Cracked flywheel

[greg baranitsky]

I have a 1970 80hp Merc that started to make a lot of noise so I removed the cover and took hold of the flywheel. To my surprise it felt loose! So I removed the eight bolts on the hub and it was cracked all the way around. What would cause this? Are replacement flywheels hard to find? Any info would much be appreciated.<br /><br />Thanks<br />Greg

 

[chuckster819]

Re: Cracked flywheel

Hi Greg. <br /><br />Sorry about your problem. <br /><br />If your serial number is between 2559001 and 3493912 it appears you’re looking for part #225-2494A37 which has superseded #225-2494A10/14. mercruiserparts.com showed that part as currently unavailable. If you do a Google search for "mercury outboard parts" you may get some help as far as a replacement. You may be looking at salvaging another motor, however.<br /><br />Search ebay.<br /><br />It might be a good idea to find out if this flywheel is interchangable with other hp's, etc. <br /><br />Someone else may have some suggestions. I have no clue if it can be welded. It seems like you would also want to figure out why or how it cracked in the first place.<br /><br />Chuck

 

[Chinewalker]

Re: Cracked flywheel

Hi WaterAffair,<br /> What broke on your flywheel is called a "flex plate" and they do break from time to time. Anything that causes extra vibration in the motor can contribute to it - a bent propeller, wobbling propshaft, etc. Sometimes, they just start a hairline crack and go from there - for no obvious reason. Not hard to replace, but make sure you use lock-tite or similar thread locker when re-installing so that nothing unbolts itself down the road...<br />- Scott

 

[greg baranitsky]

Re: Cracked flywheel

Ok my sn is 2886565 so I guess your right on the flywheel Chuck. <br /> <br />Scott:<br />Can I replace just the flex plate or do I need the complete assy?<br /><br />Thanks for your help guy's<br />Greg

 

[DJ]

Re: Cracked flywheel

Try here.<br /><br />www.twincityoutboard.com

 

[Chinewalker]

Re: Cracked flywheel

hi Greg,<br /> It is possible to simply replace the plate. I don't think the outer ring of the flywheel has any bearing on motor timing as all it does is house the magnets for the charging system, but it may have a bearing on flywheel balance. If possible, reassemble with the outer ring at the same positional relation to the inner hub. Like I mentioned previously - use LockTite threadlocker on the bolts to keep them from backing out. <br /> You may find it cheaper to simply buy a good, used flywheel from an outboard salvage place like DJ mentioned, among others. Check locally, too.<br /> Good luck!<br />- Scott

 

[greg baranitsky]

Re: Cracked flywheel

Thanks again..The search begins. <br /><br />Greg

 

[greg baranitsky]

Re: Cracked flywheel

Yahoo! I found one at a local marine shop! Old fella named Len had a couple of them..50 bucks for the flex plate. Any how he changed it over to my flywheel for me (no charge) and when I got home I realized that I had forgot to ask him what the torque should be for the flexplate to the hub? Would any of you know what it would be?<br /><br />Thanks agian<br />Greg

 

[chuckster819]

Re: Cracked flywheel

Hey Greg...<br /><br />It's always a treat to see "Yahoo!"<br /><br />I checked my Clymer's and didn't find a torque spec for the plate bolts. It looks like the main flywheel nut is 85lbs.<br /><br />I would take the advice already given above and snug them down good with lock-tite.<br /><br />See ya on the water!<br /><br />Chuck

 

[greg baranitsky]

Re: Cracked flywheel

Sounds good! I have some blue lock-tite so I'll use that and give them a good snug. I'll also put some safety paint on the heads of the bolts to verify that they are not coming loose.<br />Thanks agian for all of your help.<br />Greg