Ignition Coil Leads

[Sparky84]

Can anyone tell me if the Spark Plug Leads can be removed and reterminated onto the Ignition Coils?
I have intermittent fault on Lead 4, I have installed new Cap and in the process cut back Lead and reterminated onto Cap.
Only 1 other spot to reterminate is at the Coil But I don't know if the Lead will come out or whether I'll stuff it up.

Cheers
Alan

[movenon]

Yes. on my 1990 I replaced all the wires.  From memory, you can twist out the wire from the coils.  I believe the wire is 7mm SOLID core. The caps are resistive.
Purchased the wire from NAPA but any auto parts store should stock it.  From my notes I removed the coils to take the wires out, the wires going into the coils are bonded a bit, just work them loose. I bought 5 feet of wire and did all 4 of them.  Camfor the wire edge a bit that fit back into the coils and lube them a little with some die electric to help slide them back into the coils.  That's with stock Yamaha coils. Aftermarket coils might take a larger diameter of wire.
George

[Earl Svorks]

   George is spot on with his advise on the coil wires. I would add only the following: The leads go deeper into the coils than you might guess., like nearly 2". It has proven difficult for me to get the wire out cleanly and completely in the 3 or4 times I have done this . There is a tool that has been very helpful . This being a seal puller that looks like a corkscrew on the end of a flexible drive (like s short fat speedo cable) with a little "T" handle on the other end. Any old corkscrew won't do because it will be too large in diameter to go inside the 7mm bore. The long spike needle in the bottom of the bore prevents the use of a drill or reamer to scrape the remains out. The puller I mention is available to anyone who knows where to buy industrial hydraulic seals, chevron packings and such.
The only other option I have seen are butt connectors made for plug wires. NGK used to offer them.
they are well sealed with packing gland nuts at either end. I have used them successfully a couple of times where coil wires could not be removed.
    Cheers
   Simon

[Sparky84]

Thanks George good to know that they can be replaced,
but if Simon is right and they are that hard to get out maybe the end in the coil is OK...

I think I'll get some 7mm solid core cable and give it a go anyway

Cheers
Alan

[Pat Conlon]

The FJ's oem steel core wire is very durable. I would be surprised if the wire leads were a problem.

The resistor plug boots are another matter.

[Earl Svorks]

  Alan,
How are you able to be certain your intermittent condition is exclusive to lead #4? The other end of that secondary winding is lead #1. How are you connecting your VOM?
   Simon

[Pat Conlon]

Move the #4 lead onto #1 cylinder (and #1 to #4) ...see if the problem moves over to the #1 cylinder.

[Sparky84]

  Alan,
How are you able to be certain your intermittent condition is exclusive to lead #4? The other end of that secondary winding is lead #1. How are you connecting your VOM?
   Simon

Gidday Simon, I had a dyno done awhile ago and the dyno tech had trouble picking up revs utilising lead 4, it would be ok at idle but higher revs stop/start
but had no trouble with lead 1 and as you have said 1&4 are from the same coil.

So I'm putting it down to a connection on #4, the problem is which One, if I do All I'll probably get the right One

Cheers
Alan

[Earl Svorks]

    I agree with Pat regarding the resistor caps. They are a common source of such trouble. You can easily check them,off the lead they should read around 5K ohms. As far as the dyno test you spoke of,
I have found that an inductive pickup can fail to read ,or 'see' a spark for reasons you wouldn't suspect immediately. Anything that prevents the voltage rising enough to create a good spark, like a fouled/shorted spark plug, a mixture too rich or oiled that won't fire. Even low primary voltage can cause this. The caps themselves were made in such a way that the brass fitting that clips onto the threaded bit on the plug end, had a big slot for a standard screwdriver that allowed the fitting to be removed. Under the fitting you will find the actual 5K resistor and a little coil spring to hold the assembly tight. The resistor can be measured out of the cap. If it's faulty you can eliminate it with a longer spring. Your radio may buzz a bit but that is about the worst thing to happen. Be aware that the NGK plug caps are/were available in 5K and 10K values. Suzuki often called for the 10K type. I have seen the math on the actual voltage difference in secondary output between the two. Surprisingly , it's very little and not worth worrying about.
    Cheers
   Simon