terry wrote: > Update time. Away from the boat last weekend, so no progress until > yesterday. My brother came over for the afternoon and between us we > managed to get the cylinder head lifted clear of the block. The nature > of the engine problem then became self-evident. One of the pistons had > burnt through and cracked. Presumably a piece of carbon dislodged from > somewhere and stuck to the piston crown causing a hot spot and the > piston to burn through. The FR engines have an access plate which > allows you into the crankcase, and it is possible (just) to undo the big > end nuts through this opening. The nearer one is relatively simple, but > the far one is an absolute sod. I spent the best part of today swearing > at it and scraping my wrists and knuckles on the crankshaft, but > eventually managed to get the nut undone and the piston out of the bore. > The crack in the piston runs from the crown right down the skirt, and > has caused the piston rings to break. Fortunately, the cylinder bore > looks undamaged. I've had a close inspection by torchlight and can see > no signs of any scratches. With any luck, it will just be a case of > replacing the broken piston and rings with a new set and bolting it all > back together again.
Great news that you now know the problem and that it confirms (although a lot worse than) my suspicions. Where would you like me to send the invoice for diagnosis? I should warn you that remote diagnosis over the web is more difficult and, therefore, attracts a higher invoice charge; trust that'll be OK? ;-))) Roger
