Now what do i do? (stripped thread in head)

[Dave Compson]

Let me see where do i start. I was driving home from CA to Vegas today in 120 degree weather. Heard a thump thump sound from the right front of the engine bay. Stopped the car and the engine was idling rough. I turned off the car, then back on the idle was the same. I couldnt see anything leaking or hear anything weird so i got back onto the freeway. (driving slowly) A check engine light came on and flashed for a little while then shut off. This condition of rough idle and check light going on and off continued. I was in the middle of nowhere, so i limped it home on what i thought was 7 cylinders.

I got home and thought maybe my denso plugs were in need of replacing. No big deal. My friend brought over the obd2 diaganoistic computer and found a misfire code out of #2 and 3 cyl's. I pulled the plugs off of the passenger side of the car and found the first plug (closest to the headlight on the pass side) looked good. Then i saw the rubber boot and coil of the next cyl down was completly torn up. The plug was no longer screwed into the head. The threads are stripped out of the head and there is oil covering the cylinder.

I found all of the pieces to the coil, and from what i can see, it looks like the plug backed out of the head then was smashed into the rubber boot of the coil. Also, the #3 cyl plug was loose and the threads look bad down there also.

So, i buttoned it up for the night and dont know where to go from here. Ill call reinhart tommrow to get his advise. I think i need a new head, new engine, used engine..??? Man i really need my car. Its 120 degrees here and now my ultra reliable totaly great car is reduced to a paperweight.

Help?? Opinions??

Signed--- an original marauder owner...

[Gryphonzus]

It might be possible to have the head re-tapped and have a heli-coil put in it. This might be a good temporary fix at least until a more permanant fix. The heli-coil might even be a good permanent fix if done right. But it still means taking the head off but it is cheaper than a new head.




Let me see where do i start. I was driving home from CA to Vegas today in 120 degree weather. Heard a thump thump sound from the right front of the engine bay. Stopped the car and the engine was idling rough. I turned off the car, then back on the idle was the same. I couldnt see anything leaking or hear anything weird so i got back onto the freeway. (driving slowly) A check engine light came on and flashed for a little while then shut off. This condition of rough idle and check light going on and off continued. I was in the middle of nowhere, so i limped it home on what i thought was 7 cylinders.

I got home and thought maybe my denso plugs were in need of replacing. No big deal. My friend brought over the obd2 diaganoistic computer and found a misfire code out of #2 and 3 cyl's. I pulled the plugs off of the passenger side of the car and found the first plug (closest to the headlight on the pass side) looked good. Then i saw the rubber boot and coil of the next cyl down was completly torn up. The plug was no longer screwed into the head. The threads are stripped out of the head and there is oil covering the cylinder.

I found all of the pieces to the coil, and from what i can see, it looks like the plug backed out of the head then was smashed into the rubber boot of the coil. Also, the #3 cyl plug was loose and the threads look bad down there also.

So, i buttoned it up for the night and dont know where to go from here. Ill call reinhart tommrow to get his advise. I think i need a new head, new engine, used engine..??? Man i really need my car. Its 120 degrees here and now my ultra reliable totaly great car is reduced to a paperweight.

Help?? Opinions??

Signed--- an original marauder owner...

[RF Overlord]

This issue is apparently a lot more common on the Triton 5.4, but happens on the 4.6, too. The people over on CVN swear by the "Time-sert" (www.timesert.com) for stripped plugs. According to the Time-sert web site, use kit number 5553 and insert number 51459 for the 4.6.

[RoyLPita]

Is your MM still in 3/36 wty? If so take it in. If not, do you have an extended wty? The policy would cover this repair unless the plugs were changed before. PM me to talk about one more possibility, please.

[Bradley G]

Sorry to hear of you misfortune, sounds like you have a few different options.

Good luck! and tell us how it works out!
Bradley G @ DynoPros

[Fourth Horseman]

Would it pay for us to put the torque wrench on our plugs every other oil change or so and just make sure they're all tight? Or is this not really an issue of the plugs "backing out" of their threads so much as just blasting their way out and taking the threads with them?

[Dave Compson]

First off, thank you all for the replys. I havent called anyone yet this morning to see what my options really are. To forth... it looks like my plugs just 'backed out' and werent blown out. It looks kinda like they just worked themselves loose and then took a couple of the last threads with them. The plug next to it was loose also. I pm'ed you roy, and rf... thanks ill take a look at that site.

