Scattered piston- engine ruined??

[IGKNIGHTED]

I've had a very bad day- I took my 1992 Checkmate out for only the second time since I bought it and blew the engine. I was cruising along and the motor started rattling but I had to go about a 1/2 mile to get back to the dock with my wife and 2 year old. It stalled just as I got to the dock.

When I got home I pulled the spark plugs and to my horror I found the top right cylinder on my Black Max 135 had a major explosion of the piston- I could see chunks through the spark plug hole. I took the head off and sure enough the piston had a hole in the top and stuck to the cylinder. The rod had broke and left the the piston stuck.

I moved the flywheel starter ring and the rest of the cylinders move freely but when I turn the prop I hear a scraping sound.

Is this engine toally ruined or can it be salvaged? If so how much am I looking at? I already paid a ton for the boat- $6500 but it is super clean and in showroom condtion. (its a 1992 Checkmate Pulse 170)

Thanks in advance for the replies.

 

[WillyBWright]

Re: Scattered piston- engine ruined??

I expect it to be salvagable. It'll need an overhaul. Holes burn from bad gas, advanced timing, lean condition. You'll want to address the cause.

 

[redjmp]

Re: Scattered piston- engine ruined??

You will want to check the other bank as well and see if the top piston is starting to fail as well. It looks to me like you might have had an over heat from a failing impellor or from head gasket blowby.
You are looking at a complete tear down. You will want to inspect the block and crank for damage. If the con rod is still attached to the crank, then I doubt the the block is undamaged. You may have gotten off lucky and only need to relace the piston, rings and rod along with a rebore of that cylinder.
If you spin your own wrenches then it could be under a $400 job.
If it is too far gone your best bet is to try and find a power head and to list all the salvagable parts on ebay to recoup some or all of your money.
You will also want to check for the cause of that scraping sound when turn the prop as that is most likely piston parts grinding in the lower unit.