Manager Forum

We put put new head gaskets on a 03 Explorer with a 4.0 flex fuel. Truck was severely overheated, heads were warped 18,000. Installed all new timing components. When we started truck up it ran great for about 3 minutes and then we heard a rattling noise it started to run rough and now will not start. We have fuel and spark.

First thing I am wondering is: What is compression? That is where I'd start if that were in my shop.

If i were a betting man i would bet you threw the chain. As a rule, in my shop, i would have R&R'd it. An overheat that bad would have possibly tempered the block and trashed the rings. I've seen bolt holes that even though the bolt threads in it will not seat and grip. If the head wasn't planed properly with the cam there is a possibility it snapped or spun. May i suggest, and i've had to do it, install a used engine and get this behind you. Tough one to eat but if it were me i would understand this will hang over my head like the Sword Of Damiclies. I would end up spending way more time on it than it was worth. One time i purchased a vehicle after it imploded while i worked on it just to make it go away.

Well, I am also thinking it is a chain issue, although a compression check would steer you in the proper direction.

Yea, these engines are touchy ones, not my favorite one to be working on.

Put a good used motor in it. This thing had overheated so many times it melted the oil pump screen. Thanks for all the input.