fuel on water 1980 25hp

fmalott · Aug 4, 2010

i have a 1980 25hp johnson i posted other things when rebuilding carb
got motor running excellent
cleaned high speed jet with wire blew out with air replaced needle and seat starts great no problems just one thing went fishing put throttle to floor ran great started to troll at low speed motor ran great caught a fish put in nuetral to bring in fish i noticed there was fuel on the water not a whole lot but enough to notice is this normal or do i have to adjust something more
the low speed i turned out 1 1/2 turns, fuel 50:1 what else should i look at

Daviet · Aug 4, 2010

Re: fuel on water 1980 25hp

2 cycle outboards are not really fuel efficient, all the fuel does not get completely burnt in the cylinder. You might try adjusting the low speed jet in a little after the engine is warmed up, but to see a little fuel on the water is not uncommon.

Rscardina · Aug 4, 2010

Re: fuel on water 1980 25hp

I thought the song was "smoke on the water"..not fuel on the water...

Ok so its not that funny, but I think Daviet is correct on this one. If your idle was so off to suggest fuel spilling..I would think you would have noticed a huge amount of smoke..more than previous...and you would definitely feel the bogging

If its not smoking or bogging more...then I say you are probably ok..

jtexas · Aug 4, 2010

Re: fuel on water 1980 25hp

No, it's not normal to see gasoline on the water. "not normal" in the sense that, "fuel discharge into the lake" is not a "design feature" of the motor. Clearly it's not uncommon, and the motor can continue to operate normally while leaking gas. And there's no tree-hugging environazi's here, those guys aren't even allowed to own 2-stroke outboards. Still, that doesn't mean you'd necessarily want to pour gasoline overboard...that stuff is way too expensive.

I'm sure these guys are right, it's unlikely to be so rich that fuel is pooring out the exhaust. So, inspect all the fuel line and connections from pump to carbs, while the motors running, and again motor off while you (or a helper) squeeze the primer bulb. Around the fuel pump, carb mounting gaskets.

See if oil is collecting on the floor inside the cowling under the air silencer. Or anywhere else, and trace it to its source. There's a hose between the manifold and bypass cover, and one between manifold and crankcase. And the air silencer gasket.

Watch for unburnt engine oil dripping from the exhaust after running the motor for awhile; if you see it, check out the "Decarb" thread over in the "Engine FAQ" section of iboats. Even if you don't see it, read the thread anyway, it's good stuff.

Carusoswi · Aug 4, 2010

Re: fuel on water 1980 25hp

. . . check your internal fuel lines. This happened to me once. Fuel was collecting inside the housing and making quite a mess on the water. Problem was a rotted hose that runs under the cover, from the fuel hose connector to the carb. I snipped it to eliminate the bad portion of hose, reconnected the hose, end of problem.

Hope your problem turns out to be so simple.

Caruso

fmalott · Aug 4, 2010

Re: fuel on water 1980 25hp

i will check all fuel lines and so on and i will recheck low speed idle, fuel pump is good put on brand new when rebuilt carb thanks guys

fmalott · Aug 6, 2010

Re: fuel on water 1980 25hp

there was more smoke from engine than before but no bogging, but it's running great so should i just tinker with low speed idle, there is only fuel on water when motor is running. lots a smoke happened many years ago i changed fuel ratio to 25:1 this stopped the smoke and engine ran great for years up until this year, as mentioned before rebuilt carb now runs good again but fuel on water and lots of smoke should i go back to 25:1 and adjust low speed idle

Rscardina · Aug 6, 2010

Re: fuel on water 1980 25hp

fmalott said:
there was more smoke from engine than before but no bogging, but it's running great so should i just tinker with low speed idle, there is only fuel on water when motor is running. lots a smoke happened many years ago i changed fuel ratio to 25:1 this stopped the smoke and engine ran great for years up until this year, as mentioned before rebuilt carb now runs good again but fuel on water and lots of smoke should i go back to 25:1 and adjust low speed idle

does that have a VRO??.. if so ..you may have an air leak...in the fuel line..

fmalott · Aug 6, 2010

Re: fuel on water 1980 25hp

sorry i don't know what VRO means i'm not a mechanic just a bark yard guy being on this site i'm starting to learn some short hand more and more i never heard of VRO

Daviet · Aug 6, 2010

Re: fuel on water 1980 25hp

You should be running a 50:1, if you are running 25:1, you should have more smoke than 50:1 ratio.

