Mantis tiller no start

heyhi

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Long shot. You guys helped me rebuild my engine for a batavus. At that point I figured I could fix any 2 stroke. I was wrong.
My dad has a 7920 mantis tiller. It's not a bike it's a little two stroke that digs. Couldn't get it started.
I pulled apart the carburetor and cleaned it. There's a spring that opens and closes the throttle. While I was taking it apart it unwound And I thought I broke it so I ordered a new one. I put the carburetor back and it started right away but it was very high idle. When the new spring came in I took the carburetor off and took the spring off only to see that I just had to wind it up a little bit to get tension. Put everything back together now it's not starting at all. Do you guys have any experience with these? There's three adjustments screws, which of course I touched every one of them, But I don't know if that stops it from starting.
I checked and it has spark and compression
 

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heyhi

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You can see the spring where the idle screw is
 

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heyhi

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How much of that carb did you take apart?
I pretty much took the whole carb apart. Except for the primer bulb.
I ordered a new carburetor.
Hipa C1U-K54A Carburetor for Mantis Tiller 7210 7222 7222E 7222M 7225 7230 7234 7240 7920 7921 7924 7925 7228 Cultivator C1U-K82 Maintenance Kit https://a.co/d/d8e8dDf
it's pretty cheap. But I wish I could have fixed it without ordering that
 

machanic

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Short of replacing the primer bulb those carburetors are virtually unrebuildable they have incredibly small passages machine into the block with very fine screens for straining out contaminants once they get varnished up or corroded from today's wonderful gasoline they cannot be clean. The three screws are high fuel ratio low fuel ratio and idle speed idle speed one is obvious it goes to the throttle linkage the other two are usually labeled with an l and an H
 

Chainlube

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I pretty much took the whole carb apart. Except for the primer bulb.
I ordered a new carburetor.
Hipa C1U-K54A Carburetor for Mantis Tiller 7210 7222 7222E 7222M 7225 7230 7234 7240 7920 7921 7924 7925 7228 Cultivator C1U-K82 Maintenance Kit https://a.co/d/d8e8dDf
it's pretty cheap. But I wish I could have fixed it without ordering that
How was the diaphragm? Was it hard to bend or soft and pliable? I've rebuilt many of them, the only part I don't recommend for a layman is the welch plugs. Put them in the ultra sonic for an hour, done.
 

machanic

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How was the diaphragm? Was it hard to bend or soft and pliable? I've rebuilt many of them, the only part I don't recommend for a layman is the welch plugs. Put them in the ultra sonic for an hour, done.
Yes there is the ultrasonic cleaner, not every one has one but comes in handy when a superior cleaning is required.
 

heyhi

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How was the diaphragm? Was it hard to bend or soft and pliable? I've rebuilt many of them, the only part I don't recommend for a layman is the welch plugs. Put them in the ultra sonic for an hour, done.
The diaphragm were pretty soft.
 

GW's Motorized

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You might check for a vacuum leak. My dad had a harbor freight auger that was a pain to start and ran like crap. He ended up giving it to me and buying a new one. All it was was a loose intake manifold. I tightened it up and it ran beautifully. I then swapped the engine onto my two stroke scooter(it has way too much power now). I haven't fired it up in about a year though.
 

heyhi

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How do I see if there's a vacuum leak without starting it?
 
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