I have an aluminum head and a spark plug broke off in it.
I was taking out the plug when the threads broke away from the plug. The plug and ceramic cam out but the threads stayed in the head. I sprayed it down with PB blaster and let it sit for about 3 days and than went back at it with an easy out. The easy out is spinning inside the plug threads(if that makes sence). I even tapped the easy out into the center hole of the plug threads and all that accomplished was the easy out spinning inside the plug threads again.

I am clueless now. Any other ideas to try????
I was hoping to have my truck running and on the road before snow flies...

Thank you

 

got me confused, did the part of the plug with threads break off from the hex part? That is usually all one piece.

 

That's strange, I would think the hex head would still be attached. Anyway, you might need to apply heat from a torch to the plug area and touch it a few times with candle wax to wick some lubricant down into the threads. You might need to helicoil the threads after you are done.

Using a thread chaser after removing the plugs is often worthwhile too.

Next time, be sure to use some anti sieze compound on the threads. Aluminum and steel do not mix well and will cause just the problem you are seeing. A tiny tube of compound may last you a lifetime.

Also ignore the 100,000 mile tuneup baloney, change your plugs at least every 50 and preferably 30. My experience with my 94 460 with iron heads is that the plugs will occasionally rust stuck if I go longer than 30K. I am told many shops will not touch the Cadillac Northstar because after 100K miles(as scheduled) the plugs are pretty much welded to the aluminum head.

Assuming you have a "hollow" plug jacket now in the thread, be careful to vacuum up any metal bits you may be shaving off. You don't want a lot of them getting down into the cylinder.

Good Luck,

Jim Henderson

 

Thank you.

Yes the hex part broke away from the threads. Take a spark plug and cut the threads off just under the hex and thats waht happened.

I was contimplating heat but was thinking it would melt the aluminum. Also I only have oxi-acedaline and I would end up burning electrical wires and who know what else.

Plug 2 stripped on its way out and I soaked 3 and 4 in PB blaster and they came out with no problam after soaking a couple days.

 

Did you try the easy out again -- sometimes you have to tap it more than gentle to get it to grab. Also if you have a torch with a small enough tip to heat the broken off part of the plug - not the head and let it cool - then try the easy out again. If there is enough room to reach it you may try welding a bolt into the broken off part of the plug - let it cool and then try to remove it. Once you do get it out I would recommend using some grease on the tap to help hold the material to the tap when chasing the thread. Good luck.

 

Oh man that is bad luck, just having threads and no hex. I usually cringe when I hear about bolts being broken off, but this sounds like a real PITA.

If you are brave/crazy, you might drill out the thread with gradually larger size bits until you have a thin shell left that might just crunch out of the way. Be sure to have a buddy with a strong vacuumsucking up the chips.

Good Luck,

Jim Henderson

 

Unfortunatly the truck is 1/2 hour from where I live (can't have more than 1 car at the condo) and I can't get there every night. I plan on tapping the easy out in more when I get a chance to get to it again. Drilling it out may be a decent option but I wanna keep out as much metal from the cylinder as possible and with my luck all the shavings will go into the cylinder and stick just well enough so the vacume cannot get it out.

I was told to use grease on the tap for the helicoil I need to put into cylinder 2.

I've been trying to get this thing up and running for about 5 months now. Not having time and havign issues with heads, yes heads. This is the 3rd head on the truck counting the original one and I removed 3 heads and do not want to do it again.

Thanks for all the input and suggestions.

 

Would it be possible or advisable to weld a chunk-o-steel to what's left of the spark plug so it can be turned out? The heat created in the process should ease the removal. What do you guys think? This is, of course, assuming that a welder is handy.

 

funny thing. I was thinking of taking some welding classes but there onle like 4 in a year and fill up quick(only 5 or 6 ppl per class) and I really don't have the 4 bills for the class. I have no welder and no one I know has a welder so it is pretty much out of the question and the plug hole is pretty deep. I've been trying a socket and extension on a rachet to turn the easy out as I cannot get anything on the easy out besides a socket. The head covers the easy out and the end of the easy out is just shy of being flush with the side of the head.

 

There are serveral different types of easy outs and I would try another one before I got carried away. The reverse spiral thread is one type and another that seems better for larger sizes actually looks like a tappered square punch. The edges bite into the old fastener.

 

7283-F250

I have re-read your original post several times trying to understand exactly what the situation is.
A: Are you saying that the easy out just isn't getting a bite on the remains of the plug?

B: Or is it turning the plug but making no progress unscrewing it?

If it is A, you may need a better easy out. That plug thread is very hard steel and you may have to drive the easy out into it pretty hard for it to get a bite. If PB Blaster didn't free it, then plug up the hole with something and flood the thread repeatedly with "Liquid Wrench" before you try the easy out again. There is an inherent problem here, the spark plug thread is a tube of very hard steel so that the easy out may tend to expand it instead of biting into it. This is not all bad though because that may help to break up the corrosion. If you have the patience, a combination of Liquid Wrench and shocks (impacts,) work together to free up frozen threads.

I