B&S Quantum 6.0 122h02-0220-b1 Drops out and dies

[zap_rowsdower]

I have a Craftsman 22" weed trimmer with a Briggs & Stratton Quantum 6.0 122h02-0220-b1 engine. It starts and runs fine for 6 - 8 minutes then it just drops out and dies and can't be restarted for hours. To top this issue off, I can see thin whisps of smoke coming from the muffler and debris screen on top of the mower. Unit is clean and free of debris, oil is clean and showing the appropriate full measure on the dipstick. Spark plug is new. Air filter is not new but is clean and free of debris. Gasoline is fresh.

If I try and re-pull start the engine it is free and shows plenty of signs of life but does not want to start. I have what I think is an overheating issue, but I'm not sure where to go from here. Any first steps for consideration?

 

[mechanic mark]

engine definitely needs cleaning with shop vac, remove blower housing, top cover of engine, & clean cooling fins on engine with shop vac, engine has to breathe. check engine coil for replacement.

https://www.google.com/search?q=how...ome..69i57.46028j0j4&sourceid=chrome&ie=UTF-8

 

[MowLife]

Do what is said above to keep the motor as cool as possible. When the motor dies and won’t restart immediately check for spark. The coil is a good possibility at fault. They are known to stop working when too hot and after it cools start working again.

 

[Rivets]

Next time it happens try removing the gas cap for 30 seconds and then try restarting. If it restarts bad gas cap.

 

[Scrubcadet10]

get ya one of these, makes checking for spark easier... i guess enough sense got shocked into me and i finally bought one :laughing:
https://www.amazon.com/Oregon-42-087-Line-Spark-Tester/dp/B0086O8Q8K

 

[zap_rowsdower]

Gave the engine a deep cleaning, unit fired right up, and... died again at around the 8 minute mark. However, there's no longer any whisps of smoke. That engine was dirty. I have a replacement ignition coil on the way.

While I had everything apart, I took the liberty to give the housings a little paint to brighten up the look. Not that it matters, but it looks a little better than what I started with.

 

[Scrubcadet10]

Looks good!
verywell could be a ignition coil cutting out after it heats up.

 

[zap_rowsdower]

All right! Back after a few days and am happy to report that a new ignition coil (and an deep engine cleaning) has solved the problem with this weed trimmer. The part number for this ignition coil is 590455 and is described as both an ignition coil and as an armature magneto on various shopping sites. Photo of the old ignition coil is attached so you can get a look at the old part.

 

[bertsmobile1]

get ya one of these, makes checking for spark easier... i guess enough sense got shocked into me and i finally bought one :laughing:
https://www.amazon.com/Oregon-42-087-Line-Spark-Tester/dp/B0086O8Q8K

You will find one of these a lot better because the globe glows orange thus you can see it easily in sunlight.
https://www.amazon.com/Oregon-42-031-Small-Engine-Tester/dp/B0000AXCOV/ref=sr_1_4?keywords=oregon+in+line+spark+tester&qid=1564452151&s=gateway&sr=8-4
Most mower shops & some car parts stores carry them.
While the 3 point tester is good for verifing that the coil is putting out a spark at full strength, ignition systems are now not servicable so no orange flash with the kill wire disconnected = new coil
Trying to see a blue-white spark from 4 foot away on a shanking engine while you are pulling a starter cord is a tall order.
If the globe flashes with the plug in the engine there is enough energy to throw a spark.
If it does not flash there is not enough energy to throw a spark.
I have verified this by connecting it directly to the block on an engine that showed no flash and it would flash when shorted to the block but not when connected to the eplug
Tried the 3 point tested and sure enough, throws to the close points & not the distant ones
Finally triple checked , cause we like to play with things with a sliding contact tester and the spark failed at 1/8" gap.