Lawn Boy Briggs and Stratton 124t00 Cold Start Auto Choke

[polyglot0727]

Lawn Boy walk-behind with a 6.5HP Briggs and Stratton with autochoke/readystart. Engine model# 124t050216b1. Wouldn't start. Confirmed good spark from plug, new plug. Replaced fuel, oil, and air filter. Rebuilt carb with kit. Lawn mower will not cold start. Can manually open auto choke valve just a crack, and mower starts and runs fine. When I release air vane of autochoke, choke valve comes to rest, completely closing butterfly valve and stalling engine. Once the mower has warmed up, it starts without manually opening the choke valve. Am I looking at a problem with the thermostat here, or could it be something else? Is there any way to adjust the choke/thermostat? FYI. Replaced choke spring on autochoke as well.

 

[ILENGINE]

The thermostat is to hold the choke open for warm restart. I thing the problem is in the air vane that is supposed to open the choke when it starts cold.

 

[vogtrj]

Make sure the air vane isn't fed through the thermostat like it is in the picture. A mechanic had done this to the one I was given causing exactly what you are describing (the reason the mower was replaced by a colleague and given to me). Attached is a picture of how it was when I first took the shroud off. It's apparently a common occurrence. If it's like this, move it out and it should solve your problem. The air vane should be moved to the left as it is oriented in the picture. The rounded side of the thermostat top is adjustable if needed.