Stripped Spark plug Hole 3.8L gen 3 Limited

[LetsMontero]

Welp... This is not how I wanted to introduce myself to this forum but... here I am. Just bought what I thought was an extremely good condition 2003 Limited. 134K miles no rust vehicle that had the valve covers leaking along with a few other odds and ends that I could handle. while I was changing the valve covers, did the plug seals, rear cam seal, went to change the plugs they all came out nice and easy and back in nice and easy except one. #2... Thought it just wasn't "catching" so went and got a thread chaser... Turns out there was nothing to catch! Plug was bottomed out in the hole... Anyhow long story short has anyone installed an insert with any luck? Or am I into swapping out the head? I'm in Virginia Beach. Planned on wreching on this as my little hobbie truck but thought I'd get some fun out of it first! Also are there any other vehicles where the head would be the same to swap if I needed it? Thanks all!

 

[nwoods]

I've not done an insert on a Mitsubishi (Chrysler) head, but I have done it on a Jeep 4.7L aluminum head and a Ford 5.4L 2-valve aluminum head. It works, and its not terribly hard to do. Fords have a habit of blowing spark plugs completely out of the head. Something about the number of threads being too few to properly engage with the plugs? There is a kit for them that provides a longer thread shank basically just a bit helicoil insert. On my Jeep, I just used a standard helicoil kit. It worked. I would assume the same for your chyrsler motor.

 

[LetsMontero]

I've not done an insert on a Mitsubishi (Chrysler) head, but I have done it on a Jeep 4.7L aluminum head and a Ford 5.4L 2-valve aluminum head. It works, and its not terribly hard to do. Fords have a habit of blowing spark plugs completely out of the head. Something about the number of threads being too few to properly engage with the plugs? There is a kit for them that provides a longer thread shank basically just a bit helicoil insert. On my Jeep, I just used a standard helicoil kit. It worked. I would assume the same for your chyrsler motor.

Am I right in stating that the head on the 3.8 is not aluminum?

 

[nwoods]

Am I right in stating that the head on the 3.8 is not aluminum?

Oh, it totally is alum. I have pictures of my tear down of my 2002 Montero engine a few years ago. https://nwoods.smugmug.com/Vehicles/Montero/3rd-Monty-Restoration

 

[LetsMontero]

Oh, it totally is alum. I have pictures of my tear down of my 2002 Montero engine a few years ago. https://nwoods.smugmug.com/Vehicles/Montero/3rd-Monty-Restoration

Thats the 3.5 in the 2002, I have the 3.8 in the 2003, does that make a difference? Also thank you for responding!

 

[LetsMontero]

Well I cut new threads and install the insert to torque spec so... Should be good to go!

 

[Michael Brown]

That's about the best you can hope for without removing the head. Good luck with the repair!

I know that issue with the Ford 5.4 Triton also extended to the V10 as well.
It started as failing threads that would fire the spark plug through the coil into the hood.
Their "fix" added more material to the location so spark plugs then got stuck and would break.
There are specific tools now for removing broken spark plugs from Triton motors.