Blowin' Spark Plugs
pollenjesus
11-28-2005, 04:55 PM
Hey
I have a 2003 P71 and I have just blown my third sparkplug outta the heads. The plugs were torqued to spec so it ain't that. Right now I am just fixing the problem by installing heli coils. Does anyone know if there are some aftermarket heads available (performance or not) that will cap off my 4.6 and keep the sparkplugs from grenading outta the engine?
Ford suggesting replacing the heads with the same junk that is already on there.
Anyone else had sparkplugs blow out of the engine?
Paul.
I have a 2003 P71 and I have just blown my third sparkplug outta the heads. The plugs were torqued to spec so it ain't that. Right now I am just fixing the problem by installing heli coils. Does anyone know if there are some aftermarket heads available (performance or not) that will cap off my 4.6 and keep the sparkplugs from grenading outta the engine?
Ford suggesting replacing the heads with the same junk that is already on there.
Anyone else had sparkplugs blow out of the engine?
Paul.
l-m tech
11-29-2005, 12:35 PM
Hey
I have a 2003 P71 and I have just blown my third sparkplug outta the heads. The plugs were torqued to spec so it ain't that. Right now I am just fixing the problem by installing heli coils. Does anyone know if there are some aftermarket heads available (performance or not) that will cap off my 4.6 and keep the sparkplugs from grenading outta the engine?
Ford suggesting replacing the heads with the same junk that is already on there.
Anyone else had sparkplugs blow out of the engine?
Paul.
its a common problem .the new head has more thread area.the heads you have only have about 3 threads
I have a 2003 P71 and I have just blown my third sparkplug outta the heads. The plugs were torqued to spec so it ain't that. Right now I am just fixing the problem by installing heli coils. Does anyone know if there are some aftermarket heads available (performance or not) that will cap off my 4.6 and keep the sparkplugs from grenading outta the engine?
Ford suggesting replacing the heads with the same junk that is already on there.
Anyone else had sparkplugs blow out of the engine?
Paul.
its a common problem .the new head has more thread area.the heads you have only have about 3 threads
ModMech
12-03-2005, 11:47 AM
Paul,
There are two common causes for blowing plugs.
1) Incorrect installation procedures: Over/Under torquing the plug, using oil or anti-sieze on the threads during installation (that is a BIG NO-NO), or crossthreading the plug(s).
2) Excessive spark knock. This is often in-audible, but can result in cylinder pressures running 2x or more then designed for. Consequently, a plug is ejected.
There are numerous repair options that do not involve removing the head(s), most involve rethreading and installing a repair thread (similar to "Heli-Coil", but a solid piece). They have proven to be AS GOOD as new heads.
There are two common causes for blowing plugs.
1) Incorrect installation procedures: Over/Under torquing the plug, using oil or anti-sieze on the threads during installation (that is a BIG NO-NO), or crossthreading the plug(s).
2) Excessive spark knock. This is often in-audible, but can result in cylinder pressures running 2x or more then designed for. Consequently, a plug is ejected.
There are numerous repair options that do not involve removing the head(s), most involve rethreading and installing a repair thread (similar to "Heli-Coil", but a solid piece). They have proven to be AS GOOD as new heads.
BiggerJon
12-10-2005, 09:59 PM
i would personally recommend that you go with the compant 'time-sert' to fix this issue. they have a very good insert to fix your head.
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