Splicing a spark plug wire

[mkirsch]

I've got an old Stihl limbing saw I'm trying to fix. In the process of taking it apart and putting it back together, the spark plug wire broke off just inside the boot.

Looks like the only "right" fix is to replace the entire magneto, but parts are tough to come by.

Now, here's what I did and I'd appreciate it if you could tell me if this is a viable fix:

1. Salvaged a boot and short length of wire off a junked weed wacker engine.
2. Stripped 1/2" of wire on the saw and the salvaged boot.
3. Joined the two wires together and soldered.
4. Split the stripped-off insulation and wrapped the splice.
5. Covered the splice with two layers of heat shrink.

I got nothing to lose on this, and the connection is way more secure than those put-it-together-yourself spark plug wire kits for tractors...

 

[rustyfarmall]

It'll be as good as the original. I probably would have just wrapped the splice with electricians tape and called it good, but the heat shrink wrap is a whole lot better.

 

[Anonymous-0]

Most of those coil wires can be removed. Take your time and with a little twisting and pulling they will usually come out.

 

[shannon from ohio]

Been there,done that. Your splice will be ok with the double layer of shrinktube. I have cut ends off flush and straightened out a staple and poked through each end of wire and then put 2 or 3 layers of shrinktube on my repairs to get me by.....

 

[JT]

As long as you soldered it and then insulated it good, it will work just fine. You are correct, most plug wires cannot be removed, the coil gets replaced.
Jim

 

[Anonymous-0]

I fixed an echo blower the same way after customers dog chewed the plug wire in two. It worked fine. Main thing is to insulate the connection well.

 

[Anonymous-0]

Because there are air gaps in the replaced insulation, it will spit and arc there, burning further holes in that insulation.

It would be better to replace the removed insulation with GC Corona Dope or liquid tape or liquid handle dip.

Gerald J.

 

[Anonymous-0]

Did a repair simular to what you are describing on a 4hp Kohler engine for a roto-tiller once. It worked and held up just like a new part. Far as I know it never was replaced. Might not have been the proper repair, but the folks weren't best off financially so it was a very good fix for them.

Jim

 

[Bob]

NGK and others make splice kits just for such catastrophes.

<img src = "http://www.parkeryamaha.com/ProductImages/lets/j18083.jpg">
Splice

 

[mkirsch]

Thanks guys. I figured it would work but just wanted to double-check before I tried to start the saw and got the shock of my life or something. Not to mention it's not the easiest thing to put together.

BTW, it's not just the heat shrink making insulation. I took a piece of the thick insulation that I stripped off, split it, and wrapped the splice with that before adding the heat shrink.

 

[Anonymous-0]

On the motor mower coil where the plug wire enters there is a screw end inside and the plug wire is screwed in, don't know about chainsaws.I'm speaking of old mowers.