97 ford expedition - 4.6L W engine - 4X4 -- cylinder #2 stripped?

Question

My #2 cylinder (passenger side second from front) on my 4.6L W type engine -- 4X4 -- spark plug stripped the aluminum block.

Tried to get heli coil installed unsuccessfully -- since plugs are recessed so far down inside cylinder head.

Instead in order to get it back on the road, they "glued" the spark plug into the head -- and in the process got some glue on the tip of the plug (I'm guessing) based on the continually deteriorating performance. Body is in great condition.

I'm currently on the second engine -- first one blew at 99K miles and it was replaced with a 25K mile replacement (warranty work from Ford's extended warranty thank goodness). It now has about 175K miles on it -- so this engine has roughly 100K if I'm ciphering correctly.

Should I replace the cylinder head or entire engine -- in other words do I have to take the engine out to change the head?

Any advice would be appreciated -- and NOOOOOO getting rid of it cuz it's a ford is not what I had in mind :o)

Answer 1

Repair the spark plug threads and not with a helicoil. Helicoils are great for bolts. I got a kit from pepboys. you can probably get it anywhere. It may have been made by helicoil but it was not the traditional spiral wire inserts, these were metal sleeves that had knurls on the outside threads. It comes with a special tap to clean out the old hole. thread the sleeve into the hole and whack the set tool with ahammer to set the sleeve. I would put a few drops of thread lock onto the outside of the sleeve so it locks to the head and doesnt come out nexttime you change plugs. The kit came with 3 differen tlength sleeves to fit different plugs. I used all 3 on different cars and they worked great. It even works when you have no threads left in the head because the sleeve takes up that space. dont wory about aluminum chips, they are too soft to cause damage and they blow out the exhaust

Answer 2

there are heli-coils you can get for that motor.. I've done them but aren't recommended as they can blow out of the head but facing the head bill, pople rather take a chance.

I'm surprised the first blew when it did, most go for a long time..

But anyhow, the motor is a good motor and changing the head will work and not cause any problems, but in a mechanic shop, we found that by the time you get the head figure in the extras needed to replace etc. etc.. throw in about a grand more and get a reman engine with a warranty from Ford (now 3/36) or from jasper (3/75)

Answer 3

Just a theory here, but if you stripped the plug, chances are you have some metal shavings in that cylider, which could cause scratched cylider walls and damaged piston rings...etc, effectively killing that cylinder until it is bored out during a rebuild...
A junk yard motor is a safer bet than replacing just the head, and is also about the same as far as labor is concerned. Dont have the dealer do it...unless you are made of $$$.

Good luck

Answer 4

You get a tool to re tap the hole, but you have to weld a square rod by a welder so it would be long and straight, then re-thread the hole, put a coil in, hit it, then put the plug tight.
Otherwise you have to change the cylinder head. You don't have to take the engine out to remove the head, but it is a lot of work.

Answer 5

Aluminum eh..when you put a hard metal object (steel spark plug) in a softer metal (Aluminum) and don't get the thing threaded in right and FORCE it that is what happens. They USED to make a sleeve that you screwed into the drilled out and taped hole, keep the sleeve in with some JB Weld, then you put the plug back in..dunno if they still make those, or if they do where to get one, good luck looking. Nye

Answer 6

changing the head with ford dealers would be a good choice.
i dont know whether if they provide cylider head alone......
nyways jus giv it a try,,,,,,,
if you try to repair and use the same head, there might be certain performance lags unless you've got a great mechanic.

Answer 7

ford dealers will remove the engine to do the head but you dont have to but with the timing chains and all i'd recommend that you dont try it yourself good luck

Answer 8

You can remove and install the head in the truck and that is what I would do. It would be the best bet and money saver.

Answer 9

you can remove the head and replace it, but with all those miles on it, you will increase the compression and you might start burning oil, i would recommend getting it rebuilt or exhange.

Answer 10

Yep.....when nothing else to do I start around page 6 and work backwards.