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Cub small engine swap.

Posted: Fri May 29, 2020 2:45 pm
by Spencerpearson31
So I know that there is a small move to do the Cubota engine swap. But I have a question on something similar. If my engine were to go bad for what ever the reason. And I made engine frame brace. As well as put something like a 14hp engine on a plate with jack shafts to the trans and all the sheet metal back on. Do you think it would get good or bad looks from others in the show if I took it. The only reason I ask this is simply cause even though I would love to keep a cub looking as it did from factory. I use mine in the garden and other things. And want to take to shoes like normal. But if I had a engine problem and could not locate a fix. Would it then be inappropriate to do that swap and still take to shows. Or would you think it would be most likely welcomed for the creative nature. Just thoughts as that’s what I would think if I saw one.

Re: Cub small engine swap.

Posted: Fri May 29, 2020 3:05 pm
by Waif
Guessing it would matter if a particular show was juried for stock configurations only. Or if modified , (and how modified) were allowed.

Re: Cub small engine swap.

Posted: Fri May 29, 2020 3:42 pm
by Eugene
Most small lawn mower type engines operate at 3600 RPM with their maximum torque some where around 2200 - 2400 RPMs.

If you think it's a good idea, go for it.

If I saw it at a tractor show I would scratch my head and wonder why. Then have a really great conversation with the tractor owner.

Re: Cub small engine swap.

Posted: Fri May 29, 2020 5:54 pm
by inairam
You are not going the have the correct torque or RPM to make it practical. It will move but I do not think it will be useful. Horsepower is a made up term by James Watt to make a quick way to compare different engines. You have to look at the components of HP - torque, and RPM when picking an engine for an application. A Ferrari engine and a boat engine may both produce 500 HP but you probably will not be happy if to switch them. That is because the torque curve and operating RPM are very different.

To go to your original question - if your engine dies there are enough cubs, power units, and parts tractors out there to get a C60 engine.

Re: Cub small engine swap.

Posted: Fri May 29, 2020 6:03 pm
by Spencerpearson31
Ok get thank you all for the input. I would still want to keep this one original. And fix the motor. I just was thinking about it while in a break from splitting the tractor to fix a bent transmission shaft and throw out bearing

Re: Cub small engine swap.

Posted: Fri May 29, 2020 10:35 pm
by Ike
The idea has been done on a bigger tractor than a Cub. I remembered this video I saw years ago.

Re: Cub small engine swap.

Posted: Fri May 29, 2020 10:52 pm
by Spencerpearson31
Yeah that’s where I first thought about it . A while back as well. I think that is why I had thought it may work for the cub.

Re: Cub small engine swap.

Posted: Sat May 30, 2020 5:58 am
by inairam
They are moving the Massey around but they are not putting a big load on it. I guess the bailer put the biggest load.

They have a good reduction between the sprockets (at 2.27 min) about 3-4 to 1 reduction so they are going into the trans at 900-1200 RPM.

I am sure the performance of the tractor is very different than the original but they are moving it around and getting some work out of it. I do not think they made 250000 Massey Harris 33s. They had a lot fewer options to re-engine or get parts so this project worth the effort.

There are a lot of c60s around.

Re: Cub small engine swap.

Posted: Sat May 30, 2020 7:03 am
by Gary Dotson
I see a lot of creative stuff at shows and it's all fun to look at. Some of it makes no sense at all, but it's still neat to look at. Someone once asked George Willer why he did a certain thing and his answer was "because I could". He made quite a few useless creations and, yes, they were fun to look at. If everyone brought the same items to the shows, it would soon get boring. Go ahead, build something crazy and take it to shows and show it to the world.

Re: Cub small engine swap.

Posted: Sat May 30, 2020 9:00 am
by Spencerpearson31
I thought it would be nice to see creative stuff. Like I say I have a cub and going through it front to back and it runs good. But for those few that make it to the scrape yard. That’s what I was thinking. The hole why would you scrape it thought. Why not fix it or if you can’t fix the original power plant. Then why not do what that guy did. If it runs the cultivator and pulls a disc then it’s a positive out come. May be slow but beats doing it by hand lol

Re: Cub small engine swap.

Posted: Sat May 30, 2020 1:04 pm
by SONNY
Saw a 185 lo-boy with a Ford 302 stuffed in it and didnt notice it til some guy started laughing at it ---THEN I saw what was up! The guy did a pro-job and got the hood back on, front end all on and painted just like regular lo-boy with yellow engine.
IF you have the money and some time to waste ---anything is possible. Also you need access to expensive machines to make parts to connect the stuff together!

Re: Cub small engine swap.

Posted: Sun May 31, 2020 2:34 pm
by Spencerpearson31
Yeah I could see that having some money in it. I love seeing things like though. It gets my gears to turning . Trying to figure out how that was done . And the question that follow.

Re: Cub small engine swap.

Posted: Sun Jun 07, 2020 12:05 am
by BigBill
I been debating this engine swap in my loader project. Maybe a diesel.

I once brought a restored ‘72 suzuki TS250 to a bike show once. The guy who laughed didn’t even have a bike, these were early dual sport trail bikes that everyone had one. I don’t like people who laugh at my mule, it hurts his feelings, lol

Re: Cub small engine swap.

Posted: Sun Jun 07, 2020 11:43 am
by 47fivewindow
At shows I am always interested in the ways folks have used offbeat fixes. You can only look at so many perfectly restored H tractors. Concerning the RPM difference, if a belt drive is used a two to one pulley ratio would put you in the correct range.

Re: Cub small engine swap.

Posted: Tue Jun 09, 2020 5:56 am
by BigBill
Ike wrote:The idea has been done on a bigger tractor than a Cub. I remembered this video I saw years ago.


This is cool but an old Buick straight eight engine with a peerless governor would be neat.