Cracked Cylinder Head

[CBaymoz]

Hello to all members.
Not sure where to Start. My twin DF90A Lean Burn, not 200 hrs yet. Dumped my boat on sea here @ CashewBay Mozambique Inhassoro. Turned the key, one motor fired, shook it's head and died, the second motor didn't start. Back on the trailer to find the conrod has cracked the cylinder block on both motors. I'm devastated. Can't believe this has happened!!!
Not sure how and why. Been told I have got water in through the air filter, or maybe through the fuel. Running filters and water separators. Yes my staff removed the covers and rinsed the engines off with "salt-off" as has been done many times before. Please give me some advise on why this happened.

[Moonlighter]

If you've got water into the cylinders and hydrolocked the engines, then that is what will happen. Big damage.

Either very bad luck for it to happen to both engines at the same time, or, very bad procedure used by someone to send water into the intakes of both of them - from what you said, possible that whoever removed the covers and "rinsed" them off may have not known what they were doing. Or, you took a wave over the stern of the boat.

To be honest, I wouldn't think there is any need to routinely "rinse" the motor off with water with the cowl removed at all. If you are concerned about salt water under the cowl, you are far better off spraying the engine under the cowl with a lanolin based spray - that will protect it very effectively from the salt and water damage. That's what Ive done.

If you took a wave over the stern, then likely you may be able to claim the damage on your insurance. Check your policy and talk to your insurer.

[CBaymoz]

Just bad procedures, disappointed that the air filter do not have a water drain in case of water getting into the air filter cover. Thanks for taking the time to respond. Costly lesson, never to be repeated.

[donsmarine]

did you launch with engines down and got water in thru prop exhaust?

[redlowrey]

Hello to all members.
Not sure where to Start. My twin DF90A Lean Burn, not 200 hrs yet. Dumped my boat on sea here @ CashewBay Mozambique Inhassoro. Turned the key, one motor fired, shook it's head and died, the second motor didn't start. Back on the trailer to find the conrod has cracked the cylinder block on both motors. I'm devastated. Can't believe this has happened!!!
Not sure how and why. Been told I have got water in through the air filter, or maybe through the fuel. Running filters and water separators. Yes my staff removed the covers and rinsed the engines off with "salt-off" as has been done many times before. Please give me some advise on why this happened.

''''''If you launched off the beach and miss timed a wave and went stern first back into the sea, the force of the water would travel up the leg and into the engine via the exhaust valves. If you could not start your engines after the wave dumped you, that is where the damage would have been done. Back on land with the hosing off the engines I doubt it, the starter would not have the torque to keep rotating the crank once it hydro locked.

[catacom225]

Hydrolic lock

After distroying one engine I carn't imagine what would make you attempt to start the other engine