You all know i remember somewhere the denso's were having issues like this? Anybody else out there know what the torque should be on the plugs? Or if we were supposte to use anti seize on them? Or how long the plugs are supposte to last? I put them in at 11k and not im up to 54k. The good densos i took out of the engine look fine.

Well, here i am... now what?

[jobrien8]

Torque on plug used in aluminum heads should be torqued 14-18 lb/ft. This is what we use in testing. If you don't have a wrench, snug them about 1/8 of a turn. The only times I've heard of a plug backing out (production type) is if they are not tightened at all.

[RF Overlord]

Torque on plug used in aluminum heads should be torqued 14-18 lb/ft. This is what we use in testing.The FSM says they should be 7- 15 ft-lbs... :confused:

[Dennis Reinhart]

I spoke to David there is a kit that comes in from the bottom with the piston all the way down, I would try this, before a head swap, these plugs were in the car for over 35K and unfortunately this plug apparently did not get properly tightened and loosened up and blew out, this could have happened to any plug. Hope fully the Helli coil will fix the problem.

[Dave Compson]

Thanks dennis for talking with me. I called my local dealership and the service writer i use all the time (my marauder and navigator) was nice. He recommended a new head, but before i even get the car towed to the dealership, he wants to talk to his boss to see if they can work something out. So, for today the jury is still out. Dennis, i may still be calling you for the new head. Dont really know.

Oh, i just pulled all the denso's out of the drivers side and all four looked good! So, thats nice to know. Does anybody have any certian brand or type of anti seize compund to recommend to me for my next set of plugs?

Thanks again all the replys make me feel better.

[Bradley G]

Hey Dave!,

If it is only the last couple threads that got stripped, Maybe you could Clean them up with a tap of the same size.
I would not be tickled about a few tiny specks of aluminum, getting into the engine.
If you coated the cylinder with some oil, Let it drain down,then changed the oil right after some closely observed run time.
Might be worth a shot?
Hope it works out well , whatever you try!
Bradley G

['03BlkMM]

I would try the time-sert insert 1st before paying the mega bucks its going to cost to replace the head! Here is another thread where we had talked about stripped spark plug threads!

http://www.mercurymarauder.net/forums/showthread.php?t=17086&highlight=stripped+plug

[JACook]

I would try the time-sert insert 1st before paying the mega bucks its going to cost to replace the head! Here is another thread where we had talked about stripped spark plug threads!

http://www.mercurymarauder.net/forums/showthread.php?t=17086&highlight=stripped+plug I second (third?) the TimeSert recommendation. I've done a couple of these, and I'm impressed with the engineering
that goes into these inserts. They are NOTHING like Helicoils. The repaired threads will be better than the originals,
and the repair is WAY less invasive than pulling the head.

One tip I've found useful, while tapping and cutting the relief for the TimeSert, I use a Shop Vac hooked up to blow
air into the exhaust pipe, and turn the engine until I have air blowing out of the spark plug hole, and of course, coat
the cutter and tap with grease. A second Shop Vac with a long skinny nozzle is also useful to suck all the
bits that collect on the top side of things.

Having done this on the #8 cylinder of a Triton 5.4 in an Expedition, I gotta believe the MM would be a walk in the park!

And yes, do torque your spark plugs! A good inch/pound torque wrench should be considered a must-have for
anyone changing plugs in a modular.

[David Morton]

Any small aluminum pieces in a cylinder will burn up and blow out on the first firing of the cylinder. Don't sweat the small stuff.

Loc-Tite corporation makes a good Anti-Seize compound that does wonders for steel plugs in aluminum heads. Without it, the steel and aluminum act together with any moisture to accelerate corrosion making removal hazarous as well as weakening the threads.

[Dave Compson]

Thanks everyone. Lots and lots of good ideas. Ill let you all know how it works out. I still havent heard from the dealer, maybe it will work out that way still. If not, ill do the repair (with help from friends).

[chrtra1]

Hey Dave, did you give my buddy Greg a call yet? He said he would be willing to work something out on the side if you can't get assistance from Ford.

