Topic: Splicing into spark plug wires?

[JAG]

Has anyone tried to splice into the spark plugs wires on the bikes to use new wires and caps, without having to replace the whole thing?

My coils are in good shape, but my wires have all sorts of cuts and gashes in them.

This may be a stupid question, but I thought it would be worth a shot. If anyone has tried it, what method did you use to splice the old wires with the new ones?

I don't know how reliable splicing two wires together would be. Don't sound like it could be, but it was just a thought.. 

thanks

JAG

[JAG]

Here's what "sparked"    the interest.
http://cgi.ebay.com/ebaymotors/1975-Cb-750-K-Coils_W0QQitemZ280221224245QQcmdZViewItem

I didn't know it could be that easy, as for my my bike K4, ( and correct me if I'm wrong )  the plug wires are built into the coil...

[neil young]

you can buy NGK connectors at any supplier.i dont have photobuket on this computer to show mine...but they work great.clip off the old wires,leaving about 4 or 5 inches,then add the connectors ,wires and new caps.

[ev0lution7]

do what i did .... get a drill and drill out the old ones use some copper wire shove down into coil and then shove better wires over the copper wire (i used some ROMEX scraps lying around) and drop a small amount of glue on the wire to the coil and you have a GREAT looking set of coils /w replacable wires....!

[cb(r)]

some bikes have pin that you can drill the old wire out mill the plastic away  and stuff the new wire onto.  I did this on my 92 fzr 600 and 71 cb350 twin.  both had wire issues but I machined the whole area away to have the pin completely exposed  the pin to make sure I had good contact.  btw the pin looks like a nail.

my coil on my 74 cb550 was actually a wire to wire solder.  it was more difficult to do but I still cut away the plastic and resoldered. I did this for cause of wire probs and just to see what happesn.  Sorry no pics of this one I might have one on me 350 though.  I have never spliced an old wire with a new one though

later

[JAG]

cool. thanks for the tips and advice..

I'd rather do what evolution7 did, since it would probably be better off, and it would overall look better than to have two wires spliced together.

So evolution7 did you shove the copper wire in there before you but the wires in for a better connection? I'm not exactly sure what it looks like inside the coil. Do you have to strip away the rubber from the wire before you place it inside the coil to allow for a better connection? Could you help me out a bit more on the details as to how the installation was achieved? I apologize, I just want to be able to get it done right. Pictures would be great, if possible.

Also if I can't do that I look up those NGK connectors and see how that process is done..

Thanks for the help guys..

JAG

[ev0lution7]

its very simple cut the wires (old ones) flush with the coil... then take a drill the same size as the old wires and drill about 1/4in INTO the coil were the old wires came out...
then grab some SOLID coper wire (Romex works good) just enough to have some stick inside the old wires (did you measure 1/4in when you drilled right?) and then push your NEW wires over the Copper wire (works kinda like a "post") then drop a small amount of glue on it to secure the wires to the coils and your done...

now on the business end of the wires you should get some NEW NGK plug boots that way you know that its a good connection you dont want to go though all this trouble and then find you have 1 bad sparky boot

BTW i got my set @ kragen it was ment for a 4cycl car but soemone lost the Coil Wire but it still had PLENTY of wire left and they were 8mm spiral core Accell wires w/ 150ohms per foot  and best part it was on clearance $10 for the box! anyways you can buy any set and do the same thing just mine were yellow i didnt really have a choice for the price!

[mystic_1]

Read the following thread, it contains info on replacing the molded-in plug wires, plus pictures and links to articles describing the procedure:

GL 1000 coils on CB 750 - anybody tried it ?


hth

mystic_1

[JAG]

Sweet Mystic


That was very helpful..  I found a write up that 'hcritz' <sp> did with pictures, and it seems pretty straight forward.

I just don't understand why it has to be done that way. Since there is a large needle that sticks into the plug, from inside the coil, that you simply can't just wiggle out the old wire, and put in a new wire and that needle hold it in place.

