Dog Folks wrote:
I do not a vehicle with spark plugs and I am a gear head of the 60's.
Can someone explain, briefly, why these plugs are such as issue? Corrosion? Access? Is this just Ford issue? What engine sizes does it affect?
In my day boys,(Yes, here it comes: another old timer story) it was not unusual for us gear heads to change plugs on a V-8 in 1/2 hour and do it every 15,000 miles. Of course, I understand that back then the engines had to have fresh plugs due to inefficiency of combustion when compared to modern engines.
It is a combination of issues.
Due to the 3 valve arrangement there is little room for a "normal" plug like you would have used in the '60s-'90s..
A 3V Ford plug looks like
Mostly the Ford 3V "modular" series are affected (4.6, 5.4 and 6.8 V10).
The valve configuration forced the design to have a deep plug "well" of about 4" and the plug has a long reach tip. Add in mixing aluminum heads and steel spark plug plus the long reach tip and an early 3V plug which was made of two steel pieces and you have the "perfect storm" so to speak..
While the 3V Modular engine does have this issue it isn't really all that big of a problem IF you take your time and have the proper tools..
Overall the 3V mod engines are really robust and have a very long life..
