spark plugs

[woppy balboa]

Does anyone have any tips on how to get seized spark plugs out? I've been spraying penitrating fluid for days. I got 1 and 2 out of each side fairly easy but the rear 2 are stuck good. they're not in the best shape so I'm carful not to round them off.

 

[Jessfly1]

Re: spark plugs

Heat the block around the plugs with a torch. This will expand the meatal, hopefully enough to get them out. If your still having problems, heat the metal again and put some candle wax around the plug so the heat will cause the wax to melt and absorb into the threads. If you dont have a tourch try some pb blaster and a breaker bar. This is a horrible situation if you cant get them out.

 

[basbalj288]

Re: spark plugs

I agree on heating the plugs. That has worked for me in the past not only on spark plugs but also on plumming issues.

 

[wellsc1]

Re: spark plugs

You said the plugs are starting to round off, but if you think they will hold up to a little impacting, try a 3/8" impact ratchet if you dare at this point.

I swear by PB Blaster spray penetrant. That stuff seems to work when nothing else does. Give it some time to do its stuff, even overnight, periodically apply a spray.

Hopefully, whatever gets the plugs out, the threads will remain solidly intact.

 

[Gromulin]

Re: spark plugs

Kano Kroil..if you can find it. Best penetrating oil there is. Good luck.

 

[TiredoleBoy]

Re: spark plugs

when I had this on a car I would break the ceramic off and tap on a smaller metric socket. It has to be just a slight bit smaller than the 3/4 or 5/8 sockets. But this was worse case only.

 

[K9Deuce]

Re: spark plugs

This will work. get some MAP gas ( MAP gets alot hotter then propane and will fit onto a regular propane plumbers torch) Heat up the area around the plugs get it real hot. Now cool it off with water and dont be afraid to use alot , then repeat the process three times. The heat coupled with the quick cooling will break the corrosion free. Plus You dont realy want to torque on those plugs when they are hot because the metal is softer and you will just round off the plug surface. This always works, just be sure to get the surface cooled quick thats what breaks away the corrosion.

 

[acuraguy81]

Re: spark plugs

I like what k9 says that sounds like the best choice so far never done it but good idea for sure!!!!

 

[bruceb58]

Re: spark plugs

Kano Kroil..if you can find it. Best penetrating oil there is. Good luck.

+1 on the Kroil. Way better than PB.

 

[full stringer]

Re: spark plugs

I totally agee with that method because it"s the same principle as a boiled egg after you boil it you toss it in cold water and the egg will seperate from its shell might want to run a thread chaser after your done and reinstall the new plugs with anti seize good luck bro we've all been there lol!

 

[Gromulin]

Re: spark plugs

This will work. get some MAP gas ( MAP gets alot hotter then propane and will fit onto a regular propane plumbers torch) Heat up the area around the plugs get it real hot. Now cool it off with water and dont be afraid to use alot , then repeat the process three times. The heat coupled with the quick cooling will break the corrosion free. Plus You dont realy want to torque on those plugs when they are hot because the metal is softer and you will just round off the plug surface. This always works, just be sure to get the surface cooled quick thats what breaks away the corrosion.

I like the theory...but sounds kinda scary. In the gunsmithing world rapid heating and quick quenching can do Very Good or Very Bad things to metal, depending on very specific application.

If the plugs are *that* stuck...gotta wonder: why? how?. Usually some good penetrating oil and careful use of heat unsticks most thing that can be un-stuck*

disclaimer: this opinion comes more from personal experience with old rifles, old motorcycles and old cars, the marine environment is...er..unique.

 

[fat fanny]

Re: spark plugs

I know these heating and quenching methods do work but also remember that cast never reacts well to sudden changes in tempetature That's why when you weld it it is recomended that you pre and post heat the subject area to bring it slowly back to ambiant temp. I hope it works out for you be patient and cautious proceeding or it will cost you. I would bet a buck those plugs aren't marine grade!!!!!!!!

 

[bruceb58]

Re: spark plugs

I wouldn't worry about the block at all with getting it too hot. Its getting no where near as hot as when you are welding and the small amount of water that hits it won't change the temp as fast as you think....just too much mass.

 

[NHGuy]

Re: spark plugs

What engine are you wrenching? I'm new last year to this world and found (through this forum) that I needed a milled down spark plug socket to get onto my plugs. Before I shaved down my plug socket I couldn't turn some of my spark plugs due to interference from my exhaust manifold.

 

[45Auto]

Re: spark plugs

Only problem you'll have with heat and cast iron engine blocks or heads is if you get it so hot it cracks. And there's no way you're going to come close to that with a little MAPP or propane torch, it's hard enough with oxy-acetylene.

No such thing as heat treatment on cast iron parts, so you don't have to worry about affecting that:

Pure iron, wrought iron, and extremely low-carbon steels have very little hardening properties and are difficult to harden by heat treatment. Cast iron has limited capabilities for hardening.

http://www.globalsecurity.org/military/library/policy/navy/nrtc/14250_ch2.pdf​

So heat it up and cool it down as much as you like. Krano Kroil is BY FAR the best penetrating oil you can get.

Worst thing that will happen is you have to pull the heads so you can get to the stuck plugs, carefully drill the plug shells out without hitting the threads, and run a tap back through the holes. Or you can always use a Heli-coil if you totally screw up the threads .....

 

[woppy balboa]

Re: spark plugs

Thanks for all the help. The motor is a 302 ford v8 in a '74 Sterncraft. I just bought it with the one broken and seized plug. I have been using pb blaster and liquid wrench all week. I got 5 of the 8 plugs out. I now have one still stuck and 2 sheered off. I read about the kroil and an easy out. I happened to have both of these where I work. Like a miricle. I'll try this today.

 

[Bondo]

Re: spark plugs

This will work. get some MAP gas ( MAP gets alot hotter then propane and will fit onto a regular propane plumbers torch) Heat up the area around the plugs get it real hot. Now cool it off with water and dont be afraid to use alot , then repeat the process three times. The heat coupled with the quick cooling will break the corrosion free. Plus You dont realy want to torque on those plugs when they are hot because the metal is softer and you will just round off the plug surface. This always works, just be sure to get the surface cooled quick thats what breaks away the corrosion.

Ayuh,.... I Completely Agree,.... 110%,... I do it darn near Everyday....

I carry Ox/Ac on my pickup,...Mapp'll porbably work though,...
My Technique is slightly different,...

Being able to SEE the offending part is of concern,...
I heat the Piece that's Stuck, the remains of the sparkplug, not so much any of the surrounding head area...
Concentrate the heat to the shell/ nut/ bolt/ Whatever, itself,...
If you can get those shells to Atleast a Glowing Red condition,.... Brighter the Better, Just short of Melting is Best...

Douse it with cold water,...
No worry about the head, or cylinder with the heat, nor the water,.. Clean it out later...

It usually only takes a single application to relieve things,...
A shot of whatever P-oil,+ it'll probably come out with your Fingers....
If it Don't work,... It wasn't Hot enough...

Btw,.... The Only guys who try to turn Hot fasteners, are the 1s whom just don't know any Better...

 

[woppy balboa]

Re: spark plugs

Well, unfortunatly guys, none of these methods worked. I went through a can of PB Blaster, Kano Kroil, half a can of Liquid Wrench, and even tried the trans. fluid/ acetone mix. Heated and cooled the head (all I had was Mapp gas) and was on the verge of breaking the easy out more than once. Finally yesterday I took on the task of removing the head to have it drilled out. After a week and a half fighting with the spark plugs, removing the head took about an hour.