hi everyone.
trying to look for patterns in spark plug blow out.
can you post info on your blowout? how many plugs, what cylinder, how long apart, wheather and driving style at time of blowout. was it factory plugs or did they blow after putting new plugs.
i year ago i blew the # 8 cyl a week ago # 4 blew. both were during cold wheather 50-60 degrees. both on highway at 65 mph cruise control. most recent blowout at 150, 000 miles. these were not original plugs. thanks in advance

 

I'm not sure if there is any pattern to which one blows out. My dad had his number 7 blow out, summer time on a 200 mile trip where I was following him. Truck had the plugs in it from purchase, not knowing what they were torqued to. I think the general consensus is that it is due to the lack of threads in the head and the factory torque recommendations, regardless of who installed them, if anytiseize and 13-15ft/lbs or whatever it was were used... there was a chance they would come out. I have not heard of ANYONE who has used the now recommended no antiseize and 28ft/lbs and had one blow out.

 

the only reason they pop out is due to lack of torque

 

I agree....Never had any of mine pop out. Just gotta wrench the **** out of em.

 

I had a blow out a week after having the dealer install new plugs in my van. I had just bought it and wasn't familiar with the 5.4's tendency to blow them out so when the service writer at the dealer told me they have that tendency I went off on him told him your F-n tech didnt tighten them. I still think he didnt..
People who torque the plugs to 28lbs dry-no anti-seize tend not to have blow outs. The ford recommendation is for like 14lbs. Not tight enough.

 

i have heard the not torqued enough theory.
I have also heard the torqued too much theory (alluminum threads get weakened after over torqing.)
All of you guys disagree with this over torqing theory?
2 days ago i torqued them to 14 no antiseize. Never used antiseize on a plug.

 

No, - over torquing is non existent, -as far these heads are concerned. They were bench tested @ 100' lbs and that didn't stretch or shear the threads. You'll break the plugs ceramic seal before 100' lbs. 28' lb's dry is perfect for tapered plug design.

 

don't want to "steal" a thread, but does the same apply to an '03 4.6 2 valve?

 

150,000 plus miles.
Never lost a plug, never used anti-seize on them also torqued them in good!
Now the plastic intake gave out on me on the chassis dyno! LOL!

 

I've been doing this for a while and very familiar with blown plugs in our motors...there is no pattern that I have seen.

 

my 2 plugs that have inserts can be put at 28 also?

 

Depends on what kind of inserts they are. The only ones that last are Timesert or the custom inserts installed by blownoutsparkplug.com.

Definitely. In 03, you may have 4 or 8 thread heads, doesn't matter though.

 

in the 1st one i have some old school insert from the 70's that is subposed to be quality. the most recent was a napa heli coil.

 

Time sert is the correct fix. anything else is a time bomb.

 

Although you can get good product thru Napa, Heli-coil isn't one of them. Napa needs to get with the program and offer Time sert. Some shops might while others don't. My Uncle owns two Auto supplies, he offers both, but offers Timesert as the better fix and permanent. Heli coil can be permanent fix for other applications, but it is not one for plug chamber repair.