Re-Tapping Sparkplug hole.

[67coupe351w]

So my buddy is drivin his 85 Toyota celica down the road today and it Blows a sparkplug right out of the head.

I know I know its a toyota and it should be thrown away but My question is this. Is it at all possible to drill and tap and helicoil the hole without removing the head and using a really big shop vac...Or am I just being dumb about not wanting to pull the head?

 

[crushnut]

Why would you risk it? Its not your car, so if he is ok with it then do it, but its something that i would never advise someone to do.

Good Luck

 

[Ozsum2]

Too much anti-seize.

 

[Hack]

Too much anti-seize.

You can never have too much anti seize!! All my clothes are shiny silver.

Grease is good, it prevents rust. Corrosion is what weakens threads, because that material is just gone.

 

[dodgestang]

I just did this repair on my DD Neon.

Fill the grooves in the heli coil tap with bearing grease and go to town.

When down, I also pulled the coil wire, and crank the motor a couple time to blow anything out that may have gotten past the grease. They just set the heli coil threads in and your done.

Been 3k miles without a problem

 

[PONY XPRESS]

Your buddy's plug may have just been loose when it blew out. He may luck out running a 14mm or 18mm plug tap through the hole. And yes you can have too much anti-seize on a plug. I have seen it where the plug will not fire because it could not ground with all the anti-seize on it.

 

[Ozsum2]

Your buddy's plug may have just been loose when it blew out. He may luck out running a 14mm or 18mm plug tap through the hole. And yes you can have too much anti-seize on a plug. I have seen it where the plug will not fire because it could not ground with all the anti-seize on it.

Yep. I have heard of the new Lightnings blowing them out, but that's another horse.

 

[Hack]

Your buddy's plug may have just been loose when it blew out. He may luck out running a 14mm or 18mm plug tap through the hole. And yes you can have too much anti-seize on a plug. I have seen it where the plug will not fire because it could not ground with all the anti-seize on it.

I don't believe that.

I've put too much anti seize on a plug before. It just squeezes out and makes a mess. It's possible the plug didn't fire because it wasn't tight, but anti seize isn't hard. It's grease!

 

[PONY XPRESS]

HACK

With alloy heads and lots of antiseize you will lose your ground. This is common knowledge with the VW air cooled crowed. Also, use a rag to wipe your hands instead of using your clothes. Didn't your mother teach you anything?

 

[390Fe]

Is the Toyota an aluminum or cast iron head? I'm guessing aluminum - drilling and tapping that shouldn't be a big deal if some aluminum gets into the cylinder- just grease up the bit to catch the chunks and go SLOW so you can clean off the excess and regrease. Plus it's only a toyota anyway.

 

[Hack]

HACK

With alloy heads and lots of antiseize you will lose your ground. This is common knowledge with the VW air cooled crowed. Also, use a rag to wipe your hands instead of using your clothes. Didn't your mother teach you anything?

Hehe, funny about the clothes.

I still don't believe that grease is hard enough to not deform when you tighten the spark plug. It will squish out. You HAVE to have metal to metal contact in order to have the plug get tight. But hey, I've never had alloy heads - are you supposed to finger tighten the plugs in them or something?

 

[Ozsum2]

Hehe, funny about the clothes.

I still don't believe that grease is hard enough to not deform when you tighten the spark plug. It will squish out. You HAVE to have metal to metal contact in order to have the plug get tight. But hey, I've never had alloy heads - are you supposed to finger tighten the plugs in them or something?

No, it just provides the plug with lubrication to go ahead and loosen.

 

[67coupe351w]

Well guys crisis avoided...I was assuming the worst that the threads were completely gone...someoen hadnt tighted the plug down and it wiggled loose and just mangled the uper 2ish threads...I was able to get the plaug to go in and tighten down. Thank you for yur thoughts though guys!

 

[slapper]

I've taken a thin cotton rope before and soaked it in oil and fed it down into the cylinder to catch any debris, and then pull it out with a pick/ hemostats, etc.

 

[PONY XPRESS]

67coupe351

Good deal. As I suspected, you still may want to run a tap through the top threads to clean them up.

Hack

What happens with the antiseize is after a short period of time & the heat of the heads, the gooey paste now gets hard & you can loose a ground. I first witnessed this in an SCCA Formule Vee. Fellow had a miss that was driving him crazy. Pulled plugs, antiseize was hard, cleaned up & was good to go.

 

[Hack]

Hack

What happens with the antiseize is after a short period of time & the heat of the heads, the gooey paste now gets hard & you can loose a ground. I first witnessed this in an SCCA Formule Vee. Fellow had a miss that was driving him crazy. Pulled plugs, antiseize was hard, cleaned up & was good to go.

Hmm. I expect the plug was loose. If he had just tightened it that would have taken care of the problem. It's easy to make assumptions about what is happening. Your example doesn't prove your point.

I've used gobs of antiseize on all my cars for 15+ years and never had a problem. The antiseize I've used never gets hard either. I can always wipe it away with a rag. No wire wheel or grinder required.

I've always had cast iron heads in all my vehicles. I believe that a steel plug thread in an aluminum head might exhibit all sorts of odd behavior. I can see where someone might easily attribute that behavior to grease or something. I guess a guy could always just thread the plug in with no grease and take his chances. I won't, though.

 

[Ozsum2]

Hmm. I expect the plug was loose. If he had just tightened it that would have taken care of the problem. It's easy to make assumptions about what is happening. Your example doesn't prove your point.

I've used gobs of antiseize on all my cars for 15+ years and never had a problem. The antiseize I've used never gets hard either. I can always wipe it away with a rag. No wire wheel or grinder required.

I've always had cast iron heads in all my vehicles. I believe that a steel plug thread in an aluminum head might exhibit all sorts of odd behavior. I can see where someone might easily attribute that behavior to grease or something. I guess a guy could always just thread the plug in with no grease and take his chances. I won't, though.

Steel threads in an alloy head will molecularly bond to it. I've never used it with steel on iron. I have seen it used, but sparingly. A little dab will do ya, just like Brillcream.

 

[PONY XPRESS]

Steel threads in an alloy head will molecularly bond to it. I've never used it with steel on iron. I have seen it used, but sparingly. A little dab will do ya, just like Brillcream.

I agree

Hack

Not sure what point I was making that you missed. My first post to this thread had a correct assumption. It's a must for alloy heads & can cause lose of ground.

 

[Hack]

I agree

Hack

Not sure what point I was making that you missed. My first post to this thread had a correct assumption. It's a must for alloy heads & can cause lose of ground.

I'm not sure I missed anything. I have used anti seize a lot and I disagree with your statement regarding losing ground.

..and I should probably quit posting since I'm repeating myself.

Have a great day!

 

[skywalker]

Your buddy's plug may have just been loose when it blew out. He may luck out running a 14mm or 18mm plug tap through the hole. And yes you can have too much anti-seize on a plug. I have seen it where the plug will not fire because it could not ground with all the anti-seize on it.

*raising BS flag to full mast* anti-seize conducts very well. There was another problem altogether.