[Dave Compson]

Chris,

Man its good to have you back here. I talked with your bro and i got the info. That was great news. I havent called him yet, because i have not heard anything from the mercury dealer yet. I was going to check back with them before calling. Hey, if they will cover even some of it, ill be happy.

[valleyman]

This thread has made me want to go out and check the torque spec on the Densos that I installed 12K ago when I got them from Dennis. This is my first engine with aluminum parts. Am I correct in thinking spark plug install/tightening is done on a COLD motor?

[SergntMac]

Am I correct in thinking spark plug install/tightening is done on a COLD motor?
Yes, you are very correct, and it could not be easier than on the Marauder.

While you spend the time and effort to check the torque, why not pull them out and take a peek? That way you'll see if...1) if your coil covers are secure and keep the elements out, and 2) if there is any tan/brown discoloring to the enamel portion of the plug. Reading spark plugs is a nifty way to stay one step ahead of the repairman.

[Dave Compson]

I called my dealer and will find out more on monday. I have a feeling they are not going to help me at all. Ill take it one day at a time. It sucks bad driving the rental impalla. I miss my car. Thanks sarge for checking in on this thread. Ill let you all know more after i talk with the dealer.

[JACook]

I called my dealer and will find out more on monday. I have a feeling they are not going to help me at all. Ill take it one day at a time. It sucks bad driving the rental impalla. I miss my car. Thanks sarge for checking in on this thread. Ill let you all know more after i talk with the dealer. If this were my engine, I would probably rather do the timesert deal rather than R&R the head. Way less invasive,
and the timesert leaves you with threads that are better than the originals. But if the dealer will handle this under
warranty, I guess they get to decide how it needs to be done.

It doesn't appear that Timesert has any distributors in the LV area, but there are a few here in Kalifornia.
I bought my set from a company called Thread Kits (http://www.threadkits.com) here in Torrance. The part number for our engines is 5553.
IIRC, the kit cost ~125.00, which isn't exactly cheap, at least not until you consider the cost of a cylinder head.
(Should it come to that...)

[Dave Compson]

Thanks so much for that post. Im still waiting for the final word. Then ill make a decision. But, ill hold onto this info and see. I really want a scope so i can see if there is any damage down there in the cyl. area.

[JACook]

Thanks so much for that post. Im still waiting for the final word. Then ill make a decision. But, ill hold onto this info and see. I really want a scope so i can see if there is any damage down there in the cyl. area.There likely isn't. This is a pretty common failure on the earlier Triton truck engines, and I've seen spark plugs
that were pretty hammered, (not to mention what happens to the coil packs) with no damage to the internals.
One easy check is to just shine a light down the spark plug hole, and rotate the engine 'till you can see the
top of the piston. Should have a nice even coating of carbon on it. If anything got down in there, you'll be able
to see from the tell-tale shiny aluminum marks.

[Dave Compson]

Well, i've made the decision to change the head. The dealer here wont help, (not suprised) so i think this my best long term option. I have placed the order for all the parts and am awaiting their arrival. Ill take lots of photos if anybody is interested. Let you all know how it turns out.

[Dennis Reinhart]

Well, i've made the decision to change the head. The dealer here wont help, (not suprised) so i think this my best long term option. I have placed the order for all the parts and am awaiting their arrival. Ill take lots of photos if anybody is interested. Let you all know how it turns out.
I would have been more than glad to get you parts at cost, I would take the engine out of the car and put it on a engine stand others may dissagree. But to me its a lot easier.

[Dave Compson]

Dennis,

You are a good friend to the membership. I would have taken you up on that offer for the parts, but i have a hook up here in town. And as for the removal of the engine. Hey, i hope we end up going that route. I would love to do my tranny upgrade, tc and cooling mod that i've been sitting on for over a year! Well, ill write back more after we tear down the engine.

[Dave Compson]

Here are the photos of todays carnage.

http://www.mercurymarauder.net/gallery/showgallery.php?cat=500&ppuser=182

If that dosent work, just check ot my photos in the gallery.

Today, we took apart the engine and removed the head. Now its time to clean up and wait for the parts. When you look at the photos, check out what happened to my coil and plug.

Let me know what you all think.

[BruteForce]

Was the damage to the coil from taking it off?

[Dave Compson]

The damage to the coil was from the plug being pushed out of the head and banging into the coil and head after it was set free. There is thread damage to the head, but it looks fixable. Hope that answers your question. It looks like the end of the week for parts to arrive, then ill see what time the mechanic has to do it.

