Broke Spark Plug In Head
11-07-2013, 08:09 AM
#1
Thread Starter
Join Date: Oct 2013
Location: AL
Posts: 37
Spark Plug Screws Too Far Into Head
This is a continuation of this thread: https://mustangforums.com/forum/4-6l...and-p0430.html
The spark plug extractors I'm seeing seem to be more for the electrode shell in the 3V engines, I'm pretty sure the porcelain has broken and separated from the thread body. The plug just spins like its being held in by the electrode. Once I get the top of the plug out and the thread body is still in the head, what extractor should I get?
The spark plug extractors I'm seeing seem to be more for the electrode shell in the 3V engines, I'm pretty sure the porcelain has broken and separated from the thread body. The plug just spins like its being held in by the electrode. Once I get the top of the plug out and the thread body is still in the head, what extractor should I get?
Last edited by kilr95ss; 11-09-2013 at 09:46 AM. Reason: Actually problem found
11-07-2013, 03:37 PM
#3
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Join Date: Oct 2013
Location: AL
Posts: 37
Crawled on top of the engine to get a better view. The spark plug has been screwed in so far that the hex part of it is almost below the bottom of the plug hole. Im guessing someone heli-coiled that hole and then the plug was tightened until the socket no longer would catch the hex.
Tried grabbing the top of the plug and unscrew it but ended up breaking it off. Used a long pair of hemostats and I could grab the very top part of the hex but they were not strong enough to unscrew it. Going to find a set of long jawed needle nose and see if those will unscrew it. The plug will move about a 1/4 turn but then it hits the rough pieces of the head around it that I've gouged trying to unscrew it.
Tried grabbing the top of the plug and unscrew it but ended up breaking it off. Used a long pair of hemostats and I could grab the very top part of the hex but they were not strong enough to unscrew it. Going to find a set of long jawed needle nose and see if those will unscrew it. The plug will move about a 1/4 turn but then it hits the rough pieces of the head around it that I've gouged trying to unscrew it.
Last edited by kilr95ss; 11-07-2013 at 03:40 PM.
11-07-2013, 04:32 PM
#4
1st Gear Member
Join Date: Oct 2013
Location: Allentown, Pennsylvania
Posts: 50
Most if not all sockets are tapered on the inside of the hex part.
I would try removing the taper with a grinder and see if it will grab the spark plug then. Maybe even taper the outside slightly.
I would try removing the taper with a grinder and see if it will grab the spark plug then. Maybe even taper the outside slightly.
11-08-2013, 04:24 PM
#5
Thread Starter
Join Date: Oct 2013
Location: AL
Posts: 37
mbeer, you are the man! Got the rest of the plug out, no problem! Looking at the plug hole, looks like the shoulder where the plug is supposed to seat is much lower. Think a spark plug indexer will allow the plug to seal where it is supposed to?
11-09-2013, 09:51 AM
#7
Thread Starter
Join Date: Oct 2013
Location: AL
Posts: 37
Before I buy a heli coil extractor, how can I verify there is a heli coil in the plug hole? Put a new plug in just for ****s and giggles and even with the modded socket [/B]mbeer[/B] suggested, I ran out of hex before the plug was near tight.
Even as far as the plug is going into the head, there is still piston clearance thank goodness! The old plug electrode showed no sign of being hit.
Even as far as the plug is going into the head, there is still piston clearance thank goodness! The old plug electrode showed no sign of being hit.
11-10-2013, 11:46 AM
#8
3rd Gear Member
Join Date: Nov 2012
Location: North Carolina
Posts: 574
Whether or not a heli coil is in there makes no difference for how far down the plug should go. The spark plug has to seal against the cylinder head so unless they machined the surface down where the plug would seal thread depth is irrelevant.
How tight are you trying to get it. Torque on those is 12-15lb/ft which you can achieve with two fingers and a 3/8" drive ratchet. They really never feel tight to me.
How tight are you trying to get it. Torque on those is 12-15lb/ft which you can achieve with two fingers and a 3/8" drive ratchet. They really never feel tight to me.
11-10-2013, 12:01 PM
#9
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Join Date: Oct 2013
Location: AL
Posts: 37
I looks as if the plug seat was drilled out for the insert because the hex goes into the head to the point that the socket looses contact with the plug and at that point the plug is still loose and can be turned with long needle nose pliers.
Not sure how the previous plug was tightened but it did not last long, only drove the car 7 days before the miss occurred and found the problem.
Not sure how the previous plug was tightened but it did not last long, only drove the car 7 days before the miss occurred and found the problem.
11-10-2013, 12:34 PM
#10
3rd Gear Member
Join Date: Nov 2012
Location: North Carolina
Posts: 574
Oh gotcha, maybe the opposite of a heli-coil happened and that's what it needs. Like maybe it blew out the plug and the previous owner didn't fix it.
Either way heli-coils look pretty obvious when they're in there. It's basically a coiled piece of wire. If you can look down into the cylinder to where you can see the piston with a flashlight you should be able to tell.
Either way heli-coils look pretty obvious when they're in there. It's basically a coiled piece of wire. If you can look down into the cylinder to where you can see the piston with a flashlight you should be able to tell.