The cause is the aluminum head, heat stress magnaflux inspections indicate. The most occurances are after the factory plugs are replaced, recommended @ 100k miles by FORD, same time power tran warranty runs out. Heat build up over extended driving, like 3 of mine did, each @ the last hr of a 12 hour drive. The blowout of the plug takes out the coil pak, occurrs on all engines of the earlier modular design from 4.2L to V10s. Timeserts fix.

 

4.2 is not considered a modular and the plugs dont blow out of it. There are lots of aluminum heads out there that the plugs dont blow out.. There are several reasons it happens. Loose coils damaged/cross threaded plugs under torqued.. Many members on the bord have hundreds of thousands of miles with out blow outs. Theres generally a reason it happens.

 

Sears sells the deep socket.

 

I had mine replaced by the Ford dealer @ 92k miles. I checked the torque after the installation all were good. In 2009 there were over 8000 owners of these engines with blown out plugs after original plug replacement in the 2V motors to date! All aluminum heads are not the same. I had a Chevy Vega, aluminum heads, famous for problems, mine never had a problem. Can't make a gneral statement on anything always an exception. FORD didn't do a re-design for nothing! A rudimentary analurgic inspection of the 2V and 3V heads will indicate a different aluminum material! I installed timeserts in all plug wells, 15k miles later, several 12 hour trips, no problems!

2002 Supercrew Lariet 5.4 117k miles

 

I can only speak from my own experience and that was I had a blow out on #7. The coil bolt felt like it was tight but the bolt wasn't going all the way down the coil was loose. I've seen other people have the same problem have blow outs because the little coil bolt wasn't tight or was striped. There are other reasons it happens. They should have used more threads for sure but if every thing is right they hold.

 

No, the 2.3 Vega engine had an aluminum block with an iron head. Dissimilar metal expansion went through head gaskets, and the siliconized bores with no liners got eaten up by ethylene glycol. Overheat it once and scrap the whole engine. BAD engine all the way around.

 

After reading all of this, I recall that I had #3 blow-out in Oct. 2008. I had a heli-coil put in. 60,000 miles later, still no problems. Questions: If I attempt a plug change, am I going to pull the heli-coil out with the plug? If I need to replace Heli-coil with timesert, is it going to be a problem?

 

Heli coil not recommended. Good its lasted this long though. Good chance it can pull out. Since timesert is larger, you can easily replace the heli coil with it.

 

elkitino...read this thread currently running (and imbedded links) if you haven't already.

https://www.f150online.com/forums/sh...d.php?t=465519

You should be in good shape when (notice I didn't say "if") you have problems. But, you're in luck as the TimeSert will usually fix a heli-coil hole. I've covered that a quite a few times.

 

Unfortunately it looks like i have joined the club. Not once but twice!! I had the #2 blowout last saturday. Fixed that one. Now one week later #3 decides to go. Hope thats it for me. Both my blowouts happened when starting a cold engine. Dont know if thats coincidence or if there is something to that?

 

You probably have improperly torqued plugs. I hope you are using Timesert to fix it......

 

I have no idea why anybody would think that the coil would have anything to do with holding the plug in. There is no way a loose coil bolt has anything to do with blown plugs.

 

Because there are those of us who have seen it happen more then once. Loose or striped coil boot and the coil bounces around. Slowly over a year or 2 it works the plug loose. It happens. Happened to me.

 

Okay, I suppose that could be. Maybe I shouldn't have been so definitive. But something in the back of my head is saying those plugs probably would have let go anyway. Just curious here, why would you watch a loose coil bounce around for a year or two and not put a socket on it?

 

Its not like they jiggle around right in front of you.. In my case the bolt felt tight. It was only after the plug ejected I pulled all my coils and plugs to check torque. when I put the coils back on I noticed the coil for the ejected plug was loose it moved very loosely even though the bolt felt tight. I got some washers so the bolt would secure the coil. The coils are mounted on a bushing and your suppose to be able to move them but they should move very snugly. I've seen board members here who have stripped the bolt and just left it like that and had blow outs.