OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines briggs quantum xm50 wont run?

hi guys,

i have been trying to get this mower running it was brought to me with a broken throttle cable.

i fixed the throttle cable
when i tried to start it it would just run for a few seconds then stall the revs wouldnt pick up at all
so i pulled the carby off and cleaned everything and blew compressed air everywhere (including the main jet)
got rid of old BLACK fuel that was in the tank
replaced the air filter
replaced the gasket between carby and air filter/primer plate
replaced a perished fuel hose
checked the flywheel key but its fine
cleaned spark plug it had some oil by the look of it
so now im thinking the rings might be gone although it seems to have plenty of compression using my thumb on the plug hole (i have no compression tester) what is the easiest way to check the rings?

or any other ideas please

the engine numbers are: 12f802-1911-b10205 1758

cheers, Emmo

Here is the Illustrated Parts List:
http://bsintek.basco.com/BriggsDocumentDisplay/18hruJXHnfBhU7y.pdf

Here is the Operator's Manual:
http://bsintek.basco.com/BriggsDocumentDisplay/29lpAFKT9FzXFix2.pdf

The engine was made on 17 May, 2002.

The Operator's manual has instructions for starting the engine. We need to see pictures of it. At this point I do not know whether its carburetor has a manual choke, and automatic choke, or a primer. We also need to know what you did between when it started running, and when it stopped running. Did you open the choke, or move the speed control?

If you can feel substantial compression by putting your thumb over the spark plug hole, it is unlikely that lack of compression is keeping it from running, especially after it started easily.

ok sorry i cant get any photos at the moment

it has no choke
it has a primer
and will only run for a few seconds
i dont move anything while trying to start it

i hope this helps

i can now get it to run if i put pressure on the spring that connects to the carby butterfly but it stalls as soon as i let go

how do i adjust the spring so it holds the butterfly open so this will run?

so you have had the tank off ? make sure the bellcrank is on the right side of lug on inlet tube / manifold or it will run flat out or not at all . try for a good picture of the carb and linkages , east to tell then might be adjustment as they do still have a little

well i finally got it to run
just had to bend where the spring is connected next to the throttle cable
kind of hard to explain without photos but camera is on holiday with friends that dont have one.

cheers, Daniel

Sounds as if you adjusted the governor speed setting, and Dave's diagnosis was correct.