fmalott · Aug 6, 2010

Re: fuel on water 1980 25hp

right know i'm running 50:1 with smoke did i say it backwards when saying 50:1
i did not put as much mix with fuel i put 1/2 what they asked for 50:1

Daviet · Aug 6, 2010

Re: fuel on water 1980 25hp

If you put 1/2 pint of oil for 6 gal of gas, you are to lean on oil. You need to add 1 pint of oil to 6 gal of gas.
25:1 would be about 1 quart of oil to 6 gal of gas, way to much oil for your engine.

fmalott · Aug 7, 2010

Re: fuel on water 1980 25hp

i'm canadian so what i was doing for 15years with this motor was 200ml oil to 25litres gas which is what Daviet said 1/2 pint to 6.6 gal and it ran excellent up to this year cleaned carbs mixed 1pint oil to 6.6gal gas got alot of smoke and fuel on water when boat was running but still ran good
so i'm stuck between a rock and a hard place put 1/2 pint to 6.6gal ran great with no smoke or fuel on water now i put 1pint to 6.6gal got smoke and fuel on water whats the pros and cons on using 1/2 pint to 1 pint

fmalott · Aug 7, 2010

Re: fuel on water 1980 25hp

bump

Al-53 · Aug 7, 2010

Re: fuel on water 1980 25hp

running a lean oil mix (100:1) may cause pre-mature engine wear.....run the 50:1 ratio as reccomended by OMC.....

not all the oil burns in the combustion chamber so you do get a little oil in the exhaust....

if you want a little less smoke try using a synthetic oil....like the pennz oil brand...it is also biodegradable..I run XD-50 in my 1983 35hp and have no smoke...and hardly any water ring from exhaust....

also if you troll alot..you may want to go to the next hotter plug..I do not know which one it is..but have seen it referenced here a few times....

also do a de-carb on the motor to get excess carbon out of the motor..it may help...

Al

fmalott · Aug 7, 2010

Re: fuel on water 1980 25hp

so use a synthetic oil sounds like a solution i will give it a try this week going to cottage for 1 week do you think adjusting low speed idle a liitle more might help as i rebult carb turned low speed 1 1/2 turns out it seems fine there do you think in more or out more

jasper60103 · Aug 7, 2010

Re: fuel on water 1980 25hp

fmalott,
I have the same motor, a '81 j25hp. I run 50:1 using regular TCW3 oil. I ran my motor in a bucket just last Thursday and saw no excessive amount of fuel in the water, but I was only running idle. Maybe just a slight rainbow.
Anyway, I dumped a good portion of the 30 gallons of water on my lawn. I can't say why you're seeing fuel, but I would give the synthetic a try as recommended, especially since your engine is running good. You have nothing to loose.
Also, I checked my OMC factory manual and the initial low speed needle setting is 3/4 turns out (1-1/4 for the 35 hp model). Again, this is just the initial setting, you adjust until you find the highest RPM and smoothest idle. Again, check your fuel lines for leaks as recommended.

edit:
after thinking about it. I would just follow the joe reeves carb adjustment procedure, which is where you're initial carb setting is at.
http://forums.iboats.com/showthread.php?t=167352

jasper

fmalott · Aug 7, 2010

Re: fuel on water 1980 25hp

ok i will try 3/4 turn see what happens it's still a good diffrence from 1 1/2 turns
i will post when i get back from holidays

jtexas · Aug 8, 2010

Re: fuel on water 1980 25hp

Stop guessing at the slow speed needle setting, read & follow Joe Reeves' instructions here: http://forums.iboats.com/showthread.php?t=167352

100:1 (1/2 pint per 6 gal) is fine if all you do is idle, otherwise you're going to burn that motor up prematurely.

Once again, if you're leaving a trail of gas behind your boat, you got a leak somewhere. It's not normal.

fuel on water 1980 25hp

Chief Petty Officer

Fleet Admiral

Chief Petty Officer

Fleet Admiral

Seaman Apprentice

Chief Petty Officer

Chief Petty Officer

Chief Petty Officer

Chief Petty Officer

Fleet Admiral

Chief Petty Officer

Fleet Admiral

Chief Petty Officer

Chief Petty Officer

Chief Petty Officer

Chief Petty Officer

Commander

Chief Petty Officer

Fleet Admiral