noise in flywheel, loose bearing?

[macauto]

Recently after pull starting my motor, I noticed that the flywheel made a clicking noise when pushed back and forth. This sounds like a loose bearing on top of the power head, this is on a Yamaha 115, 84'. How hard is this to fix? No movement can be scene when wiggling the flywheel, but a click is heard.<br />Thanks<br />Brian

 

[ob]

Re: noise in flywheel, loose bearing?

When you say your moving flywheel back and forth I assume you don't mean in a rotating motion.If not and you can push it in a side to side motion and detect clicking then you have a problem with crankshaft main bearing.Are you having any specific trouble with motor?

 

[G DANE]

Re: noise in flywheel, loose bearing?

Are you sure the flywheel and cranck actually moves ? A worn stator plate boss and guide can make the statorplate click when magnets pass coils, causing the plate to move up and down. common on older motors, and the shims are replaceable on most.

 

[macauto]

Re: noise in flywheel, loose bearing?

Ob, when I put my hand on the flywheel and move it parallel to the water, pushing back and pulling toward me, that's when I hear the clicking. I think I can hear the clicking a little when the engine in running with the cowling off. (Not at all when it's on though). Currently there are no engine problems, runs great. How hard is this to fix? (Lets assume it's just the top bearing, can it be tightened like a wheel bearing, or replaced -- any idea of cost)? Thanks<br />Brian

 

[ob]

Re: noise in flywheel, loose bearing?

No,unit will have to be disassembled to change.Don't know if you have access to dial indicators,but setting one up on flywheel perimeter will give you a definate on radial movement of top main bearing.Also,could be problem with fly wheel on crankshaft where it is keyed .Check to insure flywheel nut is torqued properly.

 

[macauto]

Re: noise in flywheel, loose bearing?

Thanks Ob, I don't have that equipment, but maybe i'll get someone to take a look at it. Most likely it is the bearing and not the flywheel nut, it is a 84', never been rebuilt. Would it even be worth fixing?(cost compaired to new motor?)<br /><br />Thanks<br />Brian

 

[ob]

Re: noise in flywheel, loose bearing?

If all seems to be running ok now yeh,I think its worth it.Get a couple of diferent quotes from reputable facilities if you don't feel like tackling it yourself.If you decide to do it yourself ,with some general mechanical abilities and a manual specific to your motor its not that big a deal. Good luck

 

[macauto]

Re: noise in flywheel, loose bearing?

Ob, I do have the shop manual, and was looking at it. But it seemed as though i would have to pull the entire crank off, and press out the bearing, which involves pulling pistions, or do the bearings slide right off the crank when you take the head off? Thanks for all the help.<br />Brian

 

[G DANE]

Re: noise in flywheel, loose bearing?

Hi again Macauto<br /><br />If the upper main bearing is worn, cranck will move in play when it runs. Usually a movement will cause seal to leak, and fuel til squirt out in top. Please be aware all bearings have a small amount of play. I´d let someone look at it if in doubt, especially if it causes no leak. I´m not familiar to Yamaha, only OMC, but Yamahas are made a lot based om the experience OMC got through history, and I assume its the same. If it is, cranck can be lifted amd upper bearing changed when intake side cranckcase half is off, without removing pistons, nor disassembling rods.<br /><br />If this is the only issus you got, its surely worth fixing.

 

[macauto]

Re: noise in flywheel, loose bearing?

I don't see any leaks yet, and I gave it a close look. This play in the bearing might be normal, you can hear just a little click, and see no movement, and don't think it's a loose flywheel. But no problems as of yet, maybe I’ll look into fixing it before it gets too much worse. Thanks for all the help<br />Brian