Briggs-Stratton 190cc eng starts fine &runs great for 4-8 min and then appears to flood (backfires) &then very slow idle for 10 sec B/4 stalling Will not restart unless left to set for aprox10 min. ?

On some float-type carburetors, you can adjust the air-fuel mixture and engine speed at idle. Check for an idle speed screw designed to keep the throttle plate from closing completely, and an idle mixture screw that limits the flow of fuel at idle. If your carburetor contains these screws, proceed below.

1. With the engine off, remove the air filter and air cartridge.
2. Locate the idle mixture screw and turn it clockwise until the needle lightly touches the seat. Then, turn the screw counterclockwise 1-1/2 turns.
3. If your carburetor has a main jet adjustment screw at the base of the float bowl, turn the screw clockwise until you feel it just touch the seat inside the emulsion tube. Then, turn the screw counterclockwise 1 to 1-1/2 turns. Replace the air cleaner assembly and start the engine for final carburetor adjustments.
4. Run the engine for five minutes at half throttle to bring it to its operating temperature. Then, turn the idle mixture screw slowly clockwise until the engine begins to slow. Turn the screw in the opposite direction until the engine again begins to slow . Finally, turn the screw back to the midpoint.
5. Using a tachometer to gauge engine speed , set the idle speed screw to bring the engine to 1750 RPM for aluminum-cylinder engine or 1200 RPM for engine with a cast-iron cylinder sleeve.
6. With the engine running at idle , hold the throttle lever against the idle speed screw to bring the engine speed to "true idle." Then, repeat the idle mixture screw adjustments from Step 4 to fine-tune the mixture .

See if by chance there is water in the gas tank. If not, the coil may be the problem after it gets hot.

It sounds like the needle and seat need to be replaced. Somewhat common on Briggs engines.

remove the top cover from the engine and see if there is a nest stopping the governor linkage from moving

sounds like the needle and seat are not sealing

valves bad need valve job

hi there

danielburgi

1 almost sounds like you may have a restriction in the main jet of the carburettor or idle circuit transtional holes or idle air bleed holes , also check emulsion tube

2 then if these are all ok try adjusting governor - as soon as load exceeds power output - unit will try and stall- once governor adjusted re-try -

3 the only other thing it may be is too low compression which ia major concern

try 1 and 2 options 1st


3 is the last option which means a leak test to check compression loss or worn rings



cheers pauly46

hope it helps

Had the same problem with an almost new Craftsman w/ Intek 20.0 HP. Check all the "usual suspects" and had to have a tech come out. He had me start it. It ran for a few minutes and stopped (per usual). He immediately went to the Anti-Backfire solenoid. It is an electrically operated "plunger-style" fuel line blocker. They are famous for going bad. The part is about $65 and its sole purpose is to starve the engine of its fuel supply at shutdown so it won't backfire. If it is disabled, the user must throttle the engine down for 10 seconds or so before turning the key off in order to avoid backfires. Gee... let's see, 10 seconds of my time each time I use the mower vs $65 part ... No contest! Remove the solenoid, take a pair of electrician side cutters and snip off the tip of the plunger and reinstall it. Problem solved ! ! !

with it backfiring i would guess the valves may need adjusting and if that does not help clean the carburator.

(1)You high speed carburetor jet is too lean (2) a dirty carburetor that needs cleaning (3) dirty air filter.