Tecumsesh 2hp horizontal

That engine is an AV520 series Tecumseh, they came with different trim over the years.

The spec sheet says 24:1 on oil mix.

Because it is a reed valve 2 stroke with a diaphragm carburetor it will operate in any orientation as long as the fuel keeps flowing to the carburetor.

It would be a bad idea to re-locate the carburetor on that type of engine. You could lean the cylinder forward parallel to the front frame tube very easily.

Heck, you could mount it upside down with the carburetor straight up if you wanted to.

AV520 Spec Sheet

AV520 Blueprint

Good luck with your project.

B.
 
Ok, I just bought this little beauty and now I'm looking for info on one of these while I wait for it to come. Have any of you seen one or had one of these engines?

This is suppose to be the model:
Tecumseh model 9B28B518830 2hp horizontal engine

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I can't tell yet by the pictures, if the carb could be move some or not.
Just for your information Bud the engine in the pictures is a Jacobsen itll be 3-5hp. Im building a bike now that uses the same motor, its my second build with a jacobsen.
 
check my pennysworth build in the btr section or my 40mph club build in the dyi section the FD build in the DYI section does 42mph and gets 175-180 mpg
 
That engine is an AV520 series Tecumseh, they came with different trim over the years.

The spec sheet says 24:1 on oil mix.

Because it is a reed valve 2 stroke with a diaphragm carburetor it will operate in any orientation as long as the fuel keeps flowing to the carburetor.

It would be a bad idea to re-locate the carburetor on that type of engine. You could lean the cylinder forward parallel to the front frame tube very easily.

Heck, you could mount it upside down with the carburetor straight up if you wanted to.

AV520 Spec Sheet

AV520 Blueprint

Good luck with your project.

B.
The AV 520 has a square head the jacobsen as youll notice has a round head and if ya peek inside youll find a very HIGH domed piston redline is 4500rpm stock on the jacobsen. I run mine @ 50:1 using a synthetic 2 smoker oil
 
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I bought a 2 cycle lawnmower at a Firestone store in 1959, looked a lot like your motor. When the bushing thats the bottom main bearing gets worn or the crankshaft seal leaks then its all over for the motor, hard to get started. If you had a small flywheel to take the place of the lawnmower blade that would help it idle. I cast a small extension for the carb so it would be the same when the engine was on its side, didn't work.
 
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