Have you guys ever heard of a spark plug being blown out of a head?

Discussion in 'SN95 4.6L Mustang Tech' started by jayssilver4.6, Jan 10, 2006.


  1. mrvax

    mrvax Stay thirsty my friends Founding Member

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    The problem is there are not enough threads in the head. I had 1 blow out on me about 2 weeks after I swapped my plugs. Thank God it did not take out the threads. When I install plugs, I make sure not to over tighten them. I must have had 1 a bit too loose.
     
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  2. Cantslowdown

    Cantslowdown New Member

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    So I take it ford is trying to use the the extra threads on the new plug to keep them in..
     
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  3. bdcardinal

    bdcardinal tree hugger

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    theres enough room. you dont have to pull the fuel rail. the boot is rubber and will bend a lot. i use a spark plug socket thats about 12" long with a universal joint.
     
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  4. Mike97gt

    Mike97gt it doe snot Mod Dude Founding Member

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    after it has blown one out yes it's loud as hell and has no power. but when they loosen up a bit and are still in they tick. did'nt we just go over this
     
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  5. Cantslowdown

    Cantslowdown New Member

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    Yes but i have changed my plugs and the motor sounds the same but runs alot better.. The plugs i took out had a short thread area.. The new ones have a nice long thread area.. But still sounds the same just runs alot better.. All plugs looked the same nice and clean no oil just the normal old color all kinda light gray..
     
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  6. Mike97gt

    Mike97gt it doe snot Mod Dude Founding Member

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    atleast now you know it's not your plugs :) check them every other oil change.
     
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  7. Cantslowdown

    Cantslowdown New Member

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    Yes thats very true... She isnt getting hardly any miles on her cuz of this weather..
     
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  8. QDRHRSE

    QDRHRSE New Member

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    This is really common with Lightnings. There are a few good fixes. If you have the heads off you can have the sparkplug holes sleeved with a steel insert. If the head is on the car still, they have these things called Time Serts. I've heard a lot about them although I don't know exactly what they are- this is a great fix I hear. Its like $300-$400 a hole and it gets cheaper if you have more than one. As far as aluminum getting into the motor from heilicoiling- the cylinder is steel so the shavings won't do a thing. However, If a valve opens and closes on a chunk of aluminum over and over, you could damage a valve, but even that is unlikely as the valves are also steel. I'm not sure about the valve seats but they are probably steel too.

    Sorry...had to edit. I didn't even realize that you guys already talked about the time serts. Sorry. My bad.

    +1 for time serts
     
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  9. CJK44t

    CJK44t New Member

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    Its not the plugs, its the heads. New plugs will not help. There is only 3 engagement threads in the alum head.

    More threads on the plug are meaningless if they have no threads in the head to grab onto. The extra threads just sit in open space.

    This is something that bothered me alot when I had my 5.4L F-150. Not that I couldn't handle the repair, its that 4 of the plugs are under the windshield. At least I can easily get to them on my mustang.

    The repair kit is from Timesert as was mentioned. They have 2 kits. One has an insert that fixes the plug hole right back to the same design but in steel.

    The other replaces the old design with a typical fully threaded spark plug hole, but you MUST use fully threaded plugs now.

    http://www.timesert.com/html/ford_sparkplug_faq.html

    I would not hesitate to do the on-motor repair using grease to capture most of the shavings. The small shavings that happen to enter the combustion chamber will not likely cause a problem. They are soft and small and will probably burn up inside.
     
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  10. Kilgore Trout

    Kilgore Trout Fried or Broiled ?

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    That is pathetic :nonono:
     
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  11. QDRHRSE

    QDRHRSE New Member

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    This is an old post.
     
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  12. CJK44t

    CJK44t New Member

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    Yup, I got the link in the FAQ and figured I'd update it with a timesert link. Somehow I doubt the spark plug blowout thing was a passing trend. :D
     
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  13. jcode68

    jcode68 Active Member

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    Definately not a passing trend. I appreciate the update with the Time Sert link. I blew my #3 plug out last week. Towed to the dealer, they said $3500 to replace the head, Ford won't allow helecoil yadayadayada. Found this thread (Stangnet rules!) and the info on Tim Serts. Their tool kit was super easy to use, excellent instructions and took about an hour to repair and didn't have to pull the head. Anyone out there with this problem, don't waste your money replacing the head and don't let the dealer tell you that the head needs to come off just so they can charge $1500 in labor. Car is back on the road and runs as good as old. If anyone is interested in buying my Time Sert tool kit, PM me. The kit comes with 5 inserts, so there are 4 left.
     
