Came out of work, go to start it up, and it just sounded wierd, and wouldnt start at all. The rhythm of it was just a bit off, like the timing chain had jumped or something. Turns out it wasnt the timing chain, cyl #6 has no compression, checked it twice, couldnt believe it. It has been a decent engine, but I wouldnt buy another. Anybody want a decent 98 F150? sell it cheap.

 

Eh... apparently you weren't informed about the 97-98 4.2l V6 engine Hydrolock problem.

Once fixed, the engine will last 300k easy with regular maintainance.

 

How much is "cheap"

Manual or auto?.... rear end gears?

 

is it a 4x4 and what's cheap?

 

er, it wasn't hyrdro-lock. I don't know what it was, but the build date was after the supposed "fixed" gaskets, not to mention I had replaced them just in case anyway. As far as cheap goes, I really dont have a price in mind yet, I dont know what it would even be worth. My wife is trying to talk me into replacing the engine and keeping the truck. I dont like that idea, I dont really enjoy working on newer cars, everything is such a pain to get to plus I am in the middle of a Mustang restoration and would much rather work on it.
1998 4.2, 5 sp, 2wd, 3.55 rear, 143,000, sport appearance package (no sport stickers though), gray int, no frills, body isnt perfect, but still looks pretty decent.

 

2nd update, just for the heck of it, I pulled off the valve cover, intake valve is stuck wide open, which means something is holding it open or it is severely bent. Hopefully there is no damage to the cylinder and this wont be as bad as I thought.

 

Intake valve was bent, you can see where the piston hit. Luckily no piston damage. It was stuck in the guide, was a real pain to get out, but once I got it out and sprayed a little lubricant in the guide it moved freely enough. There is a small gouge in the valve stem near the top, I cant tell if something may have gotten in there and cause the valve to stick or it is just coincidence. I really dont know what happened or why. Sometime between shutting it off when I got to work and starting it to go home this happened. If it was a hydrolock problem you would think it would have happened when I started it to go to work, after all I didnt drive it all weekend, and that shouldnt have bent the valve anyway. I will be putting it all back together this weekend and hopefully it was just a fluke thing that wont happen again. On a side note, after 143,000 miles there is almost no carbon on the the pistons, valves etc. I am amazed at how clean the internals are.

 

I would advise you to check that pushrod carefully too.

 

Glad to hear it's not looking too bad for you. I've had two F-150's both with the 4.2L and these engines really seem to be bullet proof. Rarely do I even see negative posts about them, well besides the typical issues which are usually easy fixes and them being slow. Good luck with it.

 

Definitely strong little engines. These things can make all sorts of noise, throw thirty SES codes and keep on chugging.

 

Any chance the cause of the bent valve was over rev ving the motor?

Possible valve float at high rpm, allowing the piston to kiss the valve just enough to bend to valve.

Maybe a weak valve spring allowed the valve to get out of control?

Sorry to hear about the problem - just throwing out ideas of what might have been the root cause.

 

Hard to say, except I am pretty sure it is not over-revving that caused it. I dont really run it out like its a real high revving hot rod, cause it isnt. I do get on it, but I dont take it to the limit. One thing I know for sure is that as long as I am working on my truck, my Mustang is being neglected, and that is driving me nuts.

 

You can't overrev the engine - the limiter will kick in.

 

Was there a lot of carbon build up in the chamber?

 

I know you can over-rev them with a standard. I did it to my '99 a few times. Boy, it didn't like that...