All started last weekend, when after returning to the slipway with the boat I heard the engine “pop” a couple of times!
After what was a gentle cruise of a day, mostly around the 20/25knot mark my first thought was I’ve got a dodgy plug.
Temp fine, oil pressure good. Ah well I’l check the plugs when I get it home.
Skip forward to Tuesday evening and I get home from work at a reasonable hour so let’s do them plugs.
Oh dear that’s not good! Rusty plug, never a good sign…
Better do a compression test then. All’s fine until I get to #3 and #5
Bugger!
Only one thing for it. So an hour later here’s where I’m at.
As you can clearly see water has been getting into the middle and back cylinders!
Turning my attention to the head I do a leak down test on the valves and cylinder head with penetrating oil to check for cracks or bent/burnt valves. Also checked the rings.
Good news is there appears to be no damage other than some water scorching on the inlet valves.
And 2 push rods are slightly bent, less than a couple of millimetres.
And the culprit for all this? Exhaust gasket between manifold and riser leaking and filling the bore when stationary. Then blowing the gasket when running due to excess pressure in the cylinder
Ok so time to clean up and rebuild.
I’m going to need gaskets, a couple of inlet valves and a couple of push rods.
So Friday afternoon and were back together.
Now who’s gona clean my bilge for me!
Well that was a long week.
