Looking For Leakers In Ford's Duratec 3.0L Engines

Ford Duratec engines manufactured for the 1999 model year vehicle applications may have a greater tendency to leak. If you have ever experienced the joy of doing a plumbing project you learn very quickly about how the proper amount of heat in the right place will literally leach the solder into the joint to seal the copper pipe properly – or not. It becomes obvious where you failed to do so once you open the main water valve and you suddenly realize you have a leak.
That is exactly what can happen with the 3.0L DOHC Duratec Ford engines. In particular, those engines manufactured for the 1999 model year vehicle applications may have a greater tendency to leak.
It seems that engines built prior to 6/15/1999 used one head gasket and cylinder head/block combination and after that date used another (Additional casting numbers and details can be found by searching “Ford 3.0L Duratec”.
There are three different areas which clearly identify which head gasket is which and a small change was made to the coolant port area between cylinders No. 2 and No. 4 on the right bank.
If the wrong style head gasket is used you will have a coolant leak to the exterior of the engine, which on initial start up changes your shoulder posture from bold and robust to hunched over and distraught, usually with a small moan connected to it. So before that happens, understand this important fact: if you have an F5 or F7 block use the early gasket; if it is an XW block use the later gasket.
If you look at Figure 1 (above) you can see why. First compare the head gaskets early and late, noticing the three different color boxes on both gaskets. The picture shows the early view on the top and late view on the bottom. There are also minor differences in the head castings.

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