[JACook]

The damage to the coil was from the plug being pushed out of the head and banging into the coil and head after it was set free. There is thread damage to the head, but it looks fixable. Hope that answers your question. It looks like the end of the week for parts to arrive, then ill see what time the mechanic has to do it. The coil damage is exactly what I've seen on the Tritons I've worked on with this problem.
If you don't mind, I'm wondering why you decided to go this route instead of the TimeSerts?

[Dave Compson]

Im replacing the head completly. Its expensive, but i like the peace of mind. I just dont trust the thread fixes.

The one thing i have learned from all of this... check your plug torque! I plan on doing it now every 10k miles. Now, im paranoid.

[RoyLPita]

Any thoughts on adding a s/c while you are in there?

[JACook]

Im replacing the head completly. Its expensive, but i like the peace of mind. I just dont trust the thread fixes. Fair enough. I never thought much of "thread fixes" either, as a group. Too many bad memories from my
early youth spent wrenching on Volkswagens. Those inserts seemed like a good idea, but they were poorly
executed. They would usually come out with the spark plug, taking even more bits of cylinder head with
them. They also slightly relocated the plug higher in it's bore.

Likewise I'd never put a Helicoil in a spark plug hole. If you were lucky, those would come out with the
plug. If you were unlucky, they would go in when you reinstalled the plug. Or partially in, so's you
wouldn't know it had happened, but there'd be this tail sticking into the combustion chamber waiting to
glow or come off. Also, with Helicoils, you have to change to a gasket-seat spark plug, or you'll end up
with combustion gas leaking past the threads.

But, I would not lump TimeSerts in with these. Their one-piece stainless insert is mechanically locked
into place after installation, so it can not come out. It also perfectly replicates the factory threads
and tapered plug seat, exactly where the factory put it. The repaired plug seat is actually better than
original. Enough so, that several respected engine builders are using TimeSerts in every spark plug
hole, on every Triton cylinder head they install. The Caddy Northstar guys swear by 'em for repairing
that engine's fragile head bolt holes. Likewise many Porsche shops do TimeSerts in all the head
stud holes as a matter of course.

It's also worth mentioning that, if you had this problem on a General Motors product, and it was under
warranty, there's a pretty good chance they would have done a TimeSert repair. GM dealer mechanics
have been using TimeSerts since at least 2000. This GM TechLink (http://www.gmtechlink.com/images/issues/arcv_pdf/1_00_e.pdf) document gives some additional info.

Unfortunately, if you ask most general mechanics about doing inserts, all's they know about are those
VW inserts and Helicoils. So it's understandable they don't like the idea of an insert. But I have yet to
hear of a mechanic that has used TimeSerts and has something bad to say about 'em. For me, the only
question would be whether to do them on-car, or pull the head.

Just sayin'...

[Dave Compson]

Sorry, cant afford to do a s/c install right now. I am adding a php intake spacer though. (just ordered today from dr) That is the only mod i'm doing now.

As for the insert, that probably would have worked well. I just need to know for sure the head will hold. The car is paid off and i have no plans for selling it. So, for the long haul, the best fix is just a new head and a little time spent checking the plugs.

Its really hot here now, but i need to get out in the garage and clean up the mating surfaces. (so im ready for the new parts) Hope the parts arrive soon, and the mechanic can come back and install. The engine looks good inside, really clean and no damage. So, dennis (and others) were right.

So, does anybody want a used head? Do i make it a paperweight or fix it and sell it to someone? Maybe ebay? dunno...

[Dave Compson]

Horraay!! Well, the girl is finally back on the road! Today, my new friend (mechanic greg) and I installed the new head and related parts. Actially it was not that hard. I am so happy the car is up and running again! I cant begin to explain how good i feel. I didnt get to install my new php intake spacer, it has not arrived yet. So, ill get to that later. I didnt bother to take photos, but the engine is the cleanest part of the car now. It runs great, and i cant tell anything has changed from before. It runs great and next weekend ill change the oil and filter again for good measure. So, thanks all for being there for me. The engine looked nice and clean, so it was easy to work on. It pays to keep the car clean and in order. Also, the most important thing i learned from this. Check the torque on your plugs every 10k miles.

