quick question, loctite on spark plugs

jimfitzgerald said:
People from MD came over here to tell you guys you were getting some bad advice from Mike, regardless if it came from Ford or not. Some of you still don't seem to understand that Ford is just trying to save themselves some warranty money. You don't have to know Mike personally to know his advice, in this case, is not good. That's not a personal attack on anyone. As far as correcting his spelling and grammar, that was meant to be funny, but as someone pointed out, it also reflects on a person's credibility. You guys go ahead and use loctite if you want. Weld the suckers in for all I care. :cheers:

NO do not use locktite. i am retracting this now after what i saw today on a test i did. and i showed it too my boss.

to start off i take responsiblitiy of this but we were told to do this on new lightings ( by ford back in 2002-3) and was recomended to use this method for all mod motors.

it turns out that while the locktite does stop the plug from loosening and backing out. it can cause some thread damage. i must of got lucky on my car.

i took a 5.4 with a spun bearing we had in the shop. this motor had plugs put in by us at 100k miles with locktite and the motor was pulled at about 139,000 i removed the plugs from it as a test 7 of the plug holes the threads were fine. one of them showed some thread damaged. and upon closer inspection i think this could have been caused by the locktite.

i showed this my boss who was working today. and we are going too look into it.

i think when this was told too us by ford they knew that the locktite will stop the plug from backing out. but they probally never considered removal. they were proballly only concerned with stoping the plugs from backing out and with a 100k plug they figure it will be well out of warrenty.

i gave ford a little more credit than they deserve and took this as meaning that it's safe. i must have gotten lucky on the ones i did remove

well i have used locktite now on a few mustang and lightings i work on personally and if a problem comes up i am going too get them free heads.

i checked mine again and showed no thread damage. so i put in another set of plugs after i cleaned the threads.

so now the only thing i can think of is the tried and true tourqe it down too spec and recheck them once in awile.

well i am not perfect and i doubt many of us are.
 
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MikeZ28 said:
NO do not use locktite. i am retracting this now after what i saw today on a test i did. and i showed it too my boss.

to start off i take responsiblitiy of this but we were told to do this on new lightings ( by ford back in 2002-3) and was recomended to use this method for all mod motors.

it turns out that while the locktite does stop the plug from loosening and backing out. it can cause some thread damage. i must of got lucky on my car.

i took a 5.4 with a spun bearing we had in the shop. this motor had plugs put in by us at 100k miles with locktite and the motor was pulled at about 139,000 i removed the plugs from it as a test 7 of the plug holes the threads were fine. one of them showed some thread damaged. and upon closer inspection i think this could have been caused by the locktite.

i showed this my boss who was working today. and we are going too look into it.

i think when this was told too us by ford they knew that the locktite will stop the plug from backing out. but they probally never considered removal. they were proballly only concerned with stoping the plugs from backing out and with a 100k plug they figure it will be well out of warrenty.

i gave ford a little more credit than they deserve and took this as meaning that it's safe. i must have gotten lucky on the ones i did remove

well i have used locktite now on a few mustang and lightings i work on personally and if a problem comes up i am going too get them free heads.

i checked mine again and showed no thread damage. so i put in another set of plugs after i cleaned the threads.

so now the only thing i can think of is the tried and true tourqe it down too spec and recheck them once in awile.

well i am not perfect and i doubt many of us are.


Way to go!

I never had any doubt that the Ford rep didn't think about the long term effect of loc-tite, nor the removal of the plug installed with loc-tite. They were only thinking of the short time solution.

I was told YEARS ago to put anti-seize on the plugs because they are made of iron/steel and the head is aluminum. The two metals heat/cool at different rates, and there is a chemical process that can occur and seize the plug to the head. In 1999 I found this out the hard way by having NOT used anti-seize. When it came time to remove the plug, I broke it clean off in the head. The ceramic along with the nut snapped off, leaving the threads and the tang inside the head. No matter what I did, it would not come out. I had to take it to a shop where they removed the head and had it machined. To this day, I use a little dab of anti-seize on every aluminum head when installing plugs.

I'm sorry to have crossed you, but it was your info that I had a problem with, not necessarily the messenger.

Matt
 
03trubluGT said:
Way to go!

I never had any doubt that the Ford rep didn't think about the long term effect of loc-tite, nor the removal of the plug installed with loc-tite. They were only thinking of the short time solution.

I was told YEARS ago to put anti-seize on the plugs because they are made of iron/steel and the head is aluminum. The two metals heat/cool at different rates, and there is a chemical process that can occur and seize the plug to the head. In 1999 I found this out the hard way by having NOT used anti-seize. When it came time to remove the plug, I broke it clean off in the head. The ceramic along with the nut snapped off, leaving the threads and the tang inside the head. No matter what I did, it would not come out. I had to take it to a shop where they removed the head and had it machined. To this day, I use a little dab of anti-seize on every aluminum head when installing plugs.

I'm sorry to have crossed you, but it was your info that I had a problem with, not necessarily the messenger.

Matt
Now see? That's what I'm talking about. Refute info without attacking character.

You are exactly right about the use of anti-seize to prevent the plugs from fusing itself into the head. When I did electrical work we used a similar material on the copper wire to prevent aluminum rust on the aluminum buss. Two disimilar metels under heat could cause a failure by reducing the conductivity. By using anti seize it has the same effect by preventing the rust and seizing the plugs to the head.

As a side note I have sent an email to the makers of loctite to see if they recommend or not using this particular product for this purpose although it looks like it has mostly been refuted now. I post up when they have replied.
 
