2 cycle Twin Tecumseh

[karl]

I got two nearly identical toro s200 blowers, so I pulled the motors.

Thinking of doing this.

The motor that spins backwards will have the timing re-adjusted. The flywheel fins are straight, and each motor will have its own shroud, flywheel, coil, ect.

Cut the shafts down a bit, and use a sprocket as a coupler. This will get the motors closer together.

Good Idea?

 

[Whitetrashrocker]

You will need a reverse cut cam for the backwards engine.

The flywheel could have a new keyway broached at the proper spot opposite TDC.

I think the cam is the biggest issue.

 

[anickode]

You will need a reverse cut cam for the backwards engine.

The flywheel could have a new keyway broached at the proper spot opposite TDC.

I think the cam is the biggest issue.

They're 2 strokers. No cam to worry about. Spin it backwards and it'll run backwards.

your plan to close-couple two air cooled engines back to back is liable to cause some cooling issues if they're too close together.

And if the fan housings are designed to channel airflow based on a clockwise flywheel rotation. It would work backwards, but not as efficiently.

If you were to remove the recoil from one and make an adapter to couple the shaft of one engine to the flywheel of the other, and index them so they were on opposite strokes, it could simplify things a bit, perhaps.. Might still have cooling issues.

Personally I would just mount them next to each other with their own clutches and connect both to a jackshaft.

Or set it up as 2 separate one-wheel peels. Have the traction of a live axle with the handling of a differential.

 

[Whitetrashrocker]

They're 2 strokers. No cam to worry about. Spin it backwards and it'll run backwards.

That's a horse of a different color. Didn't realize they were 2 stroke.

 

[landuse]

Won't the one engine always be slower or faster than the other? I have never known two engines to run at the same RPM's, no matter how hard you try. And with them stuck together that might be a problem

What do i know though?

 

[anickode]

Won't the one engine always be slower or faster than the other? I have never known two engines to run at the same RPM's, no matter how hard you try. And with them stuck together that might be a problem

What do i know though?

Um... Sticking them together resolves that. Otherwise we'd all have giant sized 1 cylinder engines in our cars.

 

[Desertduler]

Just mount them up just like they back in the 60's. Twin engine karts were common then like this one for example.
https://www.youtube.com/watch?v=_nLzvx2RT3k

 

[mckutzy]

Won't they just synchronize in rpm after they rev up, one will retard the other when one is about to take over, And so on?

 

[Desertduler]

Won't they just synchronize in rpm after they rev up, one will retard the other when one is about to take over, And so on?

Yes, exactly.

 

[Jasonrk99]

Personally I would just mount them next to each other with their own clutches and connect both to a jackshaft.

Or set it up as 2 separate one-wheel peels. Have the traction of a live axle with the handling of a differential.

Agreed! Run two separate clutches. I’m also doing a Tecumseh two stroke kart. If I can find another Snapper Lawnmower with a two stroke Tecumseh TVS840, the kart will be twin engine. Mine have 7/8” shafts however.

 

[karl]

I would run two separate engines. But thats common, and a pain to start both engines.

If I ran duel on the back with dead axle, I would still need to make a motor run backwards. Making a backwards pull start might be difficult.

I need to do some thinking.

Thanks for all the input!

 

[Desertduler]

I would run two separate engines. But thats common, and a pain to start both engines.

If I ran duel on the back with dead axle, I would still need to make a motor run backwards. Making a backwards pull start might be difficult.

I need to do some thinking.

Thanks for all the input!

If you do indeed connect the two crankshafts together then I would phase the crankshafts connecting rod journals 180 degrees of each other. One at T.D.C. and the other at B.D.C. Just like a twin cylinder two stroke engine. I would like to see you do it and come up with something different. At least you are thinking outside the box which I like.