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  14. Mike97gt

    Mike97gt it doe snot Mod Dude Founding Member

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    I see your in massachusetts.. What dealer did you go to?

    many times the reason the dealer wants to replace the head is because we have had some insert repairs fail, it's not often but it can happen and some dealers do not want to risk replacing the head for free.
     
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  15. 1low03gt

    1low03gt Member

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    I've noticed that mine came loose a few times on a cpule of plugs.So now i make it a habit to check them once a month as i don't drive her a lot.If i drove her everyday,i would probably check them every second week.Better safe then sorry :shrug: .
     
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  16. 8950HO

    8950HO New Member

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  17. jcode68

    jcode68 Active Member

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    I had it towed to the closest one where I work, Stoneham Ford. I could see your point if my car were under warranty, but it is not. In my opinion, Ford should provide dealers with an acceptable solution other than head replacement for out of warranty customers. The distributor I bought the Time Sert tool from is in Tyngsboro, MA and he said he can't keep these things in stock, sold 12 last week alone. So this is obviously a big problem and Ford should step up on some level. I also think a portion of this is up to the dealer in the way they handle it. They charged me $50 to "diagnose" the problem and presented the "only" solution was head replacement. I'm sure any mechanic (especially Ford certified) would have taken all of 30 seconds to diagnose the problem, it was very obvious once I knew what it was. I was happy to pay it since at least I knew for sure what the problem was, but it still burns my a$$ because I know there was no real effort involved. Rant over, car is fixed :D
     
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  18. RED2001GT

    RED2001GT New Member

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    I found this thread after the cheif mechanic at Ford service told me that the spark plugs on a 2001 Mustang GT need to be replaced every 5 years/50,000 miles, whichever comes first and that they would get stuck inside the heads and/or possibly break if they were not replaced at the proper mileage.

    The reason why I am bringing this particular thread up is because my 2001 Mustang GT has ONLY 2,6xx original miles on it. I purchased the car brand new back in August 2001 and have only driven it an average of only 500 miles per year every since I've owned it.

    Anyways, a red flag went up when the mechanic told me that the spark plugs on a 4.6 liter Mustang GT motor can get stuck inside the heads and possibly break if they are not replaced every 5 years/50,000 miles. When he told me this, I did a search and I found this thread. Could the mechanic made a mistake when he mentioned to me about the spark plugs getting stuck inside the heads and possible break if they are not replaced with brand new ones every 5 years/50,000 miles? He said that when they get stuck that they can break inside the heads and that the only way to repair this would be to replace the heads. Is this true? How easy is it for the spark plugs to get stuck and break inside the head when spark plug replacement time comes? Yhe mechanic never mentioned to me anything about the spark plugs blowing out of their threads from inside the head.

    Would my 01 GT be a good candidate for the spark plugs to blow out of the heads if I have only put less than 2,700 miles on my car within the last 5 years? Is there any truth in what he said to me about the spark plugs breaking and getting stuck in the heads if they are not replaced at the proper mileage?

    Also, is it safe for me to currently still drive my 01 GT with the original spark plugs still inside the heads with less than 2,700 miles on the engine if I only put less than 1,000 miles more on the engine before I store the car for the winter? The mechanic told me that it will be currently okay for me to drive my 01 GT until I store it later on next month in the end of November and that he wants me to bring it back to him in the spring time again for him to do a full spark plug and wire change on it before I put it back on the road next year in 2007. He said that if I don't change the spark plugs that they will get stuck inside the heads and not come out and that they might break inside the heads causing me to need new heads. Is he right about this? If he is right, what would cause the spark plugs to get stuck inside the heads and break?
     
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  19. Pearl02

    Pearl02 Member

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    I've never had a spark plug get seized up in a head before. I'm no Ford tech but I don't buy into any of that. I'm sure there are reasons for a plug to get stuck in a head. The problem with Ford modular motors seem to spark plugs staying in the heads. I wouldn't worry about that if i was you. Drive your car and enjoy it. With only 2700 miles I would be concerned with other problems(engine sludge,moisture in brake fluid,dry rot and cupping of tires to name a few). Pearl02.
     
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  20. speedytang

    speedytang Founding Member

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    The truth is both are a problem. The anti-seize Ford used burns off over time and the plugs which are steel into a aluminum head causes the plugs to become WELDED into the head. The next problem is the plugs blow out because when removing the old plugs some of the thread came out with the plug and does not allow enough surface for the new plug to stay in. Helicoil is what I have had to do for people to keep original plug size or tap the heads out with a special tap that Ford sells to go up to a oversize plug that is made just for this application.
     
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