BajaNomad

Outboard motor question

woody with a view - 5-25-2013 at 03:22 PM

so i usually start the 25hp Mariner every other week and let it run for 10-15 minutes to keep the stale fuel fresh! last time i put new premium Pemex was 1 year ago. i'm getting a few small drops of oil off the prop after i shut it down (maybe a golfball size over the winter). i tried to run 50:1 but i know more is better than less oil so, maybe an extra splash.....

today it started on the second pull as usual, ran for 20 seconds and quit. choking it full it will run for a 10 seconds and die. i pulled the plugs and they are almost dripping with oil (DUH!) so i cleaned them, reinstalled and same situation.

i'm gonna get new fuel and plugs, but should i run a can of fuel system cleaner in it to remove all of the excess oil? any other tips? the fuel filter cup is see thru and looks clean.

Bomberro - 5-25-2013 at 04:18 PM

Sounds like the float could be stuck! Not uncommon, not too hard to r/r the float bowl and clean the float needle and seat, and the float pin. I always use exact 50/1 outboard 2 cycle oil. I have found its best for me to use fresh fuel every several months. There are two schools of thought on storing an outboard for a long time. One to drain float chamber, run motor out of fuel and spray some oil mist into spark plug hole. Other is to leave fuel in carb and run every so often so fuel does not dry up, the dried up fuel leaves lots of residues and can clog things up in the carb. Good luck!

monoloco - 5-25-2013 at 04:28 PM

You are better off draining every bit of fuel out of the motor and the tank when you store it, I do it to my motors unless I'm planning on using them within the next week or so, and have had them fire right up after storing them for over a year. The fuel in the tank will go bad fairly fast. There is a screw on the bottom of the float bowl that you can open to drain the carb before you store it. If you have problems due to varnish in the carburetor, it's best to take it apart and clean out all the jets and passages with spray carburetor cleaner, the carbs on outboards are very simple and it's a quick and easy process. There is never any reason to go higher than 50:1 on the oil mix, if you do you'll just foul plugs.

chuckie - 5-25-2013 at 04:46 PM

And the motor will run hotter with excess oil....NEVER store a motor without draining the carbs..NEVER...And get rid of any old gas...give it to someone you dont like very much....

rts551 - 5-25-2013 at 05:05 PM

I was told to always drain a 2-stroke (and use new fuel) but not to drain a four stroke (but use fuel stabilizer). He stated the 4-stroke carb is different and the seals will dry up and rot. Just passing the message since I have a 2-stroke.

monoloco - 5-25-2013 at 05:34 PM

Quote:
Originally posted by rts551
I was told to always drain a 2-stroke (and use new fuel) but not to drain a four stroke (but use fuel stabilizer). He stated the 4-stroke carb is different and the seals will dry up and rot. Just passing the message since I have a 2-stroke.
I always drain my four stroke outboard motor, and the four stroke motors on generators, motorcycles and other tools with no problem. A carburetor is a carburetor, not much difference between a two and four stroke carburetor. If you store them with fuel in them, they are going to varnish up eventually, fuel stabilizer or not.

rts551 - 5-25-2013 at 05:43 PM

Just passing the message (and was not challenging your process or knowledge of carburetors) ...after a larger (150 hp) 4-stroke had carb problems. On our ATV's (Honda, Suzuki, and KTM) we do not drain the carbs and never have problems, but they seldom sit longer than a month. I can tell you this, the carburetor on our KTM is way more complicated and nothing like the carb on our 2-stroke.
Quote:
Originally posted by monoloco
Quote:
Originally posted by rts551
I was told to always drain a 2-stroke (and use new fuel) but not to drain a four stroke (but use fuel stabilizer). He stated the 4-stroke carb is different and the seals will dry up and rot. Just passing the message since I have a 2-stroke.
I always drain my four stroke outboard motor, and the four stroke motors on generators, motorcycles and other tools with no problem. A carburetor is a carburetor, not much difference between a two and four stroke carburetor. If you store them with fuel in them, they are going to varnish up eventually, fuel stabilizer or not.

55steve - 5-25-2013 at 07:10 PM

I never run my oil/fuel at 50:1 - that's the mfg mix at wide open throttle. I usually run 70:1 and even go as lean as 80:1 in lobster season.

I seldom run my boat wide open but when I do it's never more than 30 seconds or so.

No oil related failures in 40 years of 2 strokes....YMMV

woody with a view - 5-25-2013 at 09:29 PM

i always heard that 50:1 was ideal so the oil would lube, kinda like leaded gas. i'll report back tomorrow.

