Nauti Fox
Well-Known Member
It started a little while ago when the port engine developed a strange habit of overheating on a restart. It was fine after bleeding the cooling system at the highest point on the engine, so was air locking for a strange reason, it does have a self bleeder which runs up to the expansion tank. Once running and bled it would run faultlessly, with no sign of it pressurising the expansion tank.
I had some spare time so started to investigate. The first thing I noticed was the self bleeder wasn't, the return to the expansion tank would work (shining a torch down the filler) after bleeding the cooling system, but not on the restart ( even after only a few minutes).
The filler
And where it is underneath, the bleed line fitting is at the top left of the tank
And as always, its so accessible......
So I traced the line from the top of the engine to the tank....and to say it took a tortuous route is an understatement. It ran from the engine, then down the side of the hull to the bilge, through a bulkhead and then back up a bulkhead, through the floor and up to the tank.
I removed the hose (oh it sounds so easy saying it!) and ran it straight from the engine and out of the window into a bucket.....and lo...it worked every time.
The fitting on top of the engine
And running the hose up to the window
And into the bucket
I've now re routed it after drilling various holes and all seems ok.
Not sure why it started doing this after all this time and I'll obviously keep an eye on things....but its not the first time these ancient engines have decided to do something different for no apparent reason......
I had some spare time so started to investigate. The first thing I noticed was the self bleeder wasn't, the return to the expansion tank would work (shining a torch down the filler) after bleeding the cooling system, but not on the restart ( even after only a few minutes).
The filler
And where it is underneath, the bleed line fitting is at the top left of the tank
And as always, its so accessible......
So I traced the line from the top of the engine to the tank....and to say it took a tortuous route is an understatement. It ran from the engine, then down the side of the hull to the bilge, through a bulkhead and then back up a bulkhead, through the floor and up to the tank.
I removed the hose (oh it sounds so easy saying it!) and ran it straight from the engine and out of the window into a bucket.....and lo...it worked every time.
The fitting on top of the engine
And running the hose up to the window
And into the bucket
I've now re routed it after drilling various holes and all seems ok.
Not sure why it started doing this after all this time and I'll obviously keep an eye on things....but its not the first time these ancient engines have decided to do something different for no apparent reason......
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