115 Johnson v4 2000 trouble staying started oil/gas leak from exhaust

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JoeFo86

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Hey y'all,
ok here is the situation, I went to start my boat to warm it up, and a large cloud of white smoke plumed into the air, not abnormal, except it was not stopping and the motor sounded like it was rough idling. It ends up stalling out. After that I would continue to try and start with the same ending shaking spuddering stop. The cloud I created did have a blue tint, not all white. There seems to be oil gas mix leaking out from under the top thinking carbs draining from motor on tilt. Also in the water there is a nice slick. This slick is new and I haven't seen this before. Everything ran fine and now 5 days later this happens.
side note. I did have my plug loosen and took on water over the back, it filled the bildge and almost over took the oil tank. I drained the gas tank and put a external tank for now. I didn't drain the oil because it didn't seem milky. It ran fine on land and driving back to slip.
Picture 1 is that of the pooling of gas oil mix in 3 outta 4 of the carbs, water picture show large sheen.
 

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racerone

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??----You should drain the oil tank ASAP.-----If the system is injecting water it could be an EXPENSIVE event.
 
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Chris1956

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At least suck a qt off the bottom of the oil tank into a clear container. Water can build up in the oil tank as a result of condensation, so it is wise to do that anyway.

You are referring to the oil drops on the carb throats in picture 1? That doesn't look abnormal.

White smoke is usually steam. Steam is not normal, at least in the summer. Steam would be produced if water got into your cylinders, but usually it condenses and is hard to see. Common failure points that let water in on Mercs is the exhaust baffle/cover, and lower crank seals. Yamaha's have a tendency for the heads to rot thru, allowing water from the cooling passage into the cylinder. Not sure on Johnny's however.

The gas/oil in the water could be from the carbs. When tilted up, they do leak some fuel mix. I think you should run a 50::1 gas/oil mix in your fuel tank until you get this figured out.

Also, take a compression test. If compression is real low, maybe you have a crack in the block somewhere.
 
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JoeFo86

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Chris1956 said:
At least suck a qt off the bottom of the oil tank into a clear container. Water can build up in the oil tank as a result of condensation, so it is wise to do that anyway.

You are referring to the oil drops on the carb throats in picture 1? That doesn't look abnormal.

White smoke is usually steam. Steam is not normal, at least in the summer. Steam would be produced if water got into your cylinders, but usually it condenses and is hard to see. Common failure points that let water in on Mercs is the exhaust baffle/cover, and lower crank seals. Yamaha's have a tendency for the heads to rot thru, allowing water from the cooling passage into the cylinder. Not sure on Johnny's however.

The gas/oil in the water could be from the carbs. When tilted up, they do leak some fuel mix. I think you should run a 50::1 gas/oil mix in your fuel tank until you get this figured out.

Also, take a compression test. If compression is real low, maybe you have a crack in the block somewhere.
Click to expand...
Yeah carb throats, they filled the bottom of the cover with oil gas mix. I cleaned it all out. I know they may drain a bit.
The smoke was white with a blue tint( according to my wife) I saw white lol,
That oil gas in water was pouring outta my exhaust Everytime I went to start it would start bubbling up
I will try compression test.
 
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Chris1956

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Your fuel pump is vacuum operated. If the fuel pump diaphragm leaks, raw fuel gets into the crankcase, fouling the spark plugs, and eventually escaping into the water.

Mix up some 50::1 fuel mix, disconnect the fuel linns from the fuel pump (OMS Pump) and using the primer bulb keep the carbs full. That is you are now the fuel pump, and see if the fuel in the water issue goes away.
 
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JoeFo86

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Chris1956 said:
Your fuel pump is vacuum operated. If the fuel pump diaphragm leaks, raw fuel gets into the crankcase, fouling the spark plugs, and eventually escaping into the water.

Mix up some 50::1 fuel mix, disconnect the fuel linns from the fuel pump (OMS Pump) and using the primer bulb keep the carbs full. That is you are now the fuel pump, and see if the fuel in the water issue goes away.
Click to expand...
Ok will give it a shot
 
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JoeFo86

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Chris1956 said:
Your fuel pump is vacuum operated. If the fuel pump diaphragm leaks, raw fuel gets into the crankcase, fouling the spark plugs, and eventually escaping into the water.

Mix up some 50::1 fuel mix, disconnect the fuel linns from the fuel pump (OMS Pump) and using the primer bulb keep the carbs full. That is you are now the fuel pump, and see if the fuel in the water issue goes away.
Click to expand...
Sorry boat repair dumb is the fuel pump 1 or 2? Both have a good seal and not warped. In water is a gas oil mix so I was assuming that like a car with out a cat it dumps unburned fuel into exhaust and into water
 

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Chris1956

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You can replace the OMS pump, but it is a $500 part. Rebuild kits are avail at the maxrules site, for less. The vapor pump may be rebuilt for a few $.

However, I would recommend you find out what the issue is before pulling out your checkbook.
 
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racerone

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??----The VRO is operated by PRESSURE pulses.-----The VRO uses an air motor.----Failure of the fuel diaphragm does not always result in fuel going into the crankcase.-----Trouble shoot the fuel system.----Find the leaks.-----
 
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Chris1956

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OK, Racerone, if either of the OMS pump diaphragm fails, does the fuel leak into the crankcase? I would think it does, however I am not an expert. The OMS pump and the Vapor pump are powered by the crankcase pulses, so what protects the crankcase from the raw fuel, if the diaphragm fails? Just a question.
 
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JoeFo86

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Ok rebuild kit 200 bucks? Gonna try to run fuel line 50:1 to bypass the VPO or OMS whatever it's called see what happens
 
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Chris1956

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Running 50::1 gasoline to 2 cycle oil will run that motor fine....

Most of the OMS pumps fail on the oil side, I am told. If that happens, the fuel side will pump the 50::1 just fine. If not, you need something else to pump the fuel.
 
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JoeFo86

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I rebuilt the VRO and then got a no oil light. I check the oil level it's 1/2 way down not too low but filled back up. The engine runs but still has trouble with reving, I rev up and it stalls out. Still blowing too much smoke. Any ideas?
 
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racerone

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Yes----It is always the carburetors.----Might as well rebuild them.-------Or perhaps do some easy trouble shooting first.-----This motor should at least fire , bark and roar when cranking with key pushed in , does it ???
 
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