My spidey senses went off a few weeks ago and told me to check the plugs on my Jeep. So I bought the plugs and a Torque Wrench just in case and decided to look at the plugs today. Big adventure for me since I'm used to the old school wires and distributor. I have resisted doing this since I have owned the Jeep. New plugs were badly needed, but I didn't know about that o' ring on the coil and the first one that I removed, tore. I put some dielectric grease on it to hold it in place reinstalled it and went looking for replacements. They are discontinued as far as the web goes. My local Jeep dealer managed to get me 8 at about 6 something each. I was not able to find an aftermarket supplier. I have read that some run without them and that may do in a pinch, but if the coil works without them. Why are they there? Is it an insulator for electricity or to stop liquid, water gas etc. from draining down into the spark plug hole?

 

I may be wrong, but I believe it's just a weather seal. You can take one to any hydraulic supply place or anywhere that sells 0-rings and get new ones. They aren't anything special. They are only worth about 50 cents each!

 

Thats what I thought. In doing my research though I found a couple old posts on-line with statements to the effect that said, save yourself a lot of trouble and just get them from the dealer. I didn't think that they were anything special, just hard to find so I took the easy route. They are already ordered so when they come in i'll run down to the local hose company with one and see what they come up with.