Dave

[valleyman]

Im replacing the head completly. Its expensive, but i like the peace of mind. I just dont trust the thread fixes.

The one thing i have learned from all of this... check your plug torque! I plan on doing it now every 10k miles. Now, im paranoid.


Just as a follow up .... I checked all eight of my Densos today and all were tight. I didn't realize how long they'd been in there, I've got 30k on the car and they went in at 12k. All of them are the same color, a light gray with just a hint of tan (gawd that sounds gay!) including the one closest to the firewall on the driver's side. My car has the DR head cooling mod on it and sees 5k rpm every day. When I installed the plugs I used a very little bit of Never-seize and torqued to 15Nm. They came right out with no trouble. :bandit:

[Dave Compson]

Thanks so much for posting. When i removed my densos, they all looked uniform and good for many more miles. Prior to returning my orig. head to the dealer for the core charge, i fully inspected it. I discovered the plug that came out had completly destroyed all of the threads, this is different from before where i thought it only took out the top couple after working its way loose. After checking out the head, the only conclusion is that;

Extreme heat (130 degrees in death valley that day) had something to do with the failure.

Improper torque specs when installed, (i installed them at 11k and the failure was at 54k)

Lack of anti seize. (dont remember being told to use it)

But, the bottom line is now everything is great, and back to normal. I will check my plugs more often as a precaution and for peace of mind.

Thanks all for your support.

[merc]

Improper torque specs when installed, (i installed them at 11k and the failure was at 54k)


What is the proper torque spec Dave ?

[valleyman]

What is the proper torque spec Dave ?

Shop manual calls for 15 Nm/11 lb-ft.

[Dave Compson]

Yup, that sounds right.

[magindat]

Is it possible the factory did not use (or used an insufficient amount of) anti-seize? I know galvanic action (electrolysis) will "eat up" the weaker metal. Could the threads have simply weakened or degraded entirely due to contact with steel and high voltage? Don't forget, the spark sparks because the plug is grounded by the same threads that were eroded.

Speaking of galvanic action and anti-seize... I got my MM from a guy's estate. He had been ill for some time, then died. Long story short the car sat for about a year and a half or more. The lug nuts seized to the wheels. It took 2 guys and a 4ft break bar to free them. I'm really surprized the studs didn't break.

After this post and my wheel experience, I think I'll get the plugs changed at the dealer and remind them to smear on the anti-seize!!!!

[RoyLPita]

Horraay!! Well, the girl is finally back on the road! Today, my new friend (mechanic greg) and I installed the new head and related parts. Actially it was not that hard. I am so happy the car is up and running again! I cant begin to explain how good i feel. I didnt get to install my new php intake spacer, it has not arrived yet. So, ill get to that later. I didnt bother to take photos, but the engine is the cleanest part of the car now. It runs great, and i cant tell anything has changed from before. It runs great and next weekend ill change the oil and filter again for good measure. So, thanks all for being there for me. The engine looked nice and clean, so it was easy to work on. It pays to keep the car clean and in order. Also, the most important thing i learned from this. Check the torque on your plugs every 10k miles.

Dave

I found this in Ford's Special Service Messages:
18310 1995-2005 MULTIPLE VEHICLES - REPAIR PROCEDURE FOR STRIPPED OR MISSING SPARK PLUG PORT THREADS
DO NOT SERVICE STRIPPED OR MISSING SPARK PLUG PORT THREADS USING ANY TYPE OF THREAD REPAIR KITS (E.G. HELICOIL). IT IS LIKELY THAT ENGINE FAILURE WILL OCCUR BECAUSE THE HEAT TRANSFER FUNCTION BETWEEN THE SPARK PLUG AND CYLINDER HEAD WILL BE AFFECTED, CAUSING PRE-IGNITION. TO SERVICE STRIPPED OR MISSING SPARK PLUG PORT THREADS, REPLACE THE CYLINDER HEAD. REFER TO WORKSHOP MANUAL SECTION 303-01 FOR CYLINDER HEAD REPLACEMENT PROCEDURE AS NEEDED.
EFFECTIVE DATE: 11/23/2004

Just thought to share this with "younz"<--(Y'all in Pittsburghese).

[Dave Compson]

Well then... happy i did the correct fix. The car runs great now. Im not worried about having one new head and one older one.