My sparkplug is very difficult to unfasten. Three of my four sparkplug do
not unfasten from the engine's top. I use very high force ΄to unfasten them
but they are not unfasten, I tryed both with cold engine and varm engine -
the do not unfasten. What should I do for unfasten the sparkplug without
broken them in their enginehole in the enginetop. Please help me.
Soak with penetrating oil for a few days. Warm engine up, apply
liquid nitrogen to sparkplug base (but not to cylinder head). Remove.
Purchase good Snap-On Socket. Connect to Johnson bar, Put pipe
extender on, Unscrew plug & threads. Drill out spark plug hole while
maintaining positive air pressure in cylinder. Install Heli-coil to
replace stripped threads. Put anti-seize on new spark plugs. Pray
that no metal bits fell between the piston & cylinder wall, start
Years & years ago we used to use R-12 to cool the plugs but that's a
huge no-no nowadays. Only hospitals are allowed to dump CFC's into
the atmosphere nowadays.
If you don't have alternate transportation, be prepared for fixing the
stripped hole if necessary. Try the penetrating oil treatment the day
before attempting removal again. Make sure you keep your wrench
straight so you are not pulling the plug sidewise. Use the bar
extender if more force is needed. Good luck.
It isn't quite as cold, but try a can of compressed air for blowing dirt
out of PC proccessors and keyboards and such. The trick is that you
must hold the can upside down so the liquid comes out instead of the
gas. Don't spray it on yourself unless you like frostbite.
As far as CFC's, I read that the the proccess used to make the engines
for the space shuttle released more CFC's than everything else in the
The goal, is to contract the metal of the sparkplug base from the
head. So. If the Start spray (likely ether) is used to cool the plug
faster than the head you must ensure that it only lands on the plug
(perhaps make a paper funnel to surround the plug at the base). It
is the difference in temperatures that "should" allow the plug to come
Another thing that is sometimes tried is using a shock wave in
addition to the force to aid in the removal. "some" ratchet's allow
you to apply torque & strike the piece connecting through to the
extension or the socket. They tend to have a lever along the handle
portion of the rachet to change direction. If you don't have one
explain to the tool guy what you're looking for. (Or use a Johnson
If you are unfortunate enough to twist off one of your spark plugs, here is what
worked on mine (a longer story that I attempted to post did not come thru....
perhaps because it was a "cross-post"?)...anyway, here is the short version:
The remaining shell of threads in the head was heated to cherry-red with a
tip on an oxygen/acetyln torch. I then immediately sprayed them with a cold spray
labelled as capable of -50 deg F (purchased at Radio Shack). Then used a square
tapered bolt extractor (some might refer to it as an "easy-out") size 5/16", to
successfully screw out the remains of the spark plug.
Aluminum or iron head?
Soak the plug bases in carb cleaner to soften the carbon in the threads,
then use plenty of PB Blaster or similar once they break loose.
It seems counterintuitive, but it often helps to tighten a frozen plug(or
bolt) a bit, before trying to loosen it. Once it starts to move, keep
working it back and forth rather than trying to back it all the way out.
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