03trubluGT said:
Way to go!

I never had any doubt that the Ford rep didn't think about the long term effect of loc-tite, nor the removal of the plug installed with loc-tite. They were only thinking of the short time solution.

I was told YEARS ago to put anti-seize on the plugs because they are made of iron/steel and the head is aluminum. The two metals heat/cool at different rates, and there is a chemical process that can occur and seize the plug to the head. In 1999 I found this out the hard way by having NOT used anti-seize. When it came time to remove the plug, I broke it clean off in the head. The ceramic along with the nut snapped off, leaving the threads and the tang inside the head. No matter what I did, it would not come out. I had to take it to a shop where they removed the head and had it machined. To this day, I use a little dab of anti-seize on every aluminum head when installing plugs.

I'm sorry to have crossed you, but it was your info that I had a problem with, not necessarily the messenger.

Matt


yeah that sucks when a plug seizes in. used too happen on the old 5.8's in the f-series and broncos a LOT. in fact it happend so often that when we saw one come in for a tune up we warned the customer about the chances of them breaking off.

on the bright side the modular head does not seem too have problems with seizing the plugs in.but a dab of anti-seize will not hurt.
 
crew_dawg16.

yeah it been known for along time that the heads had a design flaw. for the most part this was the early heads. and was only a problem on the 5.4's but some of our 4.6's are shooting the plugs out now.

i am not surprised the problem showed up first on the motors with the highest cylinder presures. like the S/C lighting and the 5.4 F-150 motor ( a motor with less overlap will have high cyl. presure) the new 2003+ heads have more threads to fix this problem. but where does that leave the rest of us ?

no matter what the plugs on these motors will back out. even if tourqed right it can happen. and since the loctite idea can cause damage that can't be done.

the only thing we can do is tourqe them too spec and check them once in awile.
 
You THE MAN !!

MikeZ28 said:
NO do not use locktite. i am retracting this now after what i saw today on a test i did. and i showed it too my boss.


I am proud of you Mike, takes a man to fess up on bad info. (you where not wrong, just miss led)

Ant-seize as been used for years on imports, so if you didn't know that I can see why some people don't use it on the Mod Motors.

Owning your own business, you tread very carefully as the labor is FREE the second time. Dealer could care less IMOP, been their done that.

Cool thing about the Military, if you screw up their is nothing they can do if you used the proper Tech data. :flag:

In closing, thanks for your Tech advice ! :nice:

(In the field no SP check,sorry)
 
Cavallo said:
MikeZ28 said:
NO do not use locktite. i am retracting this now after what i saw today on a test i did. and i showed it too my boss.


I am proud of you Mike, takes a man to fess up on bad info. (you where not wrong, just miss led)

Ant-seize as been used for years on imports, so if you didn't know that I can see why some people don't use it on the Mod Motors.

Owning your own business, you tread very carefully as the labor is FREE the second time. Dealer could care less IMOP, been their done that.

Cool thing about the Military, if you screw up their is nothing they can do if you used the proper Tech data. :flag:

In closing, thanks for your Tech advice ! :nice:

(In the field no SP check,sorry)


i should have checked out the locktite info a lot more before suggesting it.

ohh well it was caught fast enough that even if somebody used locktite it could be removed now.

live and learn. i am still very disapointed something that would effect the long term serviceablity of the car was suggested by them.

but on the other hand i see why they would not care. first plug change is at 100k. so if they were done at the dealer when new ( as was suggested on lightings) the truck would have 100k on it before the problem came up. sure the plug would not blast out. but you will have a chance of not getting another plug in there. at 100k miles thats your problem not theres.


and about anti-seize. yeah i have used it on iron head trucks and cars for years. works real well on the 5.8 truck motors that seize up bad.

i have never had a problem with a correctly threaded plug seizing into a modular head. and because of that and the problems with them rattling loose i have never used anti seize on them.
 
E-mail I recieved from the makers of Loctite. I'm still beating this horse but thought I'd share...

Subject: Loctite Request Number 50054
To: [email protected]
From: [email protected] Add to Address Book
Date: Tue, 31 May 2005 10:38:56 -0400


Rick,

Thank you for your inquiry. Generally, you don't put a threadlocker on
the
spark plug itself. Rather, a helicoil is usually bonded into the
existing
threads using a high-temperature product like 620. However, if you want
to
use something specifically on the spark plug threads, most of our
products
are good to about 300F, with some, like the 620, good to 450F. These
are
permanent products that will likely need heat and force to remove.

Please feel free to contact our Technical Information department
directly
at (800) 562-8483 if you would like to discuss in more detail.

Regards,

Cathy
 
MikeZ28 said:
Cavallo said:
i should have checked out the locktite info a lot more before suggesting it.

ohh well it was caught fast enough that even if somebody used locktite it could be removed now.

live and learn. i am still very disapointed something that would effect the long term serviceablity of the car was suggested by them.

but on the other hand i see why they would not care. first plug change is at 100k. so if they were done at the dealer when new ( as was suggested on lightings) the truck would have 100k on it before the problem came up. sure the plug would not blast out. but you will have a chance of not getting another plug in there. at 100k miles thats your problem not theres.


and about anti-seize. yeah i have used it on iron head trucks and cars for years. works real well on the 5.8 truck motors that seize up bad.

i have never had a problem with a correctly threaded plug seizing into a modular head. and because of that and the problems with them rattling loose i have never used anti seize on them.

Damn Mike, you can't recant now! I just loc-tited all of my plugs, then I supreglued my hood shut! J/K... Thanks for double checking and bringing it to everyones attention. :nice: