Spark Plug Rethread

[Nashmarauder]

Hey Guys,

New here on the site. Mentioned in my welcome post that I blew a spark plug out the engine a few weeks ago and managed to get them all tightened up after replacing the one that blew out. Got a little paranoid I was running on borrowed time, so took it into the shop the other day.

Turns out 3 of the holes have bad threading and need to be replaced with 2 other ones that might need to be done as well. Looking at $850 in repairs at minimum right now. Is that a crazy amount for reworking these holes? I know it isn't easy accessing the holes and rethreading so I'm not exactly surprised at the cost, but wondering if anybody else has experience with this?

Also, should I be concerned with the integrity of the heads with this many spark plug holes being bored into? You think I run the risk of having a cracked head? Was thinking it may have been better in the long run to just replace both heads but obviously that is going to be a much different cost.

Let me know what you guys think.

Thanks

[fastblackmerc]

Hey Guys,

New here on the site. Mentioned in my welcome post that I blew a spark plug out the engine a few weeks ago and managed to get them all tightened up after replacing the one that blew out. Got a little paranoid I was running on borrowed time, so took it into the shop the other day.

Turns out 3 of the holes have bad threading and need to be replaced with 2 other ones that might need to be done as well. Looking at $850 in repairs at minimum right now. Is that a crazy amount for reworking these holes? I know it isn't easy accessing the holes and rethreading so I'm not exactly surprised at the cost, but wondering if anybody else has experience with this?

Also, should I be concerned with the integrity of the heads with this many spark plug holes being bored into? You think I run the risk of having a cracked head? Was thinking it may have been better in the long run to just replace both heads but obviously that is going to be a much different cost.

Let me know what you guys think.

Thanks

Am I right to assume you have an '03?

03's had something like 4 threads in spark plug holes. '04's have more threads.

Your problem was most likely caused by:


Improper plug torque
Didn't use anti sieze on the plug threads
Changing the plugs with the engine hot


Just an FYI. Time-Sert is the Ford recommended repair kit.

[Spectragod]

You can buy a whole time sert kit for around $500, and it comes with the inserts, 8 or 10 iirc. Lock-n-Stith is the other Ford approved insert.


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[SteelQualityMan]

Look on Ebay if you're worried about the integrity of the heads. Huge range of prices but $1500 would get you a set of 9 thread heads.
You can buy a whole time sert kit for around $500, and it comes with the inserts, 8 or 10 iirc. Lock-n-Stith is the other Ford approved insert.


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[crownvic97]

I found a set of 9 thread heads for $750 when I was doing my build. I would just timesert the one that needs it and don’t fix what isn’t broken.

[Turbov6Bryan]

Find someone local with the tools and the actual time-sert is 15.00

850 is out of line for 5 holes

[Nashmarauder]

Am I right to assume you have an '03?

03's had something like 4 threads in spark plug holes. '04's have more threads.

Your problem was most likely caused by:


Improper plug torque
Didn't use anti sieze on the plug threads
Changing the plugs with the engine hot


Just an FYI. Time-Sert is the Ford recommended repair kit.

Thanks man. Had a ford motor certified tech go through and turns out all threads are within spec for an '03. Think the problem was the guy i brought it from must not have properly torqued all of them. Was surprised after the one spark plug blew out the engine that that hole didn't need to be rethreaded but I'll have to take ford's word for it.

[Nashmarauder]

Am I right to assume you have an '03?

03's had something like 4 threads in spark plug holes. '04's have more threads.

Your problem was most likely caused by:


Improper plug torque
Didn't use anti sieze on the plug threads
Changing the plugs with the engine hot


Just an FYI. Time-Sert is the Ford recommended repair kit.


Find someone local with the tools and the actual time-sert is 15.00

850 is out of line for 5 holes

I agree 850 seemed way too high. quote started at 6 hours of work. Turns out after all the inspections the threading was in spec for an '03 marauder so apparently I'm in good shape and was just paranoid. A ford certified tech torque everything back in and I should be good to go

[RacerX]

Thanks man. Had a ford motor certified tech go through and turns out all threads are within spec for an '03. Think the problem was the guy i brought it from must not have properly torqued all of them. Was surprised after the one spark plug blew out the engine that that hole didn't need to be rethreaded but I'll have to take ford's word for it.

It couldn't have been in all the way or just the ceramic part blew out. I've seen that before on a 351 M Cleveland, it put a dent in the hood:D

[Nashmarauder]

It couldn't have been in all the way or just the ceramic part blew out. I've seen that before on a 351 M Cleveland, it put a dent in the hood:D

Lucky for me it didn't make it past the coil pack but completely destroyed the coil pack. Rubber and coil all over the place!

