Briggs and Stratton Auto Choke on Toro Problem

I don’t seen any adjustments I can make to the choke spring. it is attached to all plastic.
Here are some pics.
 
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Sorry here they are.
 

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Here is a better video of the problem, it only happens when the mower is cold or sits for around 20-30 min. It happens as soon as the blades engage the choke goes crazy
 
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The choke goes gar gars because when the blades are engaged the throttle opens up and more air is sucked past the butterfly which tends to close the choke , which stretches the spring which then pulls the choke back and the air pushes it closed , the spring stretches and thus they cycle continues.
Cut 2 turns off th short ens of the spring then bend the next one out 90 deg to fit over the pin
 
bertsmobile1 said:
The choke goes gar gars because when the blades are engaged the throttle opens up and more air is sucked past the butterfly which tends to close the choke , which stretches the spring which then pulls the choke back and the air pushes it closed , the spring stretches and thus they cycle continues.
Cut 2 turns off th short ens of the spring then bend the next one out 90 deg to fit over the pin
Click to expand...

Just cut the spring to shorten it but still no change. I cut another 2 off and still no change unfortunately.

Any other ideas before I fire the parts cannon at this?
 
Does anyone think this is a governor issue? I just came across this video and it looks like the same thing is happening.... Fast forward to 6:05.

 
My neighbor gave me his non-starting TB PW 020381 with Briggs 12S912, same as above video. I found exactly the same thing as above. I needed camshaft, gov/oil slinger, timing gear, gaskets - it was over $100 in parts. I said screw it, parted engine out and found another for good pump PW. But if all you need is gov/oil slinger and gasket - would be worth it.
 
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Update, new choke spring cam today and still same issue.

After that I took the engine off and took off the crankcase cover to inspect the govenor. Everything looks fine inside. Gonna order a new gasket and put the engine back in i guess...

This is turning into a huge mystery and getting frustrating.. Any other ideas?
 
I’ve worked on dozens of these units and don’t understand what is going on. I’m going to have to get to the shop to see what a new unit looks like. Something tells me you don’t have something hooked up correctly. Will get back to you as soon as possible.
 
Rivets said:
I’ve worked on dozens of these units and don’t understand what is going on. I’m going to have to get to the shop to see what a new unit looks like. Something tells me you don’t have something hooked up correctly. Will get back to you as soon as possible.
Click to expand...


I really appreciate that. I did buy this mower used a few weeks back so anything is possible at this point.
If you need me to take more pics of something specific let me know and I wil upload then ASAP.
 
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