Install new spark plug leads

[Red Barron]

How do I install new spark plug leads on my 1988 GSX1100F?

My number 4 spark plugs gums up and the engine has some vibration. If I decide to replace the lead how do I do this without replacing the cols as well? I would need to replace the connectors and the rubber boots as well as the cable.

[kevin2502000]

I am going to do this to mine in a few weeks, they are allergic to water and only run on 2 cylinders. It's CP's post.......


#11 The CyberPoet
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The kats, by design, have no issue with the rain (and I've run hundreds of miles at a pop through some torrential storms regularly).

I would suggest what I suggest to every rider with a new bike (or new-used), and that is strip the fairings, pick a starting place, and working around the bike in one direction, disassemble each molex connector, spray it out with electrical cleaner, then after that evaporates, slather it full of dielectric grease and reassemble, move on to the next connector. Go around the bike a second time to spot any you might have missed. Be sure you hit the coil's connectors, the spark plug boots, the CDI, the battery terminals, the fuse-box spades (gotta pull the fuses to get them), the relay receiver next to the fusebox, the many-pinned connectors above the headlights on the 98+, all the connectors to the left side of the battery outside the frame, etc.

BUT, I suspect in your case it might actually be the spark plug wires have seen better days, simply because of the age of the bike. If this is the case, you have a few options:

(A) Order replacement coils -- these will come with the spark plug wires pre-attached from the factory. Pricey, but absolute peace of mind. I tend to go "replace-with-new" mentality myself many times because I am often very, very far from home when I'm on the bike and want the rock-solid assurance of reliability to be absolute.

(B) Replace just the spark plug wires themselves. This is quite a PIA, because they are permanently mounted to the coils. You have two choices here - either carefully disassemble them from the coils and epoxy the new ones into place (search for a write-up here on KR), OR cut them about 1/2" from the coils and use an NGK Spark Plug Wire splice to connect new ones. The Spark Plug Splicers (physical connector) run about $8 each last time I looked...

(C) Reseal the existing plug wires with new insulation against both water and electrical. How do you do this? Well, I'd do it specifically this way:
1. Get 20 feet of 2:1 heat shrink tubing in the right post-shrink size for the spark plug wires, as well as about 35-80 feet of silicone tape (I tend to use Rescue brand tape - www.rescuetape.com); how much silicone tape you'll need relates directly to the width of the tape (4 times the length of all the wires is basically your need) and the thickness. You could use just one of the two solutions (or double-up on either, such as double heat-shrink), but both together works best. Get some dielectric grease as well. Note that RescueTape can usually be had at cheaper prices than their website shows via other sources...
2. Spray the wires with electrical cleaner or wipe them down with 91% rubbing-alcohol (you want to drive off any water in the exterior without leaving behind any oils to deteriorate the existing material).
3. Remove the boots & plug holders off the end of the wires. Good time to check the wire condition and check to see if you can afford to cut off a 1/4" of length later.
4. Slather a bit of dielectric grease around the base of the existing plug wire where it meets the coil, covering about 1/4" of the junction.
5. Slide the heat-shrink tubing over the spark plug wire all the way down to the coil, cut to length so that you have about 1/4" excess on the spark plug end. Heat the tubing with an appropriate heater (hair dryer OK, but don't use lighters/torches, best to use an industrial heat blower if you've got one), working from the coil end forward towards the plug end and rotating to hit both sides of the tube.
6. Once shrinked the full length, trim the end at the spark plug boot back by 1/8 - 1/4" including the wire, to expose clean, healthy wire for the boot to bite into when you reassemble.
7. Now wrap the heat-shrink with the silicone tape as per it's directions (i.e. - wrap under tension so the silicone tape is "stretched" a bit -- this activates the hold and accelerates the melding process). Your wrap needs to be approximately 4 layers thick (based on a voltage value of 30k volts max and a voltage resistance rating of 8k volts per layer for rescue tape). Obviously wider tape will make this part of the process easier. Be sure NOT to wrap the last segment of the wire that the boot needs to fit over.
8. Inspect the spark plug connector, clean/replace as necessary, then slather with dielectric grease and reassemble with the boot onto the wire.

Repeat for the other three wires.

Cheers,
=-= The CyberPoet

[Red Barron]

Thanks Kevin. That's a very comprehensive piece of information.

Out of interest, can anyone offer an opinion: I had problems with the ignition a few days back. I had to dismantle the switch and clean off a heap of junk. As yet I haven't applied any contact lubricant (because I don't have any and work pressures have kept me away from a shop). Is it possible that poor conductivity in the ignition switch could push the high-tension current below some threshold and cause problems with a spark plug? I was thinking that if the spark plug lead was a little dodgy then a small amount of loss might have a significant effect.

Is this possible/feasible or am I dreaming?

[KYOTE1]

How do I install new spark plug leads on my 1988 GSX1100F?

My number 4 spark plugs gums up and the engine has some vibration. If I decide to replace the lead how do I do this without replacing the cols as well? I would need to replace the connectors and the rubber boots as well as the cable.

to avoid alot of money dismante the coil and wires from the bike, and again dismantle the plugs off each wire and snip off the hardened wire insulation on each end of the wire and reassemble. the wire ends screw in. over time the wire hardened due to the high voltgaes that pass thru them, the insulation breaks down and you get electrical "leakage". this will produce a poor spark.

if this solves your problem get new wires or just ride. If not, you know you have eliminated this as the problem and you can move on to the next area.

this worked for me. my leads fell apart when i yanked on the ends. good luck

[Red Barron]

Great idea, Kyote. I think that's what I'll try.

[Red Barron]

Where can I buy spark plug lead? I've checked out a couple of auto parts places and they only stock leads that are made up for specific vehicles. A guy told me today that you can't buy it any more because leads are now carbon core and they have to be pre-assembled.

Any suggestions about where to get some? Ideally it would be in Brisbane or Queensland or Australia.

[KYOTE1]

do you snip the wires yet

[Red Barron]

My first task for this morning, it being Saturday now in Brisbane, will be to snip the leads. I was being cautious, trying to locate parts I might need in case I need to run out and buy stuff during my weekend of motorcycle maintenance.

[DClark]

The caps are $25 from the dealer. You can similar but not the same caps from DK for less.
I have 7mm wires connected to Dynacoils.
The stock wires have a strange plastic like insulation that can get brittle when old- brittle=electrical arcing.

[Red Barron]

Well, I snipped the wires. It was not easy screwing the cap into the lead and I'm not convinced it is screwed all the way in. Is there some special technique I should use? Still, it is working. I installed a new set of plugs while I was at it. So far so good.

[KYOTE1]

Well, I snipped the wires. It was not easy screwing the cap into the lead and I'm not convinced it is screwed all the way in. Is there some special technique I should use? Still, it is working. I installed a new set of plugs while I was at it. So far so good.

just screw it in ensuring it goes in as far as the it did before eye ball measurement