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tohatsu m40d head problem

a few months ago i had an over heat. motor runs has new waterpump, new head gasket, head is not cracked, still getting water in lower cylender. any ideas???
 
If the head is OK, and the cylinder walls are OK (did you Zyglow check them?), you are likely getting some water into the crankcase, which is then being drawn in with the air/fuel mix.
 
ok I did not zyglow test them, mostly because I dont know what this is or how to do it. How might there be water getting in to the crank case? Also i did not change to water pick up tube rubber grommet when i changed the water pump, shoul i do that? I do know for a fack that there is not water in my fuel tank if that helps. getting no water in the carbs
 
Zyglow is how one finds microscopic cracks in nonferrous metals. You could have a cracked block or head. The wp grommet would not cause water to get into the cylinder. Nor would a little water in the fuel. What is your compression? What is the head bolt torque?
 
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ok i will plan on testing compression tomorrow, how exactly do you zyglow test this thing? where can i get it? i cant find any thing on how to do this on the internet
 
Zyglow is the aluminum equivalent of magnaflux (which would be used on iron or steel). Typically not done at home, but rather by a competent engine rebuilding or machine shop.
 
And you still get sea water in the lower cylinder? If you aren't getting it from the head gasket, you must be ingesting it, possibly through a problem in the crankcase. Maybe Elvin has diagnosed something similar... He's the 40D expert...
 
a few months ago i had an over heat. motor runs has new waterpump, new head gasket, head is not cracked, still getting water in lower cylender. any ideas???

No short cuts on something like this. If you have elimated the fuel system and ignition system...You need to tear the block apart and do a visual inspection.
 
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