Problem with spark plug wire

[spazoo]

I was riding yesterday and the engine quit and would not restart. After I pushed the bike home I noticed the wire connecting to the spark plug was missing. I found it dangling from the coil. Somehow this wire broke while I was riding.

According to the parts list for the scooter the coil and wire are a single part. Does anyone know where I can order this?

Thanks.

[scooterollie]

Spazoo;
The MC-54B is a new product this year. How long have you had it? Still under warranty? Have you tried your dealer or anywhere else?

[spazoo]

Thanks for the reply.

It is still under warranty. I have talked to my dealer and he is going to try and get me the part. If I can find it elsewhere I will have a spare.

I took the "boot" off of the spark plug because the wire separated from the boot. I was looking inside to see where the wire broke. I did not see any copper strands of wire. The only thing I saw was the pointed tip of a screw. So I put the boot back on the plug and I pushed the wire back into the boot. I was then able to start the scooter again.

Is it possible that this wire just vibrated loose and the only thing that keeps the wire in contact with the tip of the screw the boot itself?

[monty57]

spazoo,

Yes it is entirely possible for the wire to fall out of the boot. But let's backtrack a bit.

First, most spark plugs wires are not actually wire. The are called "resistance" spark plug wires and are actually made of carbon impregnated fiber. This reduce RF generation or "ignition noise" some times heard on a near by radio and they work better with todays high output ignition systems. The boot has the screw so it can be twisted into this carbon fiber and make the connection.

So, to make a more permanent fix, remove the boot one more time and twist it clockwise (while looking at the end of the wire) a couple of turns to make sure the screw is into the fiber as far as possible. This should fix you problem.

[spazoo]

What about the stranded copper wire that is sticking out of the end of the cable? Does it need to touch the screw? My spark plug wire has about a half-inch of stranded copper wire sticking out of the end that goes into the boot. I was assuming that wire had to make contact with the screw.

Thanks for the help.

[monty57]

Ok, I am little confused as in your first post you say you did not see any copper wire. If you in fact have a solid or stranded copper spark plug wire. Cut the the strands even with the end of the insulation and then push the wire back into the boot so that the screw goes into the center where the wire is located and then twist it on.

[scooterollie]

Might even be a good idea to use a cement on the end of the wire that goes into the boot. That will seal it from moisture and perhaps prevent the same thing from happening again.

[spazoo]

Sorry I did not explain very well. What I meant to say was that I did not see any copper wire inside the boot. I only saw the tip of the screw inside the boot. And by tip I mean 1/8 inch. Not very much of the screw is showing.

The wire that goes into the boot has about 1/2 inch of stranded copper wire that extends out of the insulation.

Currently the wire is pushed into the boot with the stranded wire most likely making contact with the tip of the screw. So I should remove the wire, trim the stranded wire back, even with the insulation, and then cement the wire into the boot?

Thanks again for the help.

[scooterollie]

Spazoo;
Yes, that is the usual way, end of wire flush with insulation. Coat the wire and inside of the boot with cement, screw on the boot and let it sit to cure.

I think most scoots will have the stranded wire conductor (like yours), not the carbon fiber type.

[earlwb]

You need to screw the wire into the boot so it screws onto the little screw on the inside.
The resistance wires use a flexible carbon conductor on the inside, so there isn't any copper wire in resistance wires. Resistance wires reduce radio interference so people can listen to their radios without engine noise causing sound quality issues.

[spazoo]

Thanks for the help. i will give this a try.