removing stripped spark plug - suggestions?

[pws]

I am parting out a 1990 white miata, and spark plug #3 is badly stripped
at the part where the spark plug attaches to the socket, not the thread
that the spark plug itself goes into. The spark plug is completely
stripped, and the part of the plug that the spark plug wire boot
attaches to is broken off. The remaining part of the plug is too far
down in the narrow well to grab with any tools that I know of, and I am
afraid that a tap and die would just send pieces down into the engine.

I have never seen this before. Has anyone else had this occur and did
you find a solution? From what I can see, I am going to have to take off
the head and use vise grips to get the plug out.

Thanks,

Pat

[Chas Hurst]

Post by pws
I am parting out a 1990 white miata, and spark plug #3 is badly stripped
at the part where the spark plug attaches to the socket, not the thread
that the spark plug itself goes into. The spark plug is completely
stripped, and the part of the plug that the spark plug wire boot
attaches to is broken off. The remaining part of the plug is too far
down in the narrow well to grab with any tools that I know of, and I am
afraid that a tap and die would just send pieces down into the engine.
I have never seen this before. Has anyone else had this occur and did
you find a solution? From what I can see, I am going to have to take off
the head and use vise grips to get the plug out.
Thanks,
Pat

It's not possible to grasp that plug with any vise grips I'm familiar with;
head on or off.
Stripping the hex on the spark plug isn't unheard of. The remedy is to grind
a bevel or chamfer around the end of the spark plug socket so that it can
reach lower in the spark plug well and grip what ever is left of the hex. If
the hex is truly and completely gone, a 20mm 12 point deep socket driven
over the remains of the plug might work.

[Bryan]

I am parting out a 1990 white miata, and spark plug #3 is badly stripped at
the part where the spark plug attaches to the socket, not the thread that
the spark plug itself goes into. The spark plug is completely stripped, and
the part of the plug that the spark plug wire boot attaches to is broken
off. The remaining part of the plug is too far down in the narrow well to
grab with any tools that I know of, and I am afraid that a tap and die
would just send pieces down into the engine.
I have never seen this before. Has anyone else had this occur and did you
find a solution? From what I can see, I am going to have to take off the
head and use vise grips to get the plug out.
Thanks,
Pat

Last resort, you could sacrifice a socket... Apply some JB Weld and let it
set over the plug until it dries. Never tried it, but it sounds reasonable
as long as you're careful not to "weld" the socket to the camshaft cover.
Guess I would try this as a last resort.

[Chuck]

There is a type of socket that has a bunch of needles inside. These will
form around the damaged plug, and allow it to be removed. A big if is to get
the correct size that will fit in the well and around the plug. Otherwise,
the steel filled epoxy method sounds good. Since sockets are almost always
slightly oily driving the mess out afterwards should be reasonable.

Post by Bryan

Post by pws
I am parting out a 1990 white miata, and spark plug #3 is badly stripped
at the part where the spark plug attaches to the socket, not the thread
that the spark plug itself goes into. The spark plug is completely
stripped, and the part of the plug that the spark plug wire boot attaches
to is broken off. The remaining part of the plug is too far down in the
narrow well to grab with any tools that I know of, and I am afraid that a
tap and die would just send pieces down into the engine.
I have never seen this before. Has anyone else had this occur and did you
find a solution? From what I can see, I am going to have to take off the
head and use vise grips to get the plug out.
Thanks,
Pat

Last resort, you could sacrifice a socket... Apply some JB Weld and let
it set over the plug until it dries. Never tried it, but it sounds
reasonable as long as you're careful not to "weld" the socket to the
camshaft cover. Guess I would try this as a last resort.

[pws]

Post by Chuck
There is a type of socket that has a bunch of needles inside. These will
form around the damaged plug, and allow it to be removed. A big if is to get
the correct size that will fit in the well and around the plug. Otherwise,
the steel filled epoxy method sounds good. Since sockets are almost always
slightly oily driving the mess out afterwards should be reasonable.

Thanks for the responses, I will look for this needle socket and see if
it looks likely to do the job, otherwise I will go with the JB Weld
method. My main concern is that JB Weld is very drippy and takes a long
time to set up, so I would really need to protect the spark plug from
becoming permanenty attached to the engine, as was mentioned before by
Bryan. I will also try the 20mm socket first, but the hex on the spark
plug looks like it is truly gone, someone has tried to remove this
before I got to it.

