Overheating Engine

Mopedamauter79

New Member
Mar 31, 2008
254
0
0
Ottawa
Just wondering what could be the reason for the engine to overheat and how to cool it off. I have CH80 Engine if that means anything. I know it was overheating as I can only idle and rev the engine when it's really hot. That and I could feel the heat through my pants. It acts up when it's to hot. It would putter like it does when say your going to slow and it's about to stall due to a very slow speed. Another way to describe it is the sound it makes when you forget the to switch the gas valve to the one position and it's starving for gas..

I hope I made this clear enough.
 

Ritchie

New Member
May 20, 2008
14
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0
Manitoba, Canada
Air leaks cause lean conditions which kills the 2 strokes. Same goes for incorrect carb settings. If in doubt, run rich.

There are guides on this site (or links) to read your fuel/air mix from your spark plug colour.
 

Dave31

Moderator
Staff member
Mar 1, 2008
11,204
29
38
Aztlán, Arizona
Yes, you are running lean to cause overheating, vacuum leak at manifold or at carb. Or the carb need's to be looked at.

I suspect your plug is white? Here is a chart of plug's

 

Mopedamauter79

New Member
Mar 31, 2008
254
0
0
Ottawa
Carb does not appear to have any leaks and I retightened it to make sure. The spark plug I have no means to take off. I can't find the tool that came with the engine kit. Where can I get one in Ontario ?
 

Ritchie

New Member
May 20, 2008
14
0
0
Manitoba, Canada
Any auto store, canadian tire etc. home depot/ rona (in the lawn mower section). There are generally 3 sizes, you want the 3/4 inch one (if yours is a Z4C plug), I'd say look at the lawn mower sections first.

Just make sure you can exchange it if you need a different size.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
236
63
up north now
The best thing to do is remove the intake manifold from the cylinder and coat both sides of the gasket with RTV sealer....make sure you take the gasket off and coat both sides of it then re-install it.

Make sure the carb is fully on the manifold and tight. Check your head fasteners as well. (four nuts on the top of the engine surrounding the plug). Just snug them down, don't over do it.
 

stude13

New Member
May 28, 2008
404
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0
north bend wa.
you can start the motor, let it idle, then squirt some starting fluid ( wd40 ) at the junction of carb tube and engine, try wiggling the carb at the same time. if there is a leak the engine will rev up.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
236
63
up north now
you can start the motor, let it idle, then squirt some starting fluid ( wd40 ) at the junction of carb tube and engine, try wiggling the carb at the same time. if there is a leak the engine will rev up.
...or want to quit, depending on what you use....either way it will tell you if you have a leak without removing anything.
 

Saddletramp1200

Custom MB Buiilder
May 7, 2008
1,444
46
48
Houston, Texas
The safest way is a spray bottle with water in it. With the engine running spray around the carb. NOT into the air cleaner! If there is an air leak it will bog down. (c)
 

Mopedamauter79

New Member
Mar 31, 2008
254
0
0
Ottawa
I have ran the engine in the rain before and it never bogged or stalled. I will try out the suggestions when I feel better. Took a nasty wipe out yesterday afternoon.
 

Mopedamauter79

New Member
Mar 31, 2008
254
0
0
Ottawa
The carb has no gasket at all and that is probaly the source of the air leak. I'm transfering the motor to a new frame that's smaller tubbing so it will be easier to install. The reason for this is the back end of the frame is not even. The back wheel wont line up properly at the bottom and the top by the brakes. If it's lined up at the bottom it's off center at the top. I tried different wheel's with the same result..There doesn't seem to be any damage to the frame that I can see...
 
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