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90hp v4 starboard cylinder overheat

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fishhawk90

Member
thought i showed u guys what I've discovered in the block. It appears that the cylinders worn out over the years & cylinder 1 was the first to start loosing compression not burning right causing the mixture to leak pass the rings & overheat that entire side of the block. I am left to troubleshoot as to why the heat sensor did not trigger slow mode. I have measure the ring end gap & got .039 give or take a few thou. With that said i plan on going with the .02 o/s pistons hone the cylinders & see how it runs.

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If the piston ring did not break then that cylinder ran lean. Look at the carb for that problem or a seal issue. A lean condition will not trip the temp sensor if the water pump is still pumping water. If the water pump would have failed you would see more damage to more pistons. Your theory for losing compression and not burning right is not correct. Unburned fuel has a cooling effect not an overheat effect. Not enough fuel on the other hand will cause the damage your piston has.
 
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I put a torch to the heat sensor & didn't get a close circuit, so that explains why their was no warning. also both tstat's were stuck open.
 
fishhawk90 said:
I put a torch to the heat sensor & didn't get a close circuit, so that explains why their was no warning. also both tstat's were stuck open.
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Get a factory manual and read it cover to cover before you do anything else. That way you can learn how the systems on your motor work.
 
you are right, i did recall the sensor wire running straight to the buzzer under the dash. As for the bore the machinist said .020 can be done by hone.
 
You need a different machinist !!!!!! That is a Sunnen rigid honing machine and yes you can bore a block with it but not a outboard block. Why???? Look in the bottom of your cylinders and then you will know. You cannot hone out a block .020 with a hone, if you could you would use 100's of dollars worth of stones. And a spring hone will never work. Do what ya want as looks like you want to buck the answers...
 
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