There is a quick-set version of JB Weld, I'll probably try it first and
see if it holds on enough to break the spark plug free. I am thinking
about stuffing the area below the socket contact point with plastic wrap
or some other non-absorbent material. Any other suggestions on keeping
the bonding agent out of the spark plug threads/manifold area would be
very welcome.

Sacrificing a socket is no big deal, as I think that this is a good,
recently serviced engine that I can use in another miata or sell it if I
can get that plug out.

Thanks again and I will let you know if it works.

Pat

[Leon van Dommelen]

Post by pws

Post by Chuck
There is a type of socket that has a bunch of needles inside. These will
form around the damaged plug, and allow it to be removed. A big if is to get
the correct size that will fit in the well and around the plug. Otherwise,
the steel filled epoxy method sounds good. Since sockets are almost always
slightly oily driving the mess out afterwards should be reasonable.

Thanks for the responses, I will look for this needle socket and see if
it looks likely to do the job, otherwise I will go with the JB Weld
method. My main concern is that JB Weld is very drippy and takes a long
time to set up, so I would really need to protect the spark plug from
becoming permanenty attached to the engine, as was mentioned before by
Bryan. I will also try the 20mm socket first, but the hex on the spark
plug looks like it is truly gone, someone has tried to remove this
before I got to it.
There is a quick-set version of JB Weld, I'll probably try it first and
see if it holds on enough to break the spark plug free. I am thinking
about stuffing the area below the socket contact point with plastic wrap
or some other non-absorbent material. Any other suggestions on keeping
the bonding agent out of the spark plug threads/manifold area would be
very welcome.

Wax? Oil? They always say the surface should be clean.

Leon

Post by pws
Sacrificing a socket is no big deal, as I think that this is a good,
recently serviced engine that I can use in another miata or sell it if I
can get that plug out.
Thanks again and I will let you know if it works.
Pat

[Chuck]

Leon,
Tools don't rust if they have an oil film. Besides, not everyone has the
spare time to do a hospital grade cleanup.

Post by Leon van Dommelen

Post by pws

Post by Chuck
There is a type of socket that has a bunch of needles inside. These will
form around the damaged plug, and allow it to be removed. A big if is to get
the correct size that will fit in the well and around the plug. Otherwise,
the steel filled epoxy method sounds good. Since sockets are almost always
slightly oily driving the mess out afterwards should be reasonable.

Thanks for the responses, I will look for this needle socket and see if
it looks likely to do the job, otherwise I will go with the JB Weld
method. My main concern is that JB Weld is very drippy and takes a long
time to set up, so I would really need to protect the spark plug from
becoming permanenty attached to the engine, as was mentioned before by
Bryan. I will also try the 20mm socket first, but the hex on the spark
plug looks like it is truly gone, someone has tried to remove this
before I got to it.
There is a quick-set version of JB Weld, I'll probably try it first and
see if it holds on enough to break the spark plug free. I am thinking
about stuffing the area below the socket contact point with plastic wrap
or some other non-absorbent material. Any other suggestions on keeping
the bonding agent out of the spark plug threads/manifold area would be
very welcome.

Wax? Oil? They always say the surface should be clean.
Leon

Post by pws
Sacrificing a socket is no big deal, as I think that this is a good,
recently serviced engine that I can use in another miata or sell it if I
can get that plug out.
Thanks again and I will let you know if it works.
Pat

--
Leon van Dommelen :) Bozo, the White 96 Sebring Miata .)
EXIT THE INTERSTATES (Jamie Jensen)

[pws]

Post by Chuck
Leon,
Tools don't rust if they have an oil film. Besides, not everyone has the
spare time to do a hospital grade cleanup.

I think that what he is saying is to use oil (or wax) to keep the JB
Weld from bonding to the engine and spark plug threads. The instructions
on JB Weld say to apply to a clean, non-oily surface. That is probably
what he was referring to, not the condition of the tools themselves.

Pat

[pws]

Post by Leon van Dommelen
Wax? Oil? They always say the surface should be clean.

Wax, I never thought of that. It should be easy enough to drip some in
around the edge of the plug contact point with a candle and let it dry
before trying to bond the socket to the plug. I'll give it a shot this
weekend.

Thanks,

Pat

[Dana H. Myers]

Post by Leon van Dommelen
Wax? Oil? They always say the surface should be clean.

But - the goal here is not to bond to the surface, the goal
is to create a form-to-fit socket around it. So wax/oil
that prevents the epoxy from permanently bonding to the
plug and/or socket (or even head casting) doesn't seem
to be problem at all, as long as the epoxy cures and
hardens.

