Rockwell 440cc and a kenbar streaker?

Thepartsguy

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Back in 2023 I had a giant blue buggy with a 400cc Rockwell JLO engine. Big piece of junk never worked out.

Sold that buggy and moved on. NOW it’s 2026 and I’m scrolling marketplace and what do I spot? A cut up scorpion whip snowmobile for $40

I have a streaker and the Kohler on it now is a shiny piece of crap that lacks power and the kart is becoming less and less fun to ride due to it being unbearably slow. Maybe we can fix that?IMG_6720.jpeg
 

Thepartsguy

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Insert me cutting up the rest of the sled to snag the engine/clutch in the guys driveway and he even let me use his tools!

I did not know what I was buying it could have had a hole blown in the mag side piston it could have been missing parts it was $40 AS IS.

(The sled set for 30+ years and the engine was locked up. Pull cord would not budge) that was the description of the sled I had to work with. I messaged him and said I don’t care about condition I’ll be out whenever works best for him!

The sled was in a trailer 4 miles down the street and 20 minutes after messaging him I was back home get to work on what i just payed $40 for.
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Thepartsguy

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So off with it‘s heads :LOL: Then the wd30A Walbro was unbolted exhaust off and gut the wiring. Pullstart off etc..

The bores pistons and everything looked amazing so I could not figure out why it was locked? A small piece of wood and a rubber mallet bang on the mag side piston ONCE and it unstuck instantly! ZERO EFFORT.

Now i’m in cleanup mode. All the gunk and grime gets wire brushed and I’m debating silver paint and making the engine look flashy as i don’t want a grease pile of a 440 twin on a bright red gokart.

The kicker? .30 over wiseco’s in both bores and a very very clean WDA-30A Walbro! These stock 440’s make 30-40hp and lightly modified one can push 40-50hp
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Thepartsguy

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Not gonna go crazy painting after all it cleaned up well.

Next onto the clutch. Clean it up and hit it with a bit of paint.
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Thepartsguy

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Degreased and painted the secondary clutch housing. The picture sucks but it cleaned up and painted very very nice!

The points on the engine did not need filed and I was told this thing set 30 years! Both plugs have bright blue spark!

I will finish and clean up the actual driver and driven pulley and then I need to mount the engine to anything I can as it has some killer compression.

I can’t actually pull it over reliably until it’s mounted solid to something. But with how clean everything is I’m willing to bet it’s a stout runner.
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Thepartsguy

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I’m so tired of grease and dirt that’s why I made a point that the only time I will deal with it anymore is to clean it off so I can have a non greasy part.


I have to do a general clean up of the driver/driven still and then mount the engine to something so I can hear it run.

After that there is nothing left. I have to yank the kart out of the back of the garage and start mounting the engine. Once it is mounted I’ll need plate steel to mount the driven.

Once the engine is mounted to the kart I’ll have to cut up the stock snowmobile exhaust and make a lot manifold or hunt marketplace for a stinger style expansion chamber.

Mounting the engine will be easy. The driven could be tough and the exhaust could be tough.
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Hellion

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I think Mustie refurbed one of those engines so I have a tidbit of familiarity with it.
 

Thepartsguy

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The driven/driver got a full corse sand job and now the belt doesn’t have the job of beating all the rust and shining the sheaves up. Everything is done until the engine is mounted on the kart.

I want to get plate steel before I even pull the Kohler off the gokart. Once I have plate steel to work with I will mount the 440cc and then work on mounting the driven pulley and hooking up the standard 420 chain.

After the engine/driven are mounted with the chain hooked up I will have to make a log manifold that doesn’t stick directly into my back.


Now that everything isn’t a grease pit I can at least work with it and not end up a filthy wreck.

Going on day three of owning this engine or day two? Lost track. But I want to also work kind of quickly. I have seen a lot of snowmobile swapped karts and they are all rusty grease pits.

I would like to have a clean simple setup so that’s what I’m shooting for. Although I’m no perfectionist.
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Thepartsguy

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I really hope this site on the backend is refreshing itself and the admin/mod isn’t babysitting it having to refresh it 20+ times a day. IMG_9212.jpeg
 
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