What year did ford revise the heads to cure the spark plug blowout issue?

Mainly on the 4.6L

 

I only heard of the 5.4s having this problem for the most part. It was mainly with the plug/s that was the two piece deal. If it was an issue with a certain year, I dont know for my 98 4.6 has never had an issue and she has around 182k.

 

when they went to the 3v motor and came out with spark plugs that got stuck in the head

 

If I'm in error here someone hopefully will correct me...............

In about '03 or '04 all modular heads had the plug holes modified to have approx eight threads per hole as opposed to the earlier verions with only four.

Honestly it seems this issue wasn't necessarily from a bad design but more from poor maintenance along with incorrect techniques used during plug changes. Having now owned two E250's with "early" modular motors there have been no issues. Following the recommended plug changing suggestions appears to solve or greatly reduce this problem.

 

I feel lucky then to have a 98 with the 8 threaded plug/s

 

The only 2V heads with 8 threads are on engines from the mid 2003 model and up. All early 2003 back have 4 threads in the head.

Sorry Hodges710, you have 4 thread heads.

Yes, the main issue is from either loose plugs or from them being over torqued and pulling the threads loose in the heads.

 

Sorry but it is easy to spot a 4 thread plug up to a 8 and yes mine are eight, not to mention even looking down in the bore, you can see the heads themselves or more than 4.They seem to be stock heads too. You may of got some bad info.

 

You don't have a stock '98 engine with 8 threads.

As for curing it, there have been a few on the forums that allegedly have still spit a plug with 8, too many variables to prove it wasn't operator error on an install or they really had an early '03 with 4.

The 2 piece issue is for 3V's from '04- mid '08MY and they break in half because the plug seizes in the head. I suppose your 8 thread '98 also has 2 piece 3V plugs too though.

 

nope, it uses a standard one piece plug

 

2010 F-150 5.4L

One of mine blew this morning. TSB 07-21-2 states that F-150's were only affected from 1997-2003 but it didn't help me. Just passed 99k miles and pretty sure my 5 year warranty just expired a few months ago. What a great day ...

 

I read somewhere that the issue was fixed by November 2002.

 

Not changing the plugs for 100k+ seems to be a big part of the issue.
The plugs can work loose and eventually blow one out.
My 2002 6.8L has the PI heads with 7 or 8 threads and it blew one out at 108k.
I changed plugs/boots on our 2003 5.4L at 100k and am now changing them again at 150k with no problems so far.
There are at least 5 or 6 other cases I have read about that blew out plugs with 100k+ miles on them.
At the very least check the torque at 40k or so.
I'll be changing plugs/boots every 50k and checking the torque (14ft/lbs) at 10k.

 

Both points are spot on! While I slightly disagree mileage is the main cause of blown plugs letting them go unchanged for 100K miles isn't good maintenance. I'm having a hard time believing any plug will still be as effective at 100K as it was at 50K. For that reason and that I DIY my own they're changed at 50K without fail.

Proper installation and proper torque does seem to have a huge influence over this issue so careful attention is paid there. I use nothing but Motorcraft plugs, a dab of nickel-based anti-seize on the treads as well as torquing them in at 22-23 ft/lbs. In just about 200K miles with two different E-Series 5.4 motors I've yet to have any issues at all with loose or blown out plugs.

 

I thought the same, but when I changed the plugs on the 5.4L and 6.8L at just over 100k they were running great and the plugs looked fine. I'm still going to change them at 50k. The 6.8L #3 plug was the one that blew out. I checked the torque, 14ft/lbs, on the 6.8L plugs before I removed them and all the bank 1 plugs turned a bit before the wrench clicked. Bank 2 was tight.