Dielctric Grease
Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
I know this is an old thread but hey its here and Im waking up to my coffee. Another product I use is Sil-glide. Silicone waterproof grease.
Id like to comment on the spark plug toque, I remember Ford had (has) an issue blowing plugs is by the poor design of the thread depth in the heads. V-10's were notorious, then they came out with their own thread insert kit. But in reference to using lube on threads and over torquing, if dry torque is speced than any lube on threads requires a reduction in final torque. For example the charts I use to go with say when torquing steel into aluminum (spark plugs) the torque has to be reduced by 40%.
I have always used never seeze or motor oil. Book states that, which means the torque spec is factored for lubed threads.
Id like to comment on the spark plug toque, I remember Ford had (has) an issue blowing plugs is by the poor design of the thread depth in the heads. V-10's were notorious, then they came out with their own thread insert kit. But in reference to using lube on threads and over torquing, if dry torque is speced than any lube on threads requires a reduction in final torque. For example the charts I use to go with say when torquing steel into aluminum (spark plugs) the torque has to be reduced by 40%.
I have always used never seeze or motor oil. Book states that, which means the torque spec is factored for lubed threads.
Advanced
Joined: May 2010
Posts: 93
Likes: 0
From: Central Michigan
How about using simple Vaseline? I've done this with no ill effects. Admittedly, this is not ideal but the original question asked about what could be used if no dielectric grease was around.
G'day,
Vinish
G'day,
Vinish
Seasoned HDF Member
Joined: Sep 2013
Posts: 6,175
Likes: 1,966
From: Great State of Canada
Not on rubber !
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
Dielectric grease on spark plugs?? Wouldn't be my choice. I use an antisieze lube on mine.
It can handle high temps and prevents galling, corrosion and seizing.
This one or similar:
Amazon.com: Permatex 81343 Anti-Seize Lubricant, 1 oz. Tube: Automotive
It can handle high temps and prevents galling, corrosion and seizing.
This one or similar:
Amazon.com: Permatex 81343 Anti-Seize Lubricant, 1 oz. Tube: Automotive
If a car is going 80 miles per hour.........
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
Yes, I have two Ford 4.6 engines, one has 265K on it, I last changed the plugs at 150K, and they came right out...Time to change them again.
Ford 4.6 engines are notorious for having weak spark plug threads that are damaged from over torquing, there is a technical service bulletin that specifically states not to use anti seize.
Ford forums are full of threads about 4.6 engine spark plugs blowing out of the engine.
That`s why I posted that most engine manufacturers and spark plug manufacturers don`t call for anti seize.
The HD manual says to use anti seize, so there is no problem.
https://www.ngksparkplugs.com/about-...ut-spark-plugs
I wish I would have known about dielectric grease when I was youngster working on my old cars, those spark plug boots would be stuck to the plug like they were part of it...
Ford 4.6 engines are notorious for having weak spark plug threads that are damaged from over torquing, there is a technical service bulletin that specifically states not to use anti seize.
Ford forums are full of threads about 4.6 engine spark plugs blowing out of the engine.
That`s why I posted that most engine manufacturers and spark plug manufacturers don`t call for anti seize.
The HD manual says to use anti seize, so there is no problem.
https://www.ngksparkplugs.com/about-...ut-spark-plugs
I wish I would have known about dielectric grease when I was youngster working on my old cars, those spark plug boots would be stuck to the plug like they were part of it...
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Advanced
Joined: May 2010
Posts: 93
Likes: 0
From: Central Michigan
Agreed, no vaseline on rubber and not on sparkplug threads either. But putting it on the normal electrical connections would seem okay (not rubber). What about using it on the electrical connection of the spark plug (remember, this was an "emergency" where there is no dielectric grease around)? If you keep it just on the metal connection point on the sparkplug, it would seem that contact with the rubber sparkplug boot would be minimal. Might work in a pinch.
G'day,
Vinish
G'day,
Vinish
Outstanding HDF Member
Joined: Nov 2008
Posts: 2,034
Likes: 128
Dielectric grease on spark plugs?? Wouldn't be my choice. I use an antisieze lube on mine.
It can handle high temps and prevents galling, corrosion and seizing.
This one or similar:
Amazon.com: Permatex 81343 Anti-Seize Lubricant, 1 oz. Tube: Automotive
It can handle high temps and prevents galling, corrosion and seizing.
This one or similar:
Amazon.com: Permatex 81343 Anti-Seize Lubricant, 1 oz. Tube: Automotive