Has anyone heard of anyone else doing it that way, without having to epoxy this, and dremel that??? Maybe I'm just not understanding something, but it just seems like it would be easier than that. ??

 ???confused

JAG

[mystic_1]

I believe that the coil casings were injection-molded around the coils and wires.  In other words, they assembled the wires to the pins from the coils, then the parts were placed in a mold and molten plastic was injected to create the casing.  Therefore, there's somewhat of a bond between the plug wires and the plastic of the housing.  That, combined with the length of the embedded portion of the cable, says to me that if you just pulled without relieving the casing, the wire would simply snap off, leaving a stub inside the coil.

Mind you, I'm speculating here, I've never actually performed this mod, as I bought a set of OEM coils years ago when I first got the bike and they're working great.

mystic_1

[JAG]

Well that seems logical, since you put it that way. I had no idea it was put together that way..

I don't know if I trust myself enough to try cutting into the coils and all that. I'm trying my luck at some ebay auctions so maybe I can find a 'good' used one, for a cheap price.

I don't think my coils are necessarily the problem, just like you hear in most cases, my plug wires just look as if they've been gnawed on by some little dog, and are really in desperate need of changing.

[JAG]

I just won a set of coils off of ebay for $40 dollars, that looked to be in good condition, and the seller said it had been test and was in good working order.

Is that a good price for them?

Also got an airbox for $10. Figure if I have problems with the pods, I can throw that on there..

ebay always scares me, I always fear I am going to buy something that doesn't work, and being possibly ripped off.. oh well that's the nature of the beast I suppose..

Is there anything I need to be aware of when installing these coils when I get them? Is there anything I should do as far as testing them to make sure they are going to work? Or should I just be able to plug them up and go?!

Thanks for all yalls help

JAG

[andy750]

Plug them in and go....very rare for coils to be bad. Just make sure all wires hooked up correctly and wire ends have good contact with plug caps.

good luck
Andy

[mystic_1]

If you have a multimeter, it only takes a few minutes to to the basic coil tests listed in the manual.  If the resistance readings look good, and the wires are in good condition, you're probably all set.

$40 is way better than what you'd pay for a new OEM coil assembly, you could probably find them cheaper but not by much I'd bet.

mystic_1

[JAG]

I do have a multimeter, but I'm not sure why, because for the life of me I don't know how to use it!

SO if there is any kind of pointers you can throw my way to show me how to use it to test the resistence, would be greatly appreciated..

I apologize for my ignorance, I just have never used one before.

[mystic_1]

OK, so on the lower left side of your dial is a region with the symbol Ω.  This stands for Ohms, the standard measurement of resistance.  The different settings within this region are for selecting the maximum reading you expect to get.  Choose the lowest range that is higher than the readings you expect.  When you touch the test leads to each other, your meter should show 0 ohms, no resistance.  With the leads not touching, your meter will somehow indicate "infinite resistance".

So, assuming a 750 coil, the specified resistance for the primary winding in the coil (small wires) is 5 ohms, so set your meter to the next higher range, in your case the lowest setting, 200.  Now, touch your test leads to the small wires, doesn't matter which polarity, and your meter will show you the resistance.  If you don't get a valid number, you've either got infinite resistance (broken circuit) or your range is set too low.

Next, remove the spark plug caps from the ends of the plug wires (they just unscrew).  Expected resistance on the secondary winding (big wires) is around 15k Ohms, so set your meter to the 20k range  and touch your meter's leads to the two plug wires.  Read as before.

Finally, test the plug caps, one lead where the wire goes, the other where the spark plug connects.  The caps are supposed to have resistors in them, and expected resistance is (i believe) 5k-10k, so again use the 20k range.

Lots of good info on testing the coils in the Ignition & plugs FAQ

hth

mystic_1

[JAG]

First off, thank you so much for your help mystic.

