causes heat, abrupt stop... and a COOL DOWN period... before these ENGINE DAMAGE cycles can resume.

Each occasion DOES INDEED damage the engine.

Include the make & model...

or better yet look it up yourself on the internet... COMBINED with the TWO-CYCLE oil MIXTURE recommendation...

You engine can then be tuned and adjusted and give years of happy service.

Hope this helped.

Amazon com Husqvarna 2 6 oz Low Smoke Formula 2 Cycle Engine Oil 6 Pack...


Amazon com 2 cycle boat motor


2005 Mercury 50 HP 2 cycle 3 cylinder Outboard Trim Tilt Motor

50:1 But if your doing mostly low rpm cruising (trolling) then you could reduce that a bit to 75:1 to help reduce smoke. If you do mostly mid to higher rpm cruising, then 50:1 (1 pint to 6 gallons. )
Or 200mls in 20 liters if your Canadian.

If your old engine/control has the same 'options' as the30hp, yes everything is compatible... (Electric start or trim )
The throttle and shift cables are allways compatible...

2 cycle, 50:1

Fuel mix is likely, ensure manufactures specs are followed when mixing. Most modern 2 stroke outboard engines run on 100 to 1 mix, unlike older ones that ran on 50 or 33 to 1.

Cheers, Timo.