Folks,

I am going to have to replace my COPS once again, though I have done it before, I was mystified by the correct application of grease to the boot and/or the plug. I have once again searched the interwebs and have not found consensus.

Can anyone tell me the proper application of DG to the COPs on a 2005 F150.

Thanks and sorry in advance.

 

The factory service manual simply states:

 

I like to use a q-tip to apply a thin application inside the boot right at the opening. You do not want any dielectric grease on electrical contact surfaces.Optional is a lite dab rubbed on the plug ceramic body groves. KM

 

you're just trying to prevent the boot from sticking to the plug and seal it off from moisture. Like they said - just some around the opening or on the ceramic is fine

 

... and don't worry about getting it on the contact surfaces as mentioned. The dielectric grease will be displaced by the metal contacts and still allow a good electrical connection.

 

I have a jar of Silicone Paste that I use to service the seals of the panoramic sunroof.
I used a dab of that on the boots that I replaced. Like mentioned previously here, just a tiny dab at the boot is sufficient to coat the plug to prevent the boot from sticking next time. A q-tip. Tip of a small screwdriver, etc, all work nicely.

Not sure if it is worth asking, but curious why you are changing coils 'again'. Again means you've already used up 2 sets of coils which isn't 'normal'.

I replaced the boots when I changed plugs but probably didn't need to but for a few bucks a piece I don't mind. But replacing coils gets expensive.

If you aren't using MotorCraft coils, maybe time to buy your last set and go with motorcraft.

 

I have a random wandering misfire, tried to replace plug and spring/boot of the first cylinder that showed up, and the plug was really (surprisingly) fouled…so I am replacing all plugs and cops with new, for the same piece of mind you mention. And it is my understanding the dialectric is, in addition to keeping the boot from sticking to the plug, it also keeps the plug from arcing to the engine, right?