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Hello again everyone!!

I recently acquired an older Bolens Chipper/Shredder with a 5hp Tecumseh engine on it. I had used it last year and after a quick tune-up and replacement of the wire to the "run/stop" switch that a mouse had chewed through it ran like a champ. It doesn't like to run super hot and after a while the engine will shut off and will only run again after it has cooled. After borrowing it this again this year he says just keep it!! NICE!! I'm pumped because its a great little machine for what its used for.

Last week after getting it back I throw some fresh gas in it and after 2 pulls it fires right up! I use it for maybe 20 mins before it shuts down (which is normal). I organize my branches and what-not for a while to give it time to cool and give it a few pulls to no avail. I let it sit until the next day when I take a look at the carb to give it a quick cleaning to make sure its not clogged. Still nothing...

Here's what I know and did so far:

Changed spark plug.
Checked to make sure the plug is sparking by unscrewing the plug and grounding it against the frame to see the spark.
Cleaned jets in carb and "reset" both screws to "factory" settings as maybe they have a tendency to vibrate out. (which in hindsight maybe was a mistake)
Checked wire to "run/stop" switch for resistance and checked the switch itself. (which i think it did right)
Removed air filter (not clogged) and sprayed starter fluid into carb and still wouldn't start.

The engine cranks no problem but doesn't show any sign that it wants to start at all. Could something that im not thinking of have vibrated loose? Since I'm sure it's getting gas to the carb and the starter fluid didn't work does this mean it's a electrical/spark issue?

Any ideas or help would be greatly appreciated.

The word -- mouse -- is the clue . Those air cooled engines usually have a metal shroud that directs cooling air across the head . A favorite in many to build a nest out of the rain . With engine running you should be able to feel a strong air flow with your hand across the head / spark plug area .

EDIT: the above was for the over heating problem only . For the no start problem disconnect the kill wire you repaired then check for spark at the plug .

you can have spark outside the engine and none when there is compression. Get a spark tester
Check the compression
Check the grounding wire again.
Check the fuel again, and check the oil to be sure no fuel in it.
Try it with starting fluid again.
Clean out the mouse nest because that may be why it is over heating

Hold the spark plug wire approx 1/4 inch from ground and check for spark. Usually easier with the spark plug removed. If it will spark across a 1/4 inch gap the ignition is not the problem. If it won't then replace the coil.

Pull the blower housing off and check the timing key
It should make a perfect square
With unused motors I start by shooting a VERY SHORT shot of carb cleaner down the spark plug hole
If the engine fires normally then the spark timing is good
If ou get a flame out the carb then the intake valve is stuck open
If you get one from the exhaust then that could be OK or could be exhaust valve stuck open .

Did the simple tests Hammer and bert suggested and received the following results:

Could not get a spark unless in direct contact with the grounded surface.
Sprayed a shot of carb cleaner directly into the spark plug hole to no avail. (no change, no flame, no backfire nothing)

Seems like spark is def the issue in some compacity.

Does anyone know what the resistance on this particular coil should be? Just figured id give it a check before I replace.
Thanks

may not help even if it measures right, the secondary may be jumping a small gap between wires internally and not actually shorted as you think of it. Was the air gap clean and correct? I have heard of filings getting picked up over time and shorting the air gap out as to proper magnetism.

Post the engine numbers so we know which coil you have.

Rivets said:

Post the engine numbers so we know which coil you have.

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The sticker is pretty worn down but it looks like H50 65597V (B) 3265D. Not familiar with Tecumseh products and its missing most of its stickers and tags so hopefully this is what we need.

sgkent said:

may not help even if it measures right, the secondary may be jumping a small gap between wires internally and not actually shorted as you think of it. Was the air gap clean and correct? I have heard of filings getting picked up over time and shorting the air gap out as to proper magnetism.

Click to expand...

Good point. The magnet looks pretty rusty and could use a good brushing. As for the gap, i'm not sure what the proper size is supposed to be. My Pepere taught me just to use a piece of paper folded in half... its worked on every B and S engine i've worked on so far!! ?

I think it is .010" I use a special brass sheet but some folks just use a business card.

RustyDGT6000 said:

Good point. The magnet looks pretty rusty and could use a good brushing. As for the gap, i'm not sure what the proper size is supposed to be. My Pepere taught me just to use a piece of paper folded in half... its worked on every B and S engine i've worked on so far!! ?

Click to expand...

Leave the magnet alone
The rust makes no difference unless it is thick enough to touch the coil as it passes.
Wire brushing magnets is not good for them
If it was a problem they would be painted at the factory .

Your unit has a solid state ignited, so there is no way to accurately measure resistance. This manual may be of some help. https://www.mymowerparts.com/pdf/Te...P-4-CYCLE-L-HEAD-FLAT-HEAD-ENGINES-692509.pdf

Sorry for the late update. Amazon delivery took a while and I've been busy but I threw the new coil on yesterday and it fired up no problem!!!

Thanks for all of your help everyone and see you next time!!

super that it worked out. Figure out how many hours/years etc are on the unit and what the odds are you will keep it that same length of time. If that sounds reasonable buy a spare coil while you can. Example - if it is 5 years old and you think you will have it in 5 more years get a spare coil. If it is 18 years old and you don't see it with you in 18 more years then don't worry about it.