Crank Shaft Cracked At Fly Wheel

[joseph L]

1999 150 Merecry the motor was vibrating and starter was not engaging and somone told me to check fly wheel and it was loose. the crank shaf was cracked right at the fly wheel. what would cause that ANY INPUT

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

any input help

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

any input

 

[CraigC]

Re: Crank Shaft Cracked At Fly Wheel

Ouch, the crankshaft is broken at the flywheel, that's a tough one to take.
Was this an otherwise good running engine prior to this? Or did it have a serious problem once before? If it wasn't damaged before (i.e. blown up and put back together with a bad crank!), then I would think it was most likely just a weak/bad crank to begin with. They're normally pretty tough in my experience, but every once in a while you could just get a weak part. As for other causes, there's not many I can think of but maybe someone else will weigh in here....running it with the flywheel loose would normally damage the flywheel NOT the crank, but anything's possible I guess...was the nut loose on flywheel by any chance? How's the upper bearing in that motor - any play in crank at top with flywheel removed? A long shot I think that would be the cause, but trying to cover everything for you.

 

[CharlieB]

Re: Crank Shaft Cracked At Fly Wheel

Any chance that this boat has had repeated 'air time', wave jumps that lifted the prop loose froom the water, instant over-reving then rapid full loading back into the water?

It's really a moot point now, you need a crank and a gasket set.

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

Motor was in perfect shape, never had any problem or brake downs. I took very good care of it. It seemed odd to me that the crank cracked right at the fly wheel. It made me start thinking so I called Mercury and told them the situation and asked if they had any of these same problems. They asked me for the serial number of the motor and called me back the next day to tell me to bring it to the nearest Mercury dealer and they said they had problems with the fly wheels that year and the fly wheel nuts stood tight but the fly wheel somehow gets loose and cracks the crank shaft. They said they were going to give me a new powerhead with no charge, I was shocked. They really stand behind their product. I saved myself alot of money with one phone call.

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

Hi have a god day today

 

[Joe Dirt]

Re: Crank Shaft Cracked At Fly Wheel

Wow Joseph- that's a pretty impressive feather in Merc's cap. Good to see a manufacturer stand behind a product like that willingly. They could have said anything, but they took care of it.

Kudos Mercury... And I'm an OMC tried and true guy!

 

[CharlieB]

Re: Crank Shaft Cracked At Fly Wheel

I suspect that there part manufacturer made an error in machining the angle of the taper in the flywheel, making a 'loose' fit to the crank, NO nut will hold it steady.

Merc KNOWS whats wrong and that it is much cheaper to take care of you than get drug thru the courts, again.

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

I should have the boat back by the end of the week

 

[jimmbo]

Re: Crank Shaft Cracked At Fly Wheel

I hope you bought a few lottery tickets that day too!!!

 

[joseph L]

Re: Crank Shaft Cracked At Fly Wheel

Wasn't that lucky at the Lottery.

 

[Willyclay]

Re: Crank Shaft Cracked At Fly Wheel

Very impressive response by Mercury! Hope it all goes well. Good luck.

 

[DRIFTER_016]

Re: Crank Shaft Cracked At Fly Wheel

Now that you have a new power head, don't forget to break it in properly.
It would suck to screw it up.