Trouble shooting a no start again...

Discussion in '2005+ Mustang GT 4.6L Tech' started by xkillerxnatedog, Oct 28, 2019.

  1. RLF9409

    RLF9409 My blood runs Ford blue!

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    Piston is not going to ever make contact with a spark plug.
    Now you might have bits of a valve that would cause damage but you would have heard it knocking around. And I don't think loss of compression is going to flood the other cylinders with oil...

    Anyways, you lost a piston...that sucks. If money is tight...You may want to research a junkyard motor. Most come with a warranty. Otherwise your taking a risk on a partially rebuilt motor. If you keep your motor you can build it into a monster.

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  2. xkillerxnatedog

    xkillerxnatedog Member

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    That's pretty much what im thinking on doing if i gotta tear the motor apart aslo he said, He would know more once the valve cover an head come off to see exactly what happened.. What all should i replace since most likely piston number 8 is gonna need replaced.. Would like to set the car up for boost eventually... Maybe go with some forged internals any good sites to look up for these parts?
     
  3. RLF9409

    RLF9409 My blood runs Ford blue!

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    Depending on what the actual problem is but You should rebuild the entire motor. These are high performance motors. You can't just do one cylinder.

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  4. Dino Dino Bambino

    Dino Dino Bambino I have a red car

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    My guess is that you dropped a valve in the no.8 cylinder and the piston smashed it with the valve fragments taking out the spark plug electrode as well. The only way to find out for sure is to pull the driver's side cylinder head. The head itself is probably also damaged, and you may find fragments of piston and valve sitting in the oil pan. Just hope that the no.8 cylinder wall isn't severely scored so that you can reuse the block. If the engine's completely trashed and needs to be replaced, this would open up other possibilities depending on your budget.
     
  5. xkillerxnatedog

    xkillerxnatedog Member

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    Well when i changed the oil i didn't see any metal shavings or fragments in the oil so idk... Well keep you guys informed when i get the ball rolling
     
  6. xkillerxnatedog

    xkillerxnatedog Member

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    I got a quick question for you guys is a 2011 crown vic 4.6 l 2v compatable with my 06 3v Mustang thinking about doing a swap but would like to use my cams longtube headers from my 3v an put them on the 2v?
     
  7. Pentalab

    Pentalab forum member

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    If a valve spring broke, the piston would smack the valve, not the plug. But the head for cyl 5-8, on driver's side needs to be removed. This is the 1st time I have heard of a valve spring breaking.

    Perhaps 1st remove the valve cover off the driver's side.. then inspect the 3 valve springs and 3 valves for cyl 8.
     
    Last edited: Nov 12, 2019
  8. xkillerxnatedog

    xkillerxnatedog Member

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    Well what would have caused the plug to be smashed then... I figured it was from a dropped valve that came up an smashed the plug from the piston... Maybe if it warms up next couple days il pull the drivers side valve cover an inspect the springs an valves
     
  9. 07gts197

    07gts197 forum member

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    No do not use a 2v. Get another 3v out of a mustang. A few other models used the 4.6 3v as well but there are some differences.


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  10. 07 Boss

    07 Boss Senior Member

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    Uhhhhh........ how are you going to run a cam made for 24 valves on a motor with 16 valves? Lol.
     
  11. xkillerxnatedog

    xkillerxnatedog Member

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    Lol i was just asking i wasn't sure about the 2v compared to the 3v but now i now..
     
  12. Forty61

    Forty61 forum member

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    Soooo.. where we at? I was curious to see how this saga played out.
     
  13. Dino Dino Bambino

    Dino Dino Bambino I have a red car

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    He's probably either fixed it, burnt it to the ground, or pushed it off a cliff. ;)
     
  14. RLF9409

    RLF9409 My blood runs Ford blue!

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    LOL. I was wondering the same...
     
  15. Rick Simons

    Rick Simons Junior Member

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    I think you should take Dino's advice and get a leakdown test done before you go any further or spend any more money. Especially after seeing that damaged plug.