How good are your diagnosis skills?

[Kevlarr]

Ok, time to spill. It was actually running rich. Funny thing is just about every guess is something I checked BEFORE I found the problem, including the mag coming loose.

I pulled the plug and noticed it was black and sooty but not at all wet (guess that comes from running 100:1) so off came the carb. My first thought was the float had gone bad but when I pulled the bowl there it was happily floating on top of the gas. When I flipped the carb over is when I got my surprise. The arm that holds the needle was bent to the point that no matter how full the bowl got the needle wouldn't close and it was bent where the needle clips in not the fingers that contact the float. How that happened WHILE I was riding is beyond me!

 

[scotto-]

Boo, hiss...I was hoping it was interplanetary aliens messing with you

 

[GearNut]

So it was flooding. Hmmmm.....
Got me on that one!

 

[scotto-]

So it was flooding. Hmmmm.....
Got me on that one!

Hey GNut, he got everyone on that one.....it was the opposite of running out of gas, that's all

Just wonder what would make it knock or ping if it's gettin' too much gas??? I would think it would be coughing or spittin' with that condition. 4-strokin' so too speak....

 

[Dan]

Preview the crowd applause Sound Effect

So it was MBG. (Motor Bike Gnomes) Or aliens.

Do another one, do another one.

 

[GearNut]

Hey GNut, he got everyone on that one.....it was the opposite of running out of gas, that's all

Just wonder what would make it knock or ping if it's gettin' too much gas??? I would think it would be coughing or spittin' with that condition. 4-strokin' so too speak....

Yeah, the knocking or pinging is what led me to thinking that it was too lean. Too lean = too hot and any carbon buildup in the combustion chamber would start glowing and act like a glow plug, causing pre-ignition or pinging. An exhaust leak can draw in air and lead to an afterburner effect in the exhaust system and cause popping, but that is really more of a 4-stroke problem than a 2-stroke problem. However, an exhaust leak can cause a 2-stroke to lean out as well.

 

[scotto-]

Yeah, the knocking or pinging is what led me to thinking that it was too lean. Too lean = too hot and any carbon buildup in the combustion chamber would start glowing and act like a glow plug, causing pre-ignition or pinging. An exhaust leak can draw in air and lead to an afterburner effect in the exhaust system and cause popping, but that is really more of a 4-stroke problem than a 2-stroke problem. However, an exhaust leak can cause a 2-stroke to lean out as well.

Yes, it overheats as well. Not good. Any lean condition in a 2-stroke is cause for a seizure...

 

[Kevlarr]

See post #11, that was the second clue.

 

[GearNut]

No maple leaves and no bees. lol

No loose ignition wire Dan.

I was kind of disappointed that the camera didn't pick up the pinging sound more. It was a sound that made me think I had a rod coming loose and it made me closely examine the head gasket. But I think it was detonation in the expansion chamber.

There's your second clue.

Maple leaves and/ or bees in the air cleaner would have caused a fuel rich or protein rich condition.
Loose ignition wire would have caused a misfire condition. Detonation in the chamber should have been the clue, but I have never experienced that in a 2 stroke before.

 

[scotto-]

Maybe you were running out of gas...only the other moderators will appreciate that
Tom

Tom, did you miss this post?

It really sounds like you ran out of gas....filler up? You get that detonation sound as your engine leans out while it's starving for gas. On a 2-stroke it's a seizure theoretically when you run out of gas

I'm no moderator, but I got a kick out of it!

 

[2door]

Scott,
I was being facetious and referring to a converstion that took place between the other mods and myself. I'm waiting for one of them to spill the beans here but maybe they're all either afraid of what I'll do to them or they have a lot of integrity
Tom

 

[Dave31]

Scott,
I was being facetious and referring to a converstion that took place between the other mods and myself. I'm waiting for one of them to spill the beans here but maybe they're all either afraid of what I'll do to them or they have a lot of integrity
Tom

Anyone who copies and pastes this into the public forum will face the wrath of one embarrassed guy.
Tom

I'm afraid

 

[scotto-]

Scott,
I was being facetious and referring to a converstion that took place between the other mods and myself. I'm waiting for one of them to spill the beans here but maybe they're all either afraid of what I'll do to them or they have a lot of integrity
Tom

Tom, no prob, I understand....was just sayin'. I still think it's funny, the "out of gas" thing....
Cheers,
Scott