Toro Brigss & stratton "ready start system" ain't startin'

[turnipgreens]

Briggs & Stratton 128M02-0133-F1 DOM Apr 2013
190 cc 7.25 on a 22" walk behind mower

Howdy, I need some help please.
I have a Toro Brigss & stratton that I bought new, have always ran non ethanol fuel, has dependably started and ran for years until now. If I spray some carb cleaner in the it will try to start/run for about 2 seconds and stops. I do spray it off with water after each use, always have tilted it carb side up.

Checked carb fuel bowl (clean, no water) and contained fuel , float moves, and jet was clear but ran wire through to confirm,
Auto choke assembly and springs are in place,
Replaced the dirty spark plug with same new Champion RJ19LM,
replaced dirty air filter (it wasn't fuel or oil soaked),
replaced Ignition coil with new B&S,
flywheel key is intact,

All that and still the same issue.
Does this machine have a hidden fuel filter or something, starving the fuel intake?

Thanks!

 

[bertsmobile1]

No but it has valves that need to open & close to allow the fuel in and the exhaust out.
It has a long manifold that runs across the entire engine that is prone to cracking or coming loose.

 

[turnipgreens]

No but it has valves that need to open & close to allow the fuel in and the exhaust out.
It has a long manifold that runs across the entire engine that is prone to cracking or coming loose.

Thanks, but on this unit it appears the muffler directly attaches to the motor. On disassembly, I did not notice a manifold.
My motor appears the same as the one in this video.

https://www.youtube.com/watch?v=ThaFhoDw75U

There was oil dripping from the motors exhaust port and muffler.

 

[Scrubcadet10]

The manifold is the intake manifold. If you look at your mower you will see it goes to the carburetor. Any cracks in it, or around where it mounts and it will have a hard time pulling fuel in.

 

[turnipgreens]

The manifold is the intake manifold. If you look at your mower you will see it goes to the carburetor. Any cracks in it, or around where it mounts and it will have a hard time pulling fuel in.

Thank you, bertsmobile1 & Scrubcadet10.
After disassembly (it was snug 'goodntight') and cleaning it off the Intake Manifold appears structurally sound.
It looks just like this new part (Briggs & Stratton 796703)

 

[bertsmobile1]

OK ,
Scratch one off the list but only if you have checked the underside of the manifold.
Either saturate it with WD 40 or similar , spin the engine then check for WD40 on the spark plug
OR pull it off turn it over and do a visual check they have been know to split the entire length underneath.

If it tests sound ( don't over tighten the tiny bolts ) remove the kill wire from the coil then attempt to start the mower again.
If it starts & runs ( note you will have to pull the plug lead off to stop it ) then your problem is the kill switch.

If there is no difference they you have crossed 2 items off the check list.

Next is to pull the carb off, turn it sideways and blow air through it from the filter side.
If no fuel comes out then the carb is blocked
If fuel blows out then that leaves you with timing & valves.

Timing is easier to check than valves so pull the blower housing off , remove the bolt / nut and the starting cup.
Under there you should be able to see the 2 timing key slots.
They must line up together to make up a perfect square .
You can do this earlier on while the blower housing is off.

The last thing to check is the valves .
The valve chest resides behind the muffler.
Usually on a side valve the exhaust seat burns away so the exhaust valve does not fully close.

If they barely move then the cam is worn out.

If you have a red flashing spark tester you could hook it up to the mower before you pull it apart and check that it continues to spark even when the engine has stopped firing.
While the flywheel is rotating fast enough and the mower is in the on position you should get a spark.

Some times a coil will fire a few times then break down & not spark.

 

[turnipgreens]

Thank you Bert,
It was a small crack in the intake manifold!

OK ,
Scratch one off the list but only if you have checked the underside of the manifold.
Either saturate it with WD 40 or similar , spin the engine then check for WD40 on the spark plug
OR pull it off turn it over and do a visual check they have been know to split the entire length underneath.

If it tests sound ( don't over tighten the tiny bolts ) remove the kill wire from the coil then attempt to start the mower again.
If it starts & runs ( note you will have to pull the plug lead off to stop it ) then your problem is the kill switch.

If there is no difference they you have crossed 2 items off the check list.

Next is to pull the carb off, turn it sideways and blow air through it from the filter side.
If no fuel comes out then the carb is blocked
If fuel blows out then that leaves you with timing & valves.

Timing is easier to check than valves so pull the blower housing off , remove the bolt / nut and the starting cup.
Under there you should be able to see the 2 timing key slots.
They must line up together to make up a perfect square .
You can do this earlier on while the blower housing is off.

The last thing to check is the valves .
The valve chest resides behind the muffler.
Usually on a side valve the exhaust seat burns away so the exhaust valve does not fully close.

If they barely move then the cam is worn out.

If you have a red flashing spark tester you could hook it up to the mower before you pull it apart and check that it continues to spark even when the engine has stopped firing.
While the flywheel is rotating fast enough and the mower is in the on position you should get a spark.

Some times a coil will fire a few times then break down & not spark.

 

[Scrubcadet10]

Great news! Glad you got it worked out.

 

[turnipgreens]

Thank you to both of you good fellas!

Great news! Glad you got it worked out.