[justbob]

How do you put a spec to a thread???


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[ChiTownMaraud3r]

Buy the helicoil kit, it comes with the tap tool which repaired my threads enough to make it work on the daily, without having to use the helicoil insert.

[MyBlackBeasts]

How do you put a spec to a thread???


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Isn't it amazing the bs shops/techs will tell customers... Makes me ashamed for the industry... :shake:



OP, glad you are repaired & back on the road! :burnout:

[justbob]

Isn't it amazing the bs shops/techs will tell customers... Makes me ashamed for the industry... :shake:



OP, glad you are repaired & back on the road! :burnout:



My point exactly!

It’s in spec because something can screw into it and it “looks” good on a camera?

The tiniest of midgets couldn’t find a way to crawl in with a flashlight and a thread gauge..

Kind of like the Chevy dealer I went to the other day for a window switch recall on the van. A 1 minute fix that took 45 minutes because of the mandatory 30 point safety inspection to all vehicles that come in scare tactic that they neglected to tell me about. I was livid about finding that out, more so that they claimed the rear brake pads were at 30% and the wipers needed to be replaced!!!

I then walked out and got my log book to show him rear pads and rotors replaced in late April and wiper blades were done in mid July... He was speechless and embarrassed to say the least. Idiots.


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[MyBlackBeasts]

My point exactly!

It’s in spec because something can screw into it and it “looks” good on a camera?

The tiniest of midgets couldn’t find a way to crawl in with a flashlight and a thread gauge..

Kind of like the Chevy dealer I went to the other day for a window switch recall on the van. A 1 minute fix that took 45 minutes because of the mandatory 30 point safety inspection to all vehicles that come in scare tactic that they neglected to tell me about. I was livid about finding that out, more so that they claimed the rear brake pads were at 30% and the wipers needed to be replaced!!!

I then walked out and got my log book to show him rear pads and rotors replaced in late April and wiper blades were done in mid July... He was speechless and embarrassed to say the least. Idiots.


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Yep... :shake:

[Nashmarauder]

Isn't it amazing the bs shops/techs will tell customers... Makes me ashamed for the industry... :shake:



OP, glad you are repaired & back on the road! :burnout:

Thanks brother. Your right though did feel suspicious to me when i went through all that trouble and then suddenly everything is "within spec". I'm sure you can get a camera in there to check but still...didn't realize threading had specifications till I went to the shop haha

[Nashmarauder]

Hey Folks. Reviving this thread again.

It's gotten a little colder here in Nashville this past week and have been getting misfire codes again. Car was sitting outside all day and started it at about 50 degrees and noticed the car had trouble idling and all kinds of ticking noises. Got a misfire code for cylinder 3 and a code for other misfires. This was the same cylinder/spark plug that was giving me issues from the beginning. Does the cold temps have anything to do with the aluminum heads shrinking and loosening up the spark plug? Sounds silly but i dont know anymore this issue doesn't seem to go away.

Thanks!

[justgod]

First, pull all your plugs and take a look at them, make note if any were loose. Second, how many miles on the coil packs? Do you have a custom tune in it?

[Nashmarauder]

First, pull all your plugs and take a look at them, make note if any were loose. Second, how many miles on the coil packs? Do you have a custom tune in it?

I had all the plugs tightened recently to what the dealership called "within spec" so I'd be surprised if one came loose again. Coil packs probably have 4,000-5,000 miles on them so fairly new. The car is tuned with an SCT tuner but unfortunately i do not know how to figure out what the tune has done to the car as it was done by the previous owner.

[justgod]

You can hook a laptop up through the sct tuner and datalog misfires and all sorts of parameters. Do you have a wideband?

[Chayton]

Hey Folks. Reviving this thread again.

It's gotten a little colder here in Nashville this past week and have been getting misfire codes again. Car was sitting outside all day and started it at about 50 degrees and noticed the car had trouble idling and all kinds of ticking noises. Got a misfire code for cylinder 3 and a code for other misfires. This was the same cylinder/spark plug that was giving me issues from the beginning. Does the cold temps have anything to do with the aluminum heads shrinking and loosening up the spark plug? Sounds silly but i dont know anymore this issue doesn't seem to go away.

Thanks!






"Was surprised after the one spark plug blew out the engine that that hole didn't need to be rethreaded but I'll have to take ford's word for it."


I had a feeling your fix was not going to last long. They lied to you and probably just forced the spark plug back in and called it good. You're going to need the timesert kit at the very least. I did it on my old police interceptor and it lasted for a while.