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Tecumseh/YardMachines won't start


jzinckgra's Avatar
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ME

04-11-05, 08:02 AM   #1  
Tecumseh/YardMachines won't start

I have an ~3 year old YardMachines push mower with a 3.5hp Tecumseh engine. The mower was left under our deck by the people who sold us the house and it looked pretty neglected. I put fresh gas in, new spark plug, cleaned the carb (may still be plugged though). The primer bulb doesn't seem to do anything but push air. I looked for cracks in the rubber, but don't see any. I put a little gas in the plug hole and the mower briefly started then quit. It seems to me the carb is not getting fuel,probably due to a clogged jet. What's the best way to clean the carb? I tried soaking in gas for a few minutes, but I guess that didn't help.
One other question I have is regarding the throttle. I'm not sure if this is a fixed speed mower or not. On the engine there are a couple springs that attach to the carb inlet and when I manually move the lever near the carb, it opens and closes the "flapper" on the inside of the carb. Isn't this the choke? Anyways, there is no throttle lever up on the handle, which is why I assume it is fixed speed. Just not sure what the point of the flapper is. Does it open/close on its own? Sorry, I don't have the serial # of the engine, but can check on it later. Thanks.

 
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04-12-05, 01:10 AM   #2  
The "flapper" you talk about is the throttle plate. This engine has no choke. The purpose for it is to control the amount of air the engine can take in. Your problem is that the carburetor needs a good cleaning. Remove the bolt that holds the bowl on and clean the tiny holes in it. There are 4. 2 oppose each other near the head of the bolt, one goes down the center, and one is in an unthreaded section near the end. This one is tiny and usually the source of the problems. In your case, they may all be plugged. You can use a wire and spray carb cleaner to do this, and if a better cleaning is needed, get a quality bath type cleaner for it and a rebuild kit.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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04-12-05, 07:00 AM   #3  
Thanks for the response. So would this engine have had a throttle control to operate the throttle plate? There isn't one on there now.

 
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04-12-05, 10:51 AM   #4  
Azis
The lever you mentioned near the carb may be your throttle. Or it could be there is no throttle control. If your air breather shroud or engine shroud has a rabbit and turtle for fast slow or similar, then you should have a controlable throttle. It doesn't control the throttle valve directly tho, it basically changes spring tension on the govenor lever thus changing the throttle valve.
The primer bulb is basically in place of a choke. If it does not work correctly it will be hard starting.

 
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04-15-05, 03:40 PM   #5  
well, I bought some carb cleaner and cleaned the carb. The small bolt at the bottom of the bowl was definately clogged. I cleaned all the holes out and still, it won't start. If I shoot a little carb cleaner in the carb, she'll fire then quit. Still not getting gas. What I noticed was when I took the bolt out of the bottom of the carb, gas started leaking out. I played around a little more and noticed that when I lifted the float, the gas stopped and when I released it (and the float dropped), fuel started flowing again. I think what is happening is when I put the bowl back on and tighten the bolt, it is compressing the float and prematurely shutting off the flow of gas before the bowl gets full. ALso, when I try pressing the primer bulb, there just isn't any priming going on- only air. Where should I go from here? Thanks again.

 
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04-15-05, 09:38 PM   #6  
float

raise the float level. Let some fuel in>

S/T

 
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04-15-05, 10:55 PM   #7  
The bowl won't push the float up any higher than it should be. I think you're going to need to remove the carb, disassemble it and soak it in a bath type carb cleaner and install a rebuild kit to get this one going again. I'm betting the o rings on the fuel nozzle are also gumed up and need to be replaced.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
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