Surging Briggs and Stratton Engine

Vintshave

Member
Joined
May 7, 2020
Threads
5
Messages
15
Hi,

Had an old Briggs and Stratton generator sitting in my shed for a couple of years. Since everything was pretty stale, I emptied and flushed the fuel tank, replaced the corroded fuel valve and replaced the filter and the carburetor. I checked the plug out. Everything was good. I started it and after a couple of minutes, it ran like this:
.

Does anyone have ideas about why it would be surging like this? Basically everything is new.
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,437
Surging is caused by a lean running condition, meaningw, more air is entering the combustion chamber than fuel, OR there is a fuel shortage.
Did you replace the carb gaskets when you put the new one on? Did you replace it with an Briggs carb or a $20 Commucarb from China?
 

Vintshave

Member
Joined
May 7, 2020
Threads
5
Messages
15
Commucarb. Couldn't find the original Briggs carb for sale for this unit.
 

Scrubcadet10

Moderator
Staff member
Joined
Sep 24, 2017
Threads
250
Messages
6,437
Did it come with new gaskets? A ripped gasket will cause a vacuum leak and cause this issue
 

Vintshave

Member
Joined
May 7, 2020
Threads
5
Messages
15
New gaskets. The only other thing is that I had to replace a broken carb spacer with a 3 D printed one since they don't make them anymore. Hopefully I'll be able to find one soon. That could be an issue.
 

Its Me

Active Member
Joined
Apr 11, 2011
Threads
1
Messages
82
you can get the carb. at a mower shop but you can save money with that Chinese crap that don't work, they have not figured out how to make a high speed jet, I seen on the video that you choke it slightly so problem solved, did you try it under a load to see if it will level out, when you done with a generator dump the fuel, take the fuel bowl off and blow the gas off, if not you better get a few more carburetors.
 
Top