SFandH - 5-26-2013 at 12:37 AM

Quote:
Originally posted by woody with a view

today it started on the second pull as usual, ran for 20 seconds and quit. choking it full it will run for a 10 seconds and die.


My 40 hp Evinrude was doing the same thing. It started fine, but wouldn't keep running unless I goosed the choke. Take the choke off, it would die 10 or so seconds later.

I concluded that without the choke it was running too lean. And it was too lean because air was leaking into the fuel line and/or carbs someplace. I carefully tightened all the fittings and hose clamps along the fuel line from the tank to the carbs and rebuilt the carbs using gasket/goodie kits I ordered over the Inet.

Runs great now.

Udo - 5-26-2013 at 07:33 AM

Just my dos centavos worth:


In my chain saw, weed eater, pressure washer:
After using them, I empty the fuel tanks and run the engines until dry.Then put in fresh gas when needed again.

mulegemichael - 5-26-2013 at 07:41 AM

we took our 25hp honda 4 stroke to a lake smallmouth fishing this past week....this motor MAYBE has 20 hours on it and is around 2 yrs old....dumped it in the water, loaded our gear and took off....it would not get up on step and top speed was 16mph when usually we cruise at around 26mph...tried everything; trimming the motor up and down, rearranging gear from front to back...no luck.....so i took it to our mechanic guys and they tested the gas and said there was NO octane left...this is after sitting over the winter in the garage...NO octane!...it just went away..poof!...and i run the motor completely dry every fall before storing it....problem is the motor uses SO little gas that i never am able to run the tank dry and over time, even using stabil, the octane just disappears...the mechanic said to pour the gas into our car's gas tank and fill with new stuff...drained the carb and she took off like a jackrabbit!

woody with a view - 5-26-2013 at 07:43 AM

^^^kinda what i'm thinking^^^

only problem is what do i do with 1.5-2 gallons of 50:1 gasoline mix?

SFandH - 5-26-2013 at 07:56 AM

Quote:
Originally posted by woody with a view
^^^kinda what i'm thinking^^^

only problem is what do i do with 1.5-2 gallons of 50:1 gasoline mix?


Take it on the next trip to the SSSSS (seven sisters secret surf spot), collect some wood, maybe take some with you, and have a bonfire.

[Edited on 5-26-2013 by SFandH]

Barry A. - 5-26-2013 at 08:13 AM

Quote:
Originally posted by mulegemichael
we took our 25hp honda 4 stroke to a lake smallmouth fishing this past week....this motor MAYBE has 20 hours on it and is around 2 yrs old....dumped it in the water, loaded our gear and took off....it would not get up on step and top speed was 16mph when usually we cruise at around 26mph...tried everything; trimming the motor up and down, rearranging gear from front to back...no luck.....so i took it to our mechanic guys and they tested the gas and said there was NO octane left...this is after sitting over the winter in the garage...NO octane!...it just went away..poof!...and i run the motor completely dry every fall before storing it....problem is the motor uses SO little gas that i never am able to run the tank dry and over time, even using stabil, the octane just disappears...the mechanic said to pour the gas into our car's gas tank and fill with new stuff...drained the carb and she took off like a jackrabbit!


I had exactly the same experience with my 35hp Mercury 2-stroke which is 28 years old but with fairly low hours on it-------new gasolene works wonders. :light:

-----and, each fall I always dump my mixed old fuel into my Isuzu Trooper's gas tank, fill the tank with new gas, and never any problems that I am aware of.

Barry

Just burn it in your car..

neilm81301 - 5-26-2013 at 08:28 AM

We always used to drain our 2-stroke dirtbike mix and put it in the truck for the drive home - never more than 3 or 4 gallons - in those days, some guys were running 20:1.

Neil
Quote:
Originally posted by woody with a view
^^^kinda what i'm thinking^^^

only problem is what do i do with 1.5-2 gallons of 50:1 gasoline mix?

mulegemichael - 5-26-2013 at 08:54 AM

yeah woody, just dump it in your car tank...no problem!

woody with a view - 5-26-2013 at 10:35 AM

i ain't putting oil in my gas tank, yrros!!!

boe4fun - 5-26-2013 at 05:56 PM

Take it to a recycling center where they accept used oil, they'll take the mixed gas as well. Toodles kids.

chuckie - 5-26-2013 at 06:01 PM

Geez,just dump it somewhere, or put it in your truck....it will get so diluted you wont even notice.....

woody with a view - 5-26-2013 at 06:02 PM

:light: