Spark plug cap tear down & new wires & plugs

R. J.

R. J.

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:hello: Since my tank was off for hose replacements I removed the coils, wires & plugs. I installed new plugs & wires. I took apart the spark plug caps for cleaning. Checked the 5 K ohm resistors. Inspected the springs & put a dab of dielectric grease on the parts & reassembled them. I had 7 spark plug caps given to me. 2 new ones & 5 used ones. Only 2 of the used ones was not dry rotted. I stripped the bad ones of all the internal components & tested the resistors for 5 K ohms. They all ranged form 4.8 to 5.3 K ohms. The insert that holds the spring & resistor can also be removed for inspection of cracks & corrosion. It is a good idea to clean the inside of this insert/retainer because carbon deposits & other foreign matter can find its way into it & restrict current flow. Sometimes after reassembling a spark plug cap you can get a open reading on your meter because of foreign matter that makes its way into the insert. The insert is the ceramic/plastic part that houses the 5 K ohm resistor & it's components. After reassembling a spark plug cap recheck it for 5 K ohms. This test applies to the ZL 900 & ZL 1000. When using old spark plug wires cut about a 1/4 inch from each end. It is best to go ahead & replace the wires with new 7 MM copper core wire.
 

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SPARK PLUG TEAR DOWN 101 with your host RJ:clapping::clapping:
Good thread RJ...alot of guys dont even know about the resistor in the cap:thumbsup:
 
:hello: A few weeks ago my one friend Bob's ZL 1000 motor was intermittent on cyns 3 & 4. Trouble-shooting lead to the finding of the plastic/ceramic inserts on those to cyns spark plug caps was cracked causing the problem. I gave him two good usable spark plug caps. First we dissembled them. I cleaned the inside of both ends of the cap with a mixture of baking soda & distilled white vinegar. Use 2 table spoons of baking soda to one cup of vinegar. Next I sprayed both ends of the stripped caps plastic inserts that house the spring, 5K ohm resister & brass spark plug retainer gizmo while it was still inside the outside insulator with carb cleaner. Then I used air to dry the insides. Sometimes foreign matter can find it's way inside causing restriction. Then I cleaned up the brass threaded gizmo on my grinders brass wire wheel. Next I put dielectric grease on the other parts & resembled the spark plug caps. Then tested for 5 K ohms of resistance. I also gave him new spark plug wires. Here is a pic of the broken caps.
 

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rj, very nice write up,,so thats the only way to test the ohms is taking it apart.
 
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"so thats the only way to test the ohms is taking it apart."

No, each wire + cap should measure approx. 5K ohms end-to-end when fully assembled.
 
:hello: After reassembling the caps with spark plug wires check again for 5 K ohms. Post # 1 pic # 1 I have the one coil facing the wrong way. I numbered each spark plug wire to it's associated coil with a silver sharpie before taking them apart.
 
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" I had 6 spark plug caps given to me. 2 new ones & 5 used ones. " :rotf::rotf::twisted::biggrin::laughing8:

Sorry just had to giggle at that one :thumbsup:
 
:hello: In pic one of post one the reason one coil is backwards is form the P O. He shortened the plug wires to much so instead of spending a few dollars on new wires he reversed the one coil. I can buy copper core 7mm spark plug wire @ 0.58 cents a foot from our local old school auto parts/machine shop.
 
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If you remove the plastic/ceramic insulator from the spark plug boot for inspection when reinstalling it smear a wee bit of dielectric grease on the insulator before sliding it back into the spark plug boot. This makes the process go much easier.
 
R.J. would you be interested in redoing my wires if I send them to you.
 
OLD and don't think there working the way they should. Seems like bike doesn't run on all cylinders unless on it hard. one of the wires dont fit very tight onto the plug any more. Got water down the spark plug hole from washing it. want to replace the ends and wire.
 
:hello: Kevin I sent the spark plug cap today along with 5 ft. of new 7 MM copper core plug wire. Sorry for the delay but I really haven't left the house since we talked last. You should see the package this Sat. Make sure you take the cap apart & clean all the internals. Check it for 5 ohms & dialectic grease all the parts before putting it all back together.
 
Will keep my eyes on the mail box. Thank you so much for all the help. It really helped me reading up on your post about the rebuilding of plug wires. I know that the ZL-OA site with all the help that it's members do for each other, is one of the best examples of people working together to do what inspires us all. A big thank you goes out to you and the rest of the members.
 
Yes I did thank you. I worked on them yesterday. almost got them done. Just have to feel a little better to finish them up and install them. The weather here has been great. Wont be long and I will be able to go for a ride.:)
 
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