I took off the caps and checked the ohms on the ends, and I got 14.55 on 1-4 and 15.67 on 2-3.. But for the life of me, I cannot figure out how to check the little wires at the coil as you suggested. I went ahead and took off about 1/4 of an inch off each wire to get a better surface, and noticed that the 1-4 plug caps will screw on and get tight, but 2-3 won't tighten up against the wire, meaning with any force I can easily pull off the cap from the wire. Now I don't know if that "slack" contributes to anything, but I would assume that some new caps are in order in able to fix that, wouldn't you agree??

Also seem to foul out the 4th plug.The only way I can tell is that the header won't get hot. I simply replace it with another spark plug and it gets hot, but that only seems to last for a hort while before I need to replace it with another one. I don't even buy new plugs, I just continue to switch back and forth between the two plugs..  Kind of weird 

[mystic_1]

Well, the spark plug caps attach to the wire with a small screw that winds into the wire as you twist on the cap.  Ideally you will feel some resistance when the wire bottoms out, but since we're talking about a steel screw threading into a rubber wire, this resistance will be pretty slight and you may not feel it.  The caps shouldn't be so loose that they basically fall off the wire, nor will the be so tight that it's like screwing into metal.  New plug caps are not terribly expensive, couldn't hurt to replace them.  I'm seeing sets of 4 available on eBay for $25 or so.

As far as #4 is concerned, sounds like your plug is fouling.  This could be caused by a number of things but since you're not seeing the same problem on #1, and since #4 and #1 share the same coil, points, etc, my feeling is that your coils are not the problem here.  To confirm this, swap the #1 wire and the #4 wire.  Since they both fire at the same time, you won't have to change anything else.  Do that and see if the problem follows the wire, or stays at #4.  If it stays at #4, your problem probably lies elsewhere, probably carb tuning. 

Was it doing this before you swapped the coils?


As far as testing the small wires at the coils, if the coils are disconnected already, just place one of your multimeter leads on each small wire.  There should be two wires per coil, one coil has yellow and black, the other could has blue and black.  if the coils are on the bike currently, disconnect the small wires from the bike's wiring before testing them.


best of luck!

mystic_1

[JAG]

If it stays at #4, your problem probably lies elsewhere, probably carb tuning. 

I have swapped the plug wires before, and I did them again and the problem does stay with #4. I thought it may have something to do with the fuel intake, meaning I have my float set wrong allowing to much fuel in. Because I have actually had this problem before, but on the  #2 cylinder. Once I changed all of the float heights it worked just fine.

I have a temporary set up with a spare tank that has fuel hoses that are actually a little to long, and when the bike is on the kickstand, it will sometimes actually have trouble getting fuel to the number 4 carb. And since, in theory, the gas simply runs out of the tank via gravity, it may be have some difficulties getting to that number 4 carb, which, again in theory, may be allowing it to receive inconsistent levels of fuels. When I take the spark plug out after seeing that the header isn't getting hot, and see that the plug is wet, which I assume equals to much fuel. When I replace it with another plug, the header will heat up, and collectively all for headers are running at a temperature of 370 degrees. Now I don't know if that is to hot/ to cold, but I'm just happy to get it all the same. Of course that seems to always be short lived, because the plug will again foul out.

I am going to try to reduce the travel of the fuel lines to allow for faster/consistent delivery of the fuel, and see if it helps things. I know I am in need of a sync again, since I have been messing with the carbs so much, but the last time I had it done, the mechanic said that they were already close to perfect that he didn't do much to them. So my bench sync and everything else seems to be fairly accurate. The sync is just hard for me to get done, because I don't have the money to buy one, nor do I have the money to have it done.


Was it doing this before you swapped the coils?

I haven't actually swapped coils yet. I just won them on ebay so it'll be a while before I get them home. I just always assumed that the coils were the culprit, but like you said it really isn't if the problem doesn't follow the plug wire.

It's weird how everything is just a trickling/snowball effect. If one thing is off, it sets the course for a numerous amount of things to be off.