OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Briggs 8HP. missing/hunting

Hi Guys

I've have a briggs 8hp on a rover colt that I bought a few weeks ago.

I've replaced the coil, carby and given it a freshen up but I can't get it to run smoothly. It almost runs as though it starves for fuel intermittently. I've had the same issue with both the new and old carby. I've gotten it to slightly improve with giving it a tune but it does continue. Some of the head bolts weren't all that tight which I only noticed the other day but I'm not sure if that would have any bearing on it.

It does seem like after 5 or 10 minutes of mowing it seems to gradually get smoother. The governed appears to hold steady it just sounds almost like I'm sticking my hand over the air intake about every 5 or 10 seconds.

Cheers

Hi gizmo1993

https://www.lawnmowerfixed.com/mower-engine-surging/

The most common reasons for a surging
Bad Fuel
Bad spark plug
Dirty / faulty carburetor
Fuel filter blocked
Fuel tank blocked
Fuel line blocked
Gasket vacuum leak
Manifold vacuum leak
Governor control fault


You can apply a half choke with the engine running if you have a motor without a choke holding a finger half over
the carby intake will do once the air filter is removed.

If the engine now runs without surging – Gas starvation is the likely fault. If it runs just the same .A vacuum leak is the more likely fault.


Cheers
Max.