Throttle return spring

samp.98

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I have a short, simple, and stupid question. What is the purpose of the small throttle return spring? My mower is surging and I noticed that mine was missing. Can that cause surging? I have noticed them on every small engine carburetor I’ve ever seen, and never actually known what they are for. (I’m going to get a new spring tomorrow regardless)
 

bertsmobile1

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There are no return springs on throttles
The throttle control pulls the governor arm on via a spring and the governor mechanism inside the engine pushes the throttle off.
If you are talking about that long spring that goes around the throttle rod ( bit between the governor arm & the throttle butterfly ) it is there to dampen down the response so you don't get a hysteresis reaction when the governor moves the throttle.

Surging is ALWAYS CAUSED BY INSUFFICIENT FUEL FOR THE VOLUME OF AIR
So either the carb is not putting enough fuel into the mix or air is entering the engine after the fuel has been added.
 

keakar

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good question and i think, but dont know 100% for sure, i think its just there to hold it in place because it doesnt seem to serve any other function and i find it disconnected and/or broken on a lot of mowers yet they run fine without it
 

keakar

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There are no return springs on throttles
The throttle control pulls the governor arm on via a spring and the governor mechanism inside the engine pushes the throttle off.
If you are talking about that long spring that goes around the throttle rod ( bit between the governor arm & the throttle butterfly ) it is there to dampen down the response so you don't get a hysteresis reaction when the governor moves the throttle.

Surging is ALWAYS CAUSED BY INSUFFICIENT FUEL FOR THE VOLUME OF AIR
So either the carb is not putting enough fuel into the mix or air is entering the engine after the fuel has been added.
he is talking about that long teeny tiny itty bitty spring threaded onto the throttle linkage arm that connects to the governor linkage arm on the single cylinder engines
 

bertsmobile1

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good question and i think, but dont know 100% for sure, i think its just there to hold it in place because it doesnt seem to serve any other function and i find it disconnected and/or broken on a lot of mowers yet they run fine without it
it is there to dampen down the response so you don't get a hysteresis reaction when the governor moves the throttle.
 
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