B&S rebuild, new carb, won't start without starting fluid

Scrubcadet10

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  • / B&S rebuild, new carb, won't start without starting fluid
So does the choke plate ever close? If so, when?

Thanks everyone for the input so far.
on these engines the throttle plate should never fully close... if you can, post a picture of the carburetor and the linkage on your mower.
 

Fish

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  • / B&S rebuild, new carb, won't start without starting fluid
The engines came with a choke or a primer capability, but with an aftermarket carb, who could know? Post a link to the carb that you bought, the old one, and the air filter assy.
 

Fish

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  • / B&S rebuild, new carb, won't start without starting fluid
I should be able to see a gush of fuel pop up? Where would I see this? can I see it with the air filter on?
No, you take the air filter off and look into the throat of the carb and watch, you should see a pulse of fuel pop up into the throat.
 

hcliffe

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  • / B&S rebuild, new carb, won't start without starting fluid
on these engines the throttle plate should never fully close... if you can, post a picture of the carburetor and the linkage on your mower.
Here are pics., Let me know if you need better, closer etc. Thanks!
 

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Fish

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  • / B&S rebuild, new carb, won't start without starting fluid
Here it is behind the white plastic baffle.
carbthroat 001.JPG
 

Fish

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  • / B&S rebuild, new carb, won't start without starting fluid
The plate that you are seeing is the throttle plate. Put up a pic of the backside of your air filter assembly and the gasket. You will notice the indentations in your old gasket, that is the path of the air pulse to the carb to prime it. If it doesn't seal well, then you won't prime the carb.
 

Scrubcadet10

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  • / B&S rebuild, new carb, won't start without starting fluid
All of your throttle linkage appears correct.
What i outlined in red is your throttle shaft and throttle plate (also called a butterfly valve, sometimes) it should sit a wide open (like it is) when the engine is not running, and close down to a little less than half way open when running.
What i outlined in green is your emulsion tube, which the main jet screws into, you should see fuel squirt out of it when you press the primer bulb.
what i circled in purple is the hole for the air impulse into the fuel bowl, which then push fuel out of the main jet.
CARB45.png

Here is the back of your airbase/primer assembly.... when you push the bulb, air follows the path i outlined in blue, and comes out the hole i circled in blue, the hole corresponds with the the hole that i circled in purple on the carburetor.
primer.png
 

hcliffe

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  • / B&S rebuild, new carb, won't start without starting fluid
Here are pics of the air filter housing.
 

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hcliffe

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  • / B&S rebuild, new carb, won't start without starting fluid
All of your throttle linkage appears correct.
What i outlined in red is your throttle shaft and throttle plate (also called a butterfly valve, sometimes) it should sit a wide open (like it is) when the engine is not running, and close down to a little less than half way open when running.
What i outlined in green is your emulsion tube, which the main jet screws into, you should see fuel squirt out of it when you press the primer bulb.
what i circled in purple is the hole for the air impulse into the fuel bowl, which then push fuel out of the main jet.
CARB45.png

Here is the back of your airbase/primer assembly.... when you push the bulb, air follows the path i outlined in blue, and comes out the hole i circled in blue, the hole corresponds with the the hole that i circled in purple on the carburetor.
primer.png
Great diagram and explanations, thanks!
 
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