DescriptionThis video provides step-by-step repair instructions for replacing the choke thermostat on a Briggs and Stratton small engine. The most common reasons for replacing the choke thermostat are when the engine is hard to start or won’t start at all.
All of the information for this choke thermostat replacement video is applicable to the following brands:
Briggs & Stratton, Toro, John Deere, Lawn Boy
Tools needed: flat-head screwdriver, hammer, 7/16th inch socket, Phillip-head screwdriver, 5/16th inch socket or nut driver, 3/8th inch socket or nut driver, pliers
Step-By-Step Instructions1
Before you replace the choke thermostat on your engine first make sure the engine and muffler have cooled.
2
Next, you should remove the wire and boot from the spark plug to prevent the engine from accidentally starting.
3
We recommend performing this procedure with little or no fuel in the tank.
4
Use a flat-head screwdriver and hammer to bend the muffler mounting bolt locking tabs out of the way.
5
Now use a 7/16th inch socket to loosen and unthread the bolts.
6
Pull the muffler free of the cylinder.
7
If still intact, remove the old choke thermostat.
8
Before you install the new choke thermostat confirm that the locking tab plate, bolts, gasket and heat shield are in place on the muffler.
9
Now position the provided inner gasket and the new choke thermostat on the muffler along with the outer gasket.
10
To allow proper alignment of the choke thermostat arm, we recommend removing the blower housing.
11
To do this, use a phillips-head screwdriver to unthread the mounting screws securing the engine cover.
12
Next, release the starter rope from the retainer.
14
Now use a 5/16th inch socket or nut driver to remove the screws securing the fuel tank.
15
Use a 3/8th inch socket to remove the mounting bolt securing the tank to the side of the engine block.
17
You can now remove the 3/8th inch bolts securing the blower housing.
18
Pull off the blower housing and oil dipstick tube.
19
Now apply some anti-seize to the threads of the muffler mounting bolts.
20
Position the muffler assembly on the cylinder, making sure the choke thermostat arm is inside the air vane hook.
21
Thread the mounting bolts and torque them to seven-and-a-half foot pounds.
22
Bend the locking tabs in to prevent the bolts from unthreading.
23
Be aware that the thermostat arm needs to be aligned between the markings on both the front and side of the air vane hook.
24
Replace the blower housing making sure the attached dipstick tube is inserted into the sump.
25
Thread the mounting bolts to secure and torque them to seven-and-a-half foot pounds.
26
Confirm that the spacer is in place on the fuel tank then reposition the tank on the blower housing.
27
Replace the bolt and mounting screws to secure.
28
Realign the engine cover.
29
Rethread and tighten the mounting screws.
30
Depress the bail arm, extend the starter rope and secure it in the retainer.
31
With the repair completed reattach the wire and boot to the spark plug refill the fuel tank and your engine should be ready for use.