I usually can find the answer to my questions by a quick search but I am still confused with this one. I have a 1997 Jimmy 4x4 with 166,000. I'm getting ready to do a tuneup. I have an AC Delco cap, rotor, wires, and plugs. I purchased some Dielectric grease. I read in a few posts to apply the grease to the ceramic part of the plugs, but I'm confused with where to put the grease on the cap. Do I put it on the outside of the cap where the wires connect AND on the inside of the cap on the posts and rotor?

 

why would you put dielectric grease on ceramics? when you use it you put it on the electrical contacts of the plugs and or wires and rotor. it is used to keep moisture off of the metal contacts. any where you have metal parts making contact you can use it. this includes loading up the battery posts as well.

 

i wouldnt put it on the inside of the cap. ideally you should never have any moisture in there anyway.

 

I really have no idea which is why I'm asking. I read that you put it on the spark plug insulator and it keeps the boot for fusing to the plug.

This is my first tune-up and I'm just trying to do it right the first time.

 

Just put a dab in the boot on each end of the wire and you'll be good. One thing to remember is that with grease in the boot, you can end up with trapped air that could push the boot off the plug/cap when the air heats up. A small 'J' of wire slid into the boot while you put it over the terminal or plug can allow the air to escape and then be easily slid out.

 

Got it. Thanks guys