Help! crankshaft play

[duppyconqueror]

I had another thread going but figured it might be good to start a new one now that I have identified the problem.

one question is this amount of play in the crank normal??

[YOUTUBE]100_0212.MP4 - YouTube[/YOUTUBE]

replace bushing/bearing?

 

[Newoldstock]

Yup looks Normal.

You want loose, loose is fast.....

Make sue when the cover is back on you can still feel a little in and out on that crank.
Just enough so you can say you feel it is all you need

 

[duppyconqueror]

I shoulda mentioned I'm getting a loud rattle noise thats why I opened it up. So that amount of movement would not be the cause?

 

[Bluethunder3320]

when you have the side cover off there is no support on the crank, so it will have slop like that. normal. with the cover back on it should go in and out just a little bit.. too. NOT up and down.

a rattle is probably a piece of sheet metal or something else on the bike/kart. usually when its an internal problem its a knock.

 

[duppyconqueror]

well It definitely seems to come from the motor, but I'll start it with it off the bike just to be sure. The governor gear is kinda loose maybe that's causing the rattle? Idk but its driving me crazy trying to figure out where this noise is coming from

 

[duppyconqueror]

Finally found the problem fellas! It took a long time but It should have been obvious :doah:

The camshaft does have up and down movement. Behind the flywheel there is a cover that separates the flywheel from the block. i saw that the flywheel has ripped into the sheet metal cover (the cover goes around the front of the block and the little silver box that houses the oil sensor wires attaches to it). Well the flywheel has torn into that cover and every time the magnet end of the flywheel comes around it swipes that metal cover. The magnet had metal shavings clinging to it. I'm guessing this could be fixed by replacing the bearing. I'm hoping it will be that simple. Thanks for the help guys and as always input is greatly appreciated.:thumbsup:

 

[Newoldstock]

Finally found the problem fellas! It took a long time but It should have been obvious :doah:

The camshaft does have up and down movement. Behind the flywheel there is a cover that separates the flywheel from the block. i saw that the flywheel has ripped into the sheet metal cover (the cover goes around the front of the block and the little silver box that houses the oil sensor wires attaches to it). Well the flywheel has torn into that cover and every time the magnet end of the flywheel comes around it swipes that metal cover. The magnet had metal shavings clinging to it. I'm guessing this could be fixed by replacing the bearing. I'm hoping it will be that simple. Thanks for the help guys and as always input is greatly appreciated.:thumbsup:

WHa?

Take pictures of everything you just sugested as being a problem please

 

[buckeye]

Yeah, that doesn't sound like you need to replace a bearing.

 

[duppyconqueror]

Ok I got some footage for you guys. Its hard to see with the flywheel on but I cant find my 7/8 socket so I haven't been able to get it off yet.

Here's a link to a video series that deals with the same problem on an old Briggs:

Hallaran's Channel - YouTube

The problem is that the bearing that goes around the crank is worn and allows up/down movement of the crank. This causes the flywheel to wobble and collide with the metal which caused the noise.
here's a pic of the area we are talking about:

here's a close-up of the scoring and cutting of the metal (hard to see in the pic but trust me its been ripped through)

needless to say when that flywheel hits that piece of metal it becomes very hard to turn the motor over as its causing friction on the flywheel. Here's a video showing the up/down movement of the crank:
[YOUTUBE]6.5hp clone problem - YouTube[/YOUTUBE]

So I'm pretty sure that is the source of the sound I was getting and I just hope that it is as simple as replacing that bearing that goes on the crank.

 

[125ccCrazy]

have you thought about bending the metal out of the way a little? unless you can wiggle the crank up and down with the engine assembled I dought the bearing is bad, if was that bad the oil seal would be leaking like a sieve behind the flywheel.... also make sure the flywheel is tight and not oscolating...

 

[buckeye]

Second that. That engine is to clean to have a bad bearing. You a engineering student? JK. I think you might be making this garder than it is.

 

[duppyconqueror]

Yea I will check for oil leakage when I take the wheel off, but there is no way to bend the metal as It is already up against the block. The flywheel is definitely not right. Idk if it is the bearing but Idk what else could make the flywheel go crooked like that.

 

[buckeye]

Loose flywheel nut. Or did you already say ya checked. If nothing else you are learning the workins. Fun huh?

 

[duppyconqueror]

well buckeye you know your stuff. and I was making things harder than they needed to be. no messed up bearing just a bent metal cover. A stick probably pushed it bending it into the flywheel. flimsy ass cover. All i gotta do is bend or cut that cover out of the way and put everything back together and I learned a lot in the process which will make diagnosing future problems a lot easier. Thanks to everyone for the support and help especially mr buckeye. I'm thinkin its about time to start my next mini after this :thumbsup:

 

[buckeye]

Cool man. Glad it isn't gonna cost ya anything.
You are welcome. I make things way to hard often.