OK, My mind is stuck on Excursion.

 

Can you tell me what is the proper spark plug for replacement of these two piece plugs that break? Are there any one piece plugs that won't cause this problem again?

 

The latest plugs from ford are a 2 piece design originally 3 piece. The newest plugs are SP-515 from Motorcraft and according to Ford they shouldn't have this same problem in the future.

 

Are the 3v 6.8's easier to change the plugs on?
Is there any advantage to running a couple of cans of seafoam in the last tank of gas before attempting plug removal?

 

There may be, problem is the carbon is so far up the tip. I have done a full induction service with our BG chemical machine here at work on a few of them and no real difference still broke a few. The 5.4l is the worst one where as the 4.6 and 6.8 3v have been allot easier it seems.

 

Why is the 5.4L the most problematic one out of the modular engines for this?

 

The reason being is the 5.4l was the first 3v engine of this design and plug. Therefore most mistakes were learned and corrected before they engineered the 4.6 and 6.8 3v version as they came out about 2 years later

 

I think a heavy dose of Seafoam, Marvel Mystery Oil, etc, in the gas tank would greatly help the removal. I am thinking like a gallon of it in a quarter tank and get those RPM's up there to blow that junk out, then use the carb cleaner and let it sit in the holes overnight.

 

I don't want to melt the pistons just free the plugs.
Have had many experiences melting pistons by running alcohol in two stroke sleds.

 

But they make great ashtrays.........

 

This ain't a 2 cycle and who said alcohol?

 

Seafoam is not an ethanol based product, its a petroleum base. Unless your going to use straight ether (starting fluid) you will not melt your pistons running seafom. But Buying a gallon of seafoam will set you back about $60.

 

They have gallons of Marvel oil at Walmart (pretty cheap) and how much would half a set of broken off plugs cost? Not to mention dropping part of them into a cylinder or two.

 

On topic but kind of a hijack...........My 08 5.4 has an engine build date of 2-14-08. From what I can gather, I think thats late enough for the sorta Ford fix on the 3 piece plugs? Or am I looking at the same problems?

 

Pull a coil if you have brown boots your are gold!