Last winter, I drained the antifreeze
from my engine
and removed the heat exchanger
in order to give it a good clean.
I replaced it, filled up the anti-freeze EXPANSION TANK
and went sailing for the FIRST time this season (there's been lots of problems this year !). On my way out of the harbour, just, luckily, as I had reached open water
, the engine
started to RAPIDLY overheat. I quickly turned it off.
I sailed around until the engine had cooled down, and then made it back to 100' of my slip before I had to turn the engine off again. I docked OK (single-handed !)
At the slip I started to think what could be the problem. I'd replaced the muffler
this spring, but water
was coming through the exhaust
pipe and the ammeter was showing a charge, i.e. the raw water
side was OK, and the V belt was OK. So it must be the Coolant
To cut a long story short, there was not enough antifreeze
flowing around the engine because the anti-freeze had not flowed from the EXPANSION TANK to the HEADER TANK due to the filler cap not opening the valve. (It wasn't immersed in fluid, so how could it !). I learnt from an old time mechanic
, that you should always make sure the HEADER Tank is full by removing the filler cap and directly filling it as necessary. Leave the cap off for a short while and run the engine, and top up as necessary. Then replace filer cap and fill up EXPANSION TANK. I had to undo my feed tube from the EXPANSION to the HEADER as it had an airlock in it.
Engine now runs OK !!
Hope this helps other people in the future !