Heymow - Lawnmower Racing Forum

Engine Help => Briggs Flathead => Topic started by: CedarHill on April 05, 2020, 06:31:49 pm

Title: 19.5 hp opposed Briggs
Post by: CedarHill on April 05, 2020, 06:31:49 pm
I have a 19.5 hp opposed Briggs on an craftsman about 20 years old. The engine starts and runs good but after about 30 seconds it will shut off and it looks like a small amount of fuel comes out the top of the carb. The problem doesn’t occur with the choke shut about 3/4 of the way. The carb has been cleaned and I even tried a replacement I had lying around. Just wanted to know if this was normal or if there is a way to run it with open choke.
Title: Re: 19.5 hp opposed Briggs
Post by: birdman_express on April 05, 2020, 06:45:21 pm
If you  did not use a new kit when you cleaned it, there could be leaks from the needle or other gaskets,
or a combination of both.
Title: Re: 19.5 hp opposed Briggs
Post by: CedarHill on April 05, 2020, 06:56:41 pm
We had a good gasket that we put in, but I haven’t checked if the needle is seating.
Title: Re: 19.5 hp opposed Briggs
Post by: CedarHill on April 05, 2020, 07:00:40 pm
We have another mower that’s exactly the same and it never had this problem. I wonder if it doesn’t get good spark and wont burn without choke?
Title: Re: 19.5 hp opposed Briggs
Post by: birdman_express on April 05, 2020, 07:21:07 pm
Carb is dirty if you have to run choke.
Title: Re: 19.5 hp opposed Briggs
Post by: CedarHill on April 05, 2020, 07:47:33 pm
Ill go through everything again and see what happens. Dirty carb is the only thing that makes sense but its weird how it runs for 30 seconds the shuts off like you turned the key.