Dielectric grease question

Mr. Detail · Post by **Mr. Detail** » 08 Jan 2020, 06:24

No jokes now.
I was able to complete and install five new ignition coils last night but in my ignorance I did not notice the tiny packet of dielectric grease at the bottom of the box. The instructions stated that it was not necessary to apply this but I wanted to hear your opinion.
If you do suggest that I re-pull the coils, where do you apply the grease? With a Q-tip on the inside diameter at the bottom of the coil?

Post by **- Pete -** » 08 Jan 2020, 07:14

I’ve never bothered with it, but it couldn’t hurt. I’ve also never bothered with anti seize on the plug threads.

Whoever changed the plugs last on our VR musta really globbed it on the threads. I can’t stand this. It ends up making it difficult to remove plugs (feels like threads are stripped as you have constant resistance the entire way backing it out). Also once out you have a nice little mole hill of dried up solidified gray anti seize crumbs that will inevitably fall back into the cylinder if you’re not ultra careful.

Edit, I believe there is special high temp anti seize specifically for spark plugs like applications that won’t solidify like the cheap gray stuff, but still, I just leave them dry. There’s tons of arguments for and against this online across a multitude of fora.

Post by **pgill** » 08 Jan 2020, 07:48

Mr. Detail wrote: ↑08 Jan 2020, 06:24 No jokes now.
I was able to complete and install five new ignition coils last night but in my ignorance I did not notice the tiny packet of dielectric grease at the bottom of the box. The instructions stated that it was not necessary to apply this but I wanted to hear your opinion.
If you do suggest that I re-pull the coils, where do you apply the grease? With a Q-tip on the inside diameter at the bottom of the coil?

I put the Dielectric Grease on the ceramic insulator of the spark plug in the location shown by the blue box.

Because the sparkplugs are hidden down the well I use a magnetic tool to hold the plug in the socket during install.

The purpose of the grease is to minimize the current that leaks past the sparkplug.

You want as much of the current jumping the gap of the spark plug as possible.

Because you already have everything together you can remove the coil packs and put some grease on the end of the insulator so that it will seal to the ceramic of the sparkplug.

: dielectric.jpg (64.86 KiB) Viewed 3467 times

Good Luck

Paul

Post by **- Pete -** » 08 Jan 2020, 10:25

+1 on a dab to the ceramic. Meant to say that if you use any to use it there but got sidetracked with plug thread antiseize.

Post by **pgill** » 08 Jan 2020, 11:16

In the past I was using a spark plug socket with a rubber insert to hold on to the insulator during removal and install.

This type of socket prevents the application of the dielectric grease on the top of the insulator

Because I wanted to put dielectric grease on the insulator I bought the following tools.

Now the magnet holds the sparkplug electrode and nothing is in contact with the ceramic.

https://www.amazon.com/gp/product/B07CM ... UTF8&psc=1

https://www.amazon.com/gp/product/B000K ... UTF8&psc=1

Take care

Paul

Post by **- Pete -** » 08 Jan 2020, 18:50

Nice, thanks for posting that magnetic extension link Paul. Might have to add that one to my cart for such a low price.

Post by **oragex** » 08 Jan 2020, 19:24

The electrical connector to the coils has that rubber seal that's quite water proof. One thing good to know is the coils appear to have a rubber jacket around the spark plug coil - this jacket is not water proof. It may be, but it may also let water enter down the plug hole. I've experienced this after trying to wash the top of the engine (I know, bad idea), I got water inside the plug holes, not fun to remove (and also blew a coil by the same).

Post by **pgill** » 09 Jan 2020, 08:15

oragex wrote: ↑08 Jan 2020, 19:24 The electrical connector to the coils has that rubber seal that's quite water proof. One thing good to know is the coils appear to have a rubber jacket around the spark plug coil - this jacket is not water proof. It may be, but it may also let water enter down the plug hole. I've experienced this after trying to wash the top of the engine (I know, bad idea), I got water inside the plug holes, not fun to remove (and also blew a coil by the same).

Excellent point!!!!

If water can get in then Dust can get is as well. (Water and dust are not electrical insulators at 40,000 Volts)

At 40,000 Volts the insulation needs to be very good (the dielectric grease helps, new spark plugs with a clean ceramic insulator helps)

For me personally I don't touch the ceramic when I install the spark-plugs.

And I clean the spark-plug wells when I change the plugs.

Based on what I've read the engine management computer will drive the coil packs harder (more current) if it detects misfires.

By doing this the life of the coil pack will be shorter.

To mitigate this I do everything I can to optimize the spark-plug to coil pack connection.

I will add to my list to check the dust seal between the coil pack and the Valve cover.

Great tip!!!! Thanks for pointing that out.

Paul

Post by **BlackBart** » 10 Jan 2020, 14:05

pgill wrote: ↑09 Jan 2020, 08:15 And I clean the spark-plug wells when I change the plugs.

How, without dropping grit down the hole? I've thought about a small nozzle on a shopvac.

deano1 · Post by **deano1** » 10 Jan 2020, 15:58

"I've thought about a small nozzle on a shopvac".

Yep!
I have a thingamajig i cobbled up from progressively smaller tubing so that i can do that very thing. Especially after chasing spark plug threads to remove old anti-seize from on top of piston. Yeah,Yeah I know it gets blown out on the first exhaust stroke but i do it anyway.
Stay curious my friends