High Pitch Noise?

[impulsiveRX=7]

There is a high pitched, squealing noise coming from the rear of my engine. I’ve checked the midshaft, tightened all the hose clamps. Any ideas before I start disassembling everything?

Engine is a 61x/62t all stock in a squarenose. Turns over by hand just fine. Starts right up without choke or primer. Runs ok. Rode it all day Saturday.

 

[kevbo]

I have heard that from stock SN waterboxes when the engine was revved out of the water. It was only at high rpms though. Apparently the sheet metal baffling is resonating.

 

[impulsiveRX=7]

Do anyone think if this is an air leak or a failed bearing that it would still be running? Seems like I would have other symptoms if it was that serious, right??

 

[Myself]

High pitched squealing sounds like a bad bearing to me. BUT......I have heard a strange noise like that once on a bad head o'ring.

 

[impulsiveRX=7]

Stock head

 

[impulsiveRX=7]

I can’t figure out how to put a video here, so here is a link to it.

https://www.facebook.com/video.php?v=870688891318349

 

[Myself]

Sounds like it happens at about 1/4 throttle opening, then goes away, then returns as the engine slows back down to that 1/4 range. I'm leaning more towards maybe an intake gasket or throttle shaft sucking some air and screaming. I think you're going to need a mechanics stethoscope with a length of tubing on the end. Give it some 1/4 throttle opening and closing while searching around with the tubing for where it's the loudest. It could be something like a mid-shaft bearing but it really doesn't have that whirring type noise I usually hear with a bad bearing.

 

[SXIPro]

All I know is that it totally freaked my dog out when I played your video. I can barely hear the squeal because I'm old, but my fuzzy buddy Hobbes, was not a fan at all.

 

[impulsiveRX=7]

https://www.facebook.com/video.php?v=840144201121433

 

[mthomps]

All I know is that it totally freaked my dog out when I played your video. I can barely hear the squeal because I'm old, but my fuzzy buddy Hobbes, was not a fan at all.

I watched the video and my dog did the same thing, then shortly after i read your post

 

[badvinny]

Crank seals are leaking, bearings will be next.

 

[impulsiveRX=7]

I pulled the engine out. Found a loose pulse fitting. Crank seal is not leaking. Send it?

 

[subnsxr]

Tighten the pulse fitting and post another video

 

[impulsiveRX=7]

Well, finally got around to putting the engine back in. Initial test run, the sound is gone. Crossing my fingers that the loose pulse fitting was it. If you look back at my videos, that pulse fitting is right in the center of the video where I was looking for the noise.

Will report back if something else blows up.