Johnson 50 hp suspect water entering bottom cylinder.

[bagnallt]

Hi guys... My 1972 johnson 50hp is giving me more problems.
After all the help As many know I have replaced the stater flywheel coils etc.
I did have a small problem of what looked like unburned gas coming out the hub. but this cleared.
Anyway heres my new problem. Out on the water 3 days ago the motor ran like a dream.. Pushing the boat at over 25 mph not even at wot. Ran great. ok took the boat out yesterday. Idled away from the ramp.. down the lake a little to make sure nice and warm.. My wife pushed the throttle it wouldnt run above 8 0r 9 mph you could tell it was running on one cylinder. When I got home check the spark plugs and found the bottom cylinder spark plug was clean .. obviously water getting into the cylinder. Ok. I know it didnt overheat previously and i know it didnt overheat yesterday. Is it more likely to be the cylinder head gasket??
I am awaiting my workshop manual .. good old Amazon.com sent me the wrong one... before i replace the gasket.
If its the exhaust gaskets they are at the side of the engine yep? and do you have to pull the powerhead to remove the bottom bolts or is ther away to remove the lower parts of the shroud??? to access the lower bolts.. I am asuming they must be a 2 inches in lenght and the bottom bolts have a cleaance of about a 1/2 inch.. ...
Thanks for your help

 

[ezeke]

Re: Johnson 50 hp suspect water entering bottom cylinder.

It is still more likely to be the head gasket. Keep the cylinders extra well oiled while you troubleshoot the engine, and try not to leave it tilted up.

 

[tashasdaddy]

Re: Johnson 50 hp suspect water entering bottom cylinder.

put some oil in the bottom cylinder, and turn the motor over with plug out. watch out for spray. get oil back on the metal, so it doesn't rust up.

 

[bagnallt]

Re: Johnson 50 hp suspect water entering bottom cylinder.

Hi guys...
Quick update .. I checked the motor and gave it a quick turn over with the bottom plug out .. on muffs... It sprayed gas ( premix) out like no tomorrow.
SO i though great... I put the plug back in and low and behold.. out of the exhaust through the prop.. white frothy unburn fuel as before which i was told was water getting into the cylinder casuing the cylinder not to fire and the gas was pumped out in the exhuast. . I thought i had water going into the cylinder causing it it not to fire.. hence it was only running on one cyclinder on the water. However .. I checked the bottom plug again and not a hint of water.... I was at a loss as to what it could be.. SO I checked everything I had done.. And ( boy do i feel stupid ) I checked the carb and the idle screw was so far out it was flooding the cylinder. Mr stupid here had forgotton to screw the idle screw in to the correct setting and the motor was just running on the top cylinder becasue i had adjusted tha carb idle screw.
So we finally got out on the water today and boat flew.. straight up to 26 mph not even at WOT. My wife was overjoyed she had the boat flying along.. and though t had enough power left to easily brake 30mph.
The only thing we had was a rough idle and cut out but that was becasue i need to ajust the low end throttle... but thats an easy fix...
Thanks for all your help!! And happy easter to you all

 

[bagnallt]

Re: Johnson 50 hp suspect water entering bottom cylinder.

Hi guys...
Quick update .. I checked the motor and gave it a quick turn over with the bottom plug out .. on muffs... It sprayed gas ( premix) out like no tomorrow.
SO i though great... I put the plug back in and low and behold.. out of the exhaust through the prop.. white frothy unburn fuel as before which i was told was water getting into the cylinder casuing the cylinder not to fire and the gas was pumped out in the exhuast. . I thought i had water going into the cylinder causing it it not to fire.. hence it was only running on one cyclinder on the water. However .. I checked the bottom plug again and not a hint of water.... I was at a loss as to what it could be.. SO I checked everything I had done.. And ( boy do i feel stupid ) I checked the carb and the idle screw was so far out it was flooding the cylinder. Mr stupid here had forgotton to screw the idle screw in to the correct setting and the motor was just running on the top cylinder becasue i had adjusted tha carb idle screw.
So we finally got out on the water today and boat flew.. straight up to 26 mph not even at WOT. My wife was overjoyed she had the boat flying along.. and though t had enough power left to easily brake 30mph.
The only thing we had was a rough idle and cut out but that was becasue i need to ajust the low end throttle... but thats an easy fix...
Thanks for all your help!! And happy easter to you all

 

[DJ]

Re: Johnson 50 hp suspect water entering bottom cylinder.

bagnallt,

Thanks for checking back in. Those that helped you really appreciate the feedback.