How to prevent spark plug blowout

Discussion in 'SN95 4.6L Mustang Tech' started by Mike97gt, Jun 11, 2007.

  1. I have noticed a Lot of people on here having plugs blow out lately and I just wanted to go over what I think is the best way to prevent plug blowout.

    The most important thing is to check the torque on the plugs every 5k miles or so. ( every other oil change is fine)

    The factory torque spec is 13 ft-lb's you can set this with a 3/8 torque wrench, just make sure you are not reading in inch pounds


    If you do have a plug blow out you can repair it with a timesert kit and there is other kits coming on the market to repair striped threads. DO NOT use a regular helicoil, this can cause a hot spot and lead to detonation.
  2. Great info.

    Also make sure they are changed on a STONE COLD engine.
  3. Mike-

    is that 13ft/lbs with anti seize? do you recommend anti seize?
  4. He has said in previous threads that he doesn't use anti-seize. But if you look here The torque rating is the same if you want to use anti-seize.


    Thanks Mike!:flag:
  5. a small amount of anti seize is ok, it may help lube the threads. I personally don't use it but as long as you don't go nuts with it you will be fine.
  6. Actually F0rd recommeds that the engine be not hot nor cold but warm to the touch to remove the plugs.

    If the threads fail use a Time-Sert to repair it.

    ++TIME-SERT Ford Spark plug Thread Repair Kit



    Attached Files:

  7. I replaced my plugs and put in some NGK's (NGK Platinum Spark Plugs), torqued everything to spec and tried to start.

    On start up the cylinder one spark plug blew out and the threads stayed in the engine.

    Why would this happen and has this happened to anyone? Was it just a defected plug?
  8. DAAAAAAAAAMN!! That F ing blows....I have my stang all ready for a complete tune-up and fluid change...but this freaking scares the snot outta me. How often does this happen? A really assinine issue to worry about. God I love V8 Stangs, but Ford drops the ball waay to often
  9. They recommend the Motorcrafts for a reason - I'm not sure what that reason is - but those plugs seem to be more successful at staying in the heads than other brands from what I've read on here. If that happened to me I would probably take a sledgehammer to the engine, how frustrating that is. I wonder what would happen if you take it into a shop, have them change the plugs, and then the plugs blow. That would be an interesting scenario.
  10. blown plugs in newer heads?

    is this problem still happening with the newer engines have an 09 bullitt and am wondering if i should be on th elook out for this sounds like it is not a fun experience
  11. What does it mean when you guys refer to engine ticking? How does it sound like? What does your engine do?
  12. no, the 3v motors use a different spark plug design that breaks off when you take them out due to carbon buildup.

    they changed the design somewhat to fix the nonexistant problem mid year 08.

  13. :D Now that's funny.
  14. i had 2 plugs blow out at the same time and they were NGKs. maybe they just suck?
  15. I would say motorcrafts are good... When I first picked up my car #3 plug and cylinder had met at on point and all the threads are still good. I have auto lites in there now and no problems at all. Have even removed and installed a few times for compression checks and other things.
  16. ford has updated the motorcraft spark plugs on our car to the one thats threaded all the way...
  17. I had one blow out. Came outta nowhere. It took threads too.

    AND guys..that Time Sert kit looks expensive!!! I simply bought a cheap heli coil kit from Murrays on the HELP! rack for 11.99! It fixed my car great. It made dyno pulls after that, street races...etc. Never came back out. I also used loc-tite on the outside of the heli-coil.

    IF you use Anti-seeze, do NOT use the huge brush that is attached to the cap. Just use your finger, or a Q-tip to gently brush a TINY bit on the threads. There was an issue in a Mustang Magazine where these guys put new Trick Flow Aluminum heads on a 302. They showed a pic and the caption read "With aluminum heads, we couldn't resist giving the plugs a bath in anti-seeze." Or something along the lines of that. The pic showed a plug GOBBED with anti-seeze. I could only think of that fouling a plug out and possibly causing cylinder damage since it's a bit gritty. Anybody else remember that?
  18. OMG!! i am a mechanic in Detroit area(aka Ford country) and i have had a ton of these 3V nightmares come in. I have the damn special tool and everything to help remove the plug after it breaks.:mad: I will never understand the reason for that type of plug.:nonono: anyone that has seen a 3V plug knows what i am saying. oh and dont use anti seize for reasons that SVTTECH pointed out. it is not necessary and can sometimes cause more damage than good. just take your time, use proper tools(spark plug socket, plug gapper, etc.), torque to proper spec. then go back and check torque again before you start it up, and you will be just fine. :nice: also use di-electric grease in the spark plug wire or boot to help spark transfer from coil to plug. if you check the torque every so often this should never happen to you. :flag:
  19. Mike, what's the difference between a Helicoil and a Timesert set up? They seem nearly identical to me? Are the Timeserts made of a material that transfers heat better or something? :shrug:
  20. i myself, just pray to the mustang gods (lee iococca and carol shelby) that this never happens to me. if it does, ill use timeserts to replace them. i have had bad luck with heli coils in the past, timeserts have never let me down.