# Not Priming



## King285

Engine is a '96 Tecumseh HSK850, 2 stroke 5hp on a 21" single stage MTD (Mastercraft brand) mod. no. 31AE160 - 515.

Can't get the primer to draw fuel into the carb.

No apparent blockages in fuel tank or line. Good stream of fuel.
Primer bulb and hose show no damage. Rubber not stiff/cracked. Can hear air being pushed into carb.
Carb has been cleaned using carb cleaner and compressed air, twice, as it was very gummed. Float not sticking and needle well seated. Bowl o-ring in good condition. Gaskets ok.
Runs when fuel is poured into carb intake or spark plug hole. But dies once that fuel has burned off.

What am I missing?


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## Jackmels

There is no gas in the carb bowl. Must be a blockage in the fuel line, or the gas cap isn't venting.


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## King285

Good amount of gas in the bowl. Just can't draw more when priming for starting.
Tried priming with gas cap on, off, loose. No luck.


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## Shaw351

Check these....
Float not set right, not enough fuel in bowl to push fuel into intake. 
Idle / main needle screws are seated and not allowing fuel to flow.


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## Jackmels

The Primer Bulb Pressurizes the Carb bowl, Forcing gas through the main jet. The passage may be blocked. Work a piece of lock wire or bread tie through the primer nipple on the carb. Or Possibly the bowl gasket is not sealed/seated, and the bowl cannot pressurize due to that.


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## e.fisher26

Is the bowl gasket ok?


-efisher-


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## LouC

Sometimes the primer itself gets cracked from age and will not pressurize the fuel line. I had this on my 98 Toro/Suzuki....after about 15 or so years...Disconnect the hose that goes from the primer to the carb to make sure its actually is making pressure.


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## JackB

Dont know that particular machine but some carbs the screw that holds the bowl on is also the main jet and it could be clogged. If it has that type the end of the bowl screw will have a hole in it and then there would be a hole drilled across that connects just above the threads.


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## JR-80

King285 said:


> Engine is a '96 Tecumseh HSK850, 2 stroke 5hp on a 21" single stage MTD (Mastercraft brand) mod. no. 31AE160 - 515.
> 
> Can't get the primer to draw fuel into the carb.
> 
> No apparent blockages in fuel tank or line. Good stream of fuel.
> Primer bulb and hose show no damage. Rubber not stiff/cracked. Can hear air being pushed into carb.
> Carb has been cleaned using carb cleaner and compressed air, twice, as it was very gummed. Float not sticking and needle well seated. Bowl o-ring in good condition. Gaskets ok.
> Runs when fuel is poured into carb intake or spark plug hole. But dies once that fuel has burned off.
> 
> What am I missing?


I discovered by accident that you don't need a primer bulb. Just tip snow blower all the way forward and let it sit for a minute. Now tip it back, choke it and it will start. Seems to work every time.


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