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1995 90HP Johnson Outboard starts runs rough then dies. Water fouling on two plugs

turk

New member
I had water in the fuel but I believe I got it all out. Seems to be good fuel coming out now. Also changed the fuel/water seperator. Two of the spark plugs are still fouling with a white liquid, I assume it is still water in the fuel? Perhaps a leak in the water jacket gasket? However the two cylinders that are still fouling the spark plugs are on seperate heads. Also seems to be a white/greyish gumming substance on top of the pistons in the two that are still fouling.

Any Suggestions? Any help would be greatly appreciated!

P.S engine model is J90TLEOR​
 
you may still have contamination in the tank or hose etc......try a new tank with a new hose and bulb......add some sea foam....did you clean or change the little screen filter under the cowl? ......if the motor still dies then tilt the engine till just enough of the lower unit is in the water for the water pump to do its job......if the motor runs like that and dies tilted down then you have water in the carbs....if it runs like that then run it tilted for a good while and then slowly tilt it down a little at a time until you are able to run it in the run position...you probably should pull the carbs and clean them...
 
1 and 2 are fed by the top carburetor and 3 and 4 are fed by the lower carburetor.--Have you checked the oil tank ( if used ) for water in it.---Does the motor show any signs of major repair ?? ----This could also be an internal leak straight from the main water passage into the crankcase.
 
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After thinking about it some more I think it may be a few things. First I did try a different hose with new fuel and it ran good. When I hooked it back up to the installed tank it didn't start...this is what pointed me to water in the fuel. So I pump out almost 12 gallons and also put in 5 or six gallons of good fuel and also a can of sea foam. Fuel coming out seems like it is good now (Actually smells like gas) Also it is interesting that 1 and 2 are fed by the top carb while 3 and 4 are fed by the bottom. I open the top carbs drain to see if there was any more water in it and there was so I let it drain. I have not drained the bottom one yet which makes me think I should as it is cylinder 3 and 4 that has white liquid on the plugs however 1 and 2 do not. I think I may also check the manual prmier valve in case it was opened....it seems cylinders 1 and 2 spark plugs are wet but looks to be gas. Anyway thanks for your suggestions, shoul dbe a big help. one more thing...after trying to get it to run from the installed fuel tank I tried once again with fresh gas from another tank and although it ran it still died...pulled the plugs and found they were fouled again.
 
At this point I suggest a compression test.------------" fouled " plugs may be an indication of " cold running " cylinders.-----Plugs foul for a reason, some are ---weak spark----poor compression ---too much fuel---no thermostats.
 
Yes I plan on doing a compession test. Have another question, this may be silly but can't seem to find any info on it. When I prime the fuel line (With the primer bulb) I often hear a click. Is this click something in the carbs...I also hear the same click after the engine is sitting for awhile after I tried starting it? Any thoughts?
 
The VRO pump will click when motor is running.----Caused by the air motor cycling in the pump.----Has anyone inspected the operation of the pump.---Various repair kits are available for them.------------Click could be caused by leaking check valves on the air motor piston housing.
 
I don't think it would be the pump as I am getting to much fuel (Unless the pump is pumping to much)...but I will certainly have that check. The clicking I here is when I am squeezing the primer bulb on the fuel line. It is only one click, sounds almost like something "springing" into position.
 
agree with everything racer said and will leave the motor area to him...i will concentrate on the fuel supply...your built in fuel tank has contamination....it will have to be cleaned out if you continue to use it....i would also install a water separator in the fuel line when all is said and done...is the tank aluminum?...every gas hose both external and internal is suspect to have the same white and grey stuff you described...fuel pump also...carbs too...sounds like separation caused by ethanol that has been set up too long... you said it ran good with a new tank and hose and then you hooked the built in tank back up and it failed.....i would suspect that you picked up more crud again..
 
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