I think it's interesting they redesigned the idle jet positioning. Anybody know if they increased the main jet size on the new design? What I see the most is the main jet gets partially or fully clogged and it happens often. I used to use a micro-drill to clean the existing jet size but due to callbacks, I took Steve's advice (Steve's Small Engine Saloon) and everyone I get in now I drill out to 0.020. Engines run perfectly fine and it has eliminated call-backs!
2019 Troy Built mower - 09P602 engine model - Plastic Carb - Will not Start
- Thread starter MFlo
- Start date
rickpaulos
Active Member
- Joined
- Nov 2, 2012
- Threads
- 24
- Messages
- 69
Gas cap? I ran in to a similar problem where the motor started but would not rev up and stalled after ~30 seconds. The cap was previously over tightened and cut off the air intake. As gas is used, air needs to get into the tank to replace the volume of the gasoline otherwise it creates a vacuum in the tank which prevents the gas from flowing out. In this case the cap gasket was deformed from over constant tightening so I snipped some tiny wedges in the gasket to let air in and it worked great after that.
I bought a new OEM Briggs and Stratton Carb. I now have a new coil, plug, carb, clean gas. It will start but will idle then die. I sprayed starter fluid and it runs longer and dies. Eventually it will warm up and run fine. It's as if the choke does not work right. Thoughts?
rickpaulos
Active Member
- Joined
- Nov 2, 2012
- Threads
- 24
- Messages
- 69
Running way to lean? Either too much air (possible leak somewhere) or not enough fuel. About the only place lawn mower engines can have an air leak is the carb body to engine block interface. Dirt, remains of an old gasket stuck to the block, bad gasket or mounting bolts loose? Not enough fuel could be a clogged line, clogged jet, mixture out of adjustment (if it's even adjustable), float not set right, float needle valve gunked up,
The purpose of the choke is to increase the fuel:air ratio. Gets the mixture in the cylinder very rich so it's more able to ignite at startup. When the piston is going down on the intake stroke, it creates a vacuum in the carb, block the air with the choke and it sucks harder for fuel via the jet so it increases the fuel:air ratio two ways at once.
A new carb could have manufacturing debris left in it.
The purpose of the choke is to increase the fuel:air ratio. Gets the mixture in the cylinder very rich so it's more able to ignite at startup. When the piston is going down on the intake stroke, it creates a vacuum in the carb, block the air with the choke and it sucks harder for fuel via the jet so it increases the fuel:air ratio two ways at once.
A new carb could have manufacturing debris left in it.
I bought an OEM carb new. I now have a new plug, coil, gas, and carb. Now it have a hard time starting the mower. It starts, idles for a bit and dies. I sprayed starting fluid and it ran longer before it died. Eventually it started and ran fine. I have to go through the same process everytime I cold start. Seems like the choke is not working. Thoughts?
Sounds like the main jet is clogged. Where did you purchase the new OEM carb from? If not from a dealership, theres a good chance it is defective. Techs on this forum have found the vast majority of carbs sold on FleaBay and Altozon are not worth the money people think they are saying. We’ve even seen the wrong carb packaged under different OEM numbers.