No Ignition

[shelby1]

OK yes I know this is not a go kart...... I have worked on small engines all my life ( I am 74) built kart race engines mini bikes etc. now I have come across a problem that has me stumped , have a small push mower , that has a Briggs motor on it , wife tried to stat it at start of our mower season ( we are in South Alabama ) wont start, so I think ethanol gas sit over winter got carb clogged cleaned nope still wont start ....so pulled plug spin over no fire......short story I have changed to new plug, ignition coil cleaned magnets on fly wheel even tho I have never seen surface rust prevent a mag coil from firing....nothing no fire .....so I have changed every thing in the ignition system , tried starting with kill switch disconnected ....nothing ...has to be the simplest ignition system there is ......??????? any guesses
Kenny

 

[Flyinhillbilly]

That’s odd, I would think it should start too.
I like to think that I have a pretty good grasp of these little engines, but sometimes they show me that I don’t.

 

[itsid]

have you checked the spark plug boot and wire?
or did you changed that with the coil (as most do)

IDK it's indeed odd ...

'sid

 

[shelby1]

Yes .....thats what I do not understand .....I have changed everything and still no spark.... I have been a mechanic for most of my life and have ran across some weird things but always figured them out....but this one has me stumped and i don't take that lightly .....case in point showed my son what was going on ..... his reaction .... Are you serious Dad YOU can't figure out what is wrong with it?....He said...I have never see something that you could not figure out whats wrong.....made me feel bad coming from my own son

 

[Joe-405]

How exactly did you check for spark ? And got a pic or two by chance ? I was a mechanic for a small engine shop for a while here in Oklahoma.

 

[JTSpeedDemon]

Magnetron systems have fainter spark sometimes. Check it in the shade.

Is it a pointsless Magnetron system? Or is it the old school points system?

Here's some things to check:
Have you replaced the ignition points and condenser under the flywheel?
Can a screwdriver hang upside down off the flywheel magnet?
Are the mounting posts for the coil corroded?

Something's not right.....

 

[shelby1]

yes checked it in the dark.....nothing

---------- Post added at 05:38 PM ---------- Previous post was at 05:32 PM ----------

I guess it is a Magnetron system ....full electronic .....son just called me and said he talked to a buddy and he had one do the same and it was magnet in flywheel went bad ,,,,I have personally never seen a magnet go bad ....not saying that its not possible.....screwdriver hangs good on magnets.....I am totally stumped......
Kenny

 

[JTSpeedDemon]

You sure it's a Magnetron? pop off the flywheel just to make sure.

 

[Budget GoKart]

Grab the spark plug and have someone pull the string really hard if you feel nothing then i have no clue

 

[Karts of Kaos]

are you sure you got the right could and the coil is not meant for a points system?

 

[Brianator]

Or if it does indeed have points and condenser are the points pitted/corroded? You can use a multimeter to test them for continuity. Every small engine I've seen (so far) with points has an inspection cover on the flywheel

---------- Post added at 11:29 PM ---------- Previous post was at 11:20 PM ----------

Grab the spark plug and have someone pull the string really hard if you feel nothing then i have no clue

In case you weren't aware.... that could (and probably would) kill somebody with a pacemaker. Food for thought.

 

[Karts of Kaos]

you Know I am glad I don't have a pace maker. i have been shocked many times by spark plugs.

 

[shelby1]

OK I know this has nothing to do with this thread...... grabbing the plug wire to check if it has fire brought back some old memories from when I was in my pre teens.....my brother was working on a old flat head jeep had a bunch of friends and their girl friends out there ,my brother was showing off and said he could kill the motor by grabbing the spark plugs....now remember these motors had no spark plug boots which he proceeded to do ....I saw him do this twice ....I knew he was showing off because the girls were there ...... sooooo I had to do it ..... I said that is pretty cool lets see you kill this lawn mower like that well with out thinking he grabbed the spark plug and it lite him up.......it is a magneto and it will produce fire as long as the flywheel is turning which it will cause it is still firing the plug ....it embarrassed the fool out of him.....he never let me forget that little incident.....
sorry for the rant .....so miss my brother...