Tecumseh ground/spark issue.

[PAPSTISY]

No spark when holding plug wire and testing. But have major spark when I use myself as a ground between wire and metal on motor. Checked, cleaned and positioned correctly ground wire against block and magneto. Coil and condenser left. What do you think it is?

 

[metal man]

So if you put the wire to the block no spark jumps the gap but if ya put a finger in the way ya got spark ? Is your plug wire cracked and shorting to the block ? Thats what it sounds like

 

[Docdc]

I see this a lot in chain saw type motors. It usually turns out to be a weak coil. I would possibly look there. Of course it could be a condenser, bad wire, etc:etc. Just a thought.

Doc

 

[PAPSTISY]

So if you put the wire to the block no spark jumps the gap but if ya put a finger in the way ya got spark ? Is your plug wire cracked and shorting to the block ? Thats what it sounds like

You are correct. That is what I meant to say.. JK

The plug wire is actually really well. The ground wire with prongs are also good. Ground wire attached to magneto case good and engine block good.

Coil or condenser? If either wouldn't the spark I do get when using finger between gap be weak? I will tell you it's like new when you do get zapped.

Any other ideas? Otherwise I will just need to replace C&C. But I'm not convinced those are the problem either.

 

[metal man]

You can get a spark with no condenser and a nice big fat one at that , just ask i know . Do you have a ohms tester ? Do a measure across the plug wire to ground tab and the points wire. to ground tab . Lookin for a bad coil . Maybe post a pic of it ?

 

[Havasu Dave]

Hi Paps, good to see you still messing with these things. An ohm meter will not tell you anything either. Since it is working intermittently without the plug gap, it will read something other than infinity. Metal man is right, they will fire without the capacitor. It's job is to prevent coil feedback across the points. I highly recommend getting a spark tester. I use this one from Oregon and it's about $8. From your description, I'd "guess" magneto breaking down.

The tester makes the spark have to gap, which requires more voltage than shorting it to your body parts, and you can set that tester up to make it fire under compression.

https://www.amazon.com/dp/B0086O8Q8...52&hvtargid=aud-416395350856:pla-310347789777

 

[PAPSTISY]

Thanks Havasu! When I pull certain bikes out of deep storage for son, i usually get the bug to start tinkering again. Or when I score a bike. However, that seems to be impossible these days.

 

[metal man]

Well ya its kinda ues less to ohm it but sometimes it will show a bad wire or other . Take the plug end off the terminal and look at the wire may be skin the wire back a1/2 inch it could be a bad connection there had on do that to me every thing looked good but little crap under the crimping got me

 

[PAPSTISY]

Problem solved. Backwards placed cam lobe. What star? LOL Great example why you don't put motors back together when running on little sleep. I even set the points like that. That's just embarrassing. Not sure how that being placed wrong messed with ground. I do know when its placed wrong the lob doesn't slide all the way down shaft. Which causing all kinds of miss aligns. Regardless, it sparks.

 

[Dr. Shop Teacher]

I'm surprised you even got the cam on backwards...those things don't like to on in reverse. But glad you got it going!:thumbsup: