Can you put a pushmower engine on a lawn tractor?

I have a 20 horse engine that doesn't run and I was wondering if I could put a pushmower engine in it's place

are u going to be running the deck?

This one guy on you tube did that on a murray he had - pretty much for buzzing around with . I can tell you that owning a few stock 5HP tractors, you wont be able to run a deck with a 3HP motor - 5HP can barely handle it.

No deck.it's the same mower as in my other post. It's only gonna be used for fun

Your going to need a cast iron flywheel or a heavy pulley to put on the crankshaft since its a push mower engine. It will kick back with out it.

i found that out the hard way, tried to start it w/out the blade and nearly broke my wrist. im not really concerned with this mower anymore as im working on my murray lawnchief RER. its been sitting foir a couple of years and i need to get it running.

just use a pushmower engine for riding around on a flat surface because it is so limited on power

I don't understand what happens when you try pull starting it without a blade. I know the engine was designed to have a relatively heavy flywheel (blade) on the output shaft, just didn't know what kind of affect it would have with it missing. Does the engine jerk back in reverse rotation when it doesn't start because of the compression stroke?

the pulley would be enough weight for it but you wont have torque but it would be good for speed with i good pulley swap

3hp in a tractor built for 20hp is hardly going to be able to move it.

In a smaller RER it would work,