Right?

Cheers -
Dana

P.S. Good luck, Pat, hope you get it out...

[pws]

Post by Dana H. Myers

Post by Leon van Dommelen
Wax? Oil? They always say the surface should be clean.

But - the goal here is not to bond to the surface, the goal
is to create a form-to-fit socket around it. So wax/oil
that prevents the epoxy from permanently bonding to the
plug and/or socket (or even head casting) doesn't seem
to be problem at all, as long as the epoxy cures and
hardens.
Right?
Cheers -
Dana
P.S. Good luck, Pat, hope you get it out...

Thanks, just tried it tonight, we'll see tomorrow after it dries.

Pat

[Bryan]

Post by pws

Post by Dana H. Myers

Post by Leon van Dommelen
Wax? Oil? They always say the surface should be clean.

But - the goal here is not to bond to the surface, the goal
is to create a form-to-fit socket around it. So wax/oil
that prevents the epoxy from permanently bonding to the
plug and/or socket (or even head casting) doesn't seem
to be problem at all, as long as the epoxy cures and
hardens.
Right?
Cheers -
Dana
P.S. Good luck, Pat, hope you get it out...

Thanks, just tried it tonight, we'll see tomorrow after it dries.
Pat

So, did it work??

[pws]

Post by Bryan

Post by pws

Post by Dana H. Myers

Post by Leon van Dommelen
Wax? Oil? They always say the surface should be clean.

But - the goal here is not to bond to the surface, the goal
is to create a form-to-fit socket around it. So wax/oil
that prevents the epoxy from permanently bonding to the
plug and/or socket (or even head casting) doesn't seem
to be problem at all, as long as the epoxy cures and
hardens.
Right?
Cheers -
Dana
P.S. Good luck, Pat, hope you get it out...

Thanks, just tried it tonight, we'll see tomorrow after it dries.
Pat

So, did it work??

No, not even close. I don't think that the cold weld bonded the socket
threads like I feared it would, but the socket tears off before it
begins to turn the plug. It is starting to look like quite a bit of
engine dissassembly will be required before this can be fixed, and I am
not sure of the engine's condition, so I will probably just end up
selling the engine's parts rather than trying to use it or sell it as a
whole engine.

It is amazing to see how much time and trouble would have been saved if
the previous owner had simply applied anti-sieze compound to the spark
plug threads, but that would have added about 10 cents worth of
materials and 10 extra seconds of time. :-\

pat

[BRUCE HASKIN]

Pat, If you take the cam cover off, you might be able to get a better
shot at the plug.

Before I would take the head off, I think I would :
Pull the cam cover.
Break the top of the plug off.
Chip out all of the porcelin.
Suck the chips out with a vac.
Pull the center electrode out (vac again )
Use an "E-Z out" on an extention and wrench.
(I know they make one that will fit)

This might save you some work :-)

Lots of luck

Bruce RED '91

[somebody]

Don't know if this was mentioned or not.
There is a wedge-type socket that is used to remove stuck and rounded bolts.
Also there is an ez-out type socket for rounded nuts.
Try a specialty auto parts store. Or someone that sells Proto tools.

[pws]

Post by somebody
Don't know if this was mentioned or not.
There is a wedge-type socket that is used to remove stuck and rounded bolts.
Also there is an ez-out type socket for rounded nuts.
Try a specialty auto parts store. Or someone that sells Proto tools.

The main problem is that the spark plug is pretty deep in a hole that is
not much bigger than the width of the spark plug itself, but I will go
scour the tools section until I can find something that looks like it
will work,

Thanks for all of the suggestions, here goes one more try,

Pat

[pws]

Post by BRUCE HASKIN
Pat, If you take the cam cover off, you might be able to get a better
shot at the plug.
Pull the cam cover.
Break the top of the plug off.
Chip out all of the porcelin.
Suck the chips out with a vac.
Pull the center electrode out (vac again )
Use an "E-Z out" on an extention and wrench.
(I know they make one that will fit)
This might save you some work :-)
Lots of luck
Bruce RED '91

Thanks,
I have already pulled the cam cover and broken off top of the plug. The
porcelain is tough, but a drill should take it out. I have a vacuum
cleaner extension that fits into the spark plug well, so removing the
pieces is no problem. I will go look for an appropriately sized E-Z out
tool tomorrow.

Thanks again and I will let you know how it goes,

Pat