diagnosing blown power head

[habbi]

I have a 250 Johnson who's lower starboard piston is not moving, I asume it is a broken connecting rod. When this happened it still ran for a few seconds and filled with water and then stalled. If I tilted it up and let the block drain out the carb throats and then tilt it back down it would again start and run for a few seconds until it filled with water and stalled. Is the block punctured from inside or is there a chance the cylinder wall is punctured and in either case is it repairable or does it mean replacing the block or cylinder. Thanks

[Wgoodrich]

If the piston does not move then all depends where that rod went after it broke loose. If you restarted again chances are you are talking at the least a new crank, cylinder set, piston, rings and rod. Be aware that these are sensitive engines. If you take this on yourself be sure to follow rebuild instructions in your manual to the letter including locktight and torque proceedures. Otherwise you will be doing it again soon.

Good Luck

Wg

[Roger]

I can only second wg in that this isnt a job for the diy unless you are experienced with outboard motor rebuild. Unless you want to replace the entire powerhead as an assembly. If you take this to a marine repair shop my gut feeling is that they will suggest a powerhead assembly either rebuilt or oem. Oem will be about a thousand more than rebuilt plus labor. You will get a one year warranty either way. Do it yourself and its on you. I suspect your block or cylinder wall has a hole/crack in it and is not repairable. If you do this yourself make darn sure, if the block is repairable, that you use a marine machine shop. You will have to front a core charge from the original block until you make payment on the rebuild work. It most likely will not be the one you send in unless you use a local shop. Also check your reed blocks these sit inbetween the cylinder block cover and intake manifold. When these fail they can get sucked inside the cylinder and score the walls or sieze the piston.
Have you done a compression check on all the cylinders?

As wg mentioned if you attempt this yourself absolutely obtain the correct torque spec's from a repair manual, I would like to have a buck for every owner rebuild that fails again the first or second time out.
Remember to that outboards are special tool crazy,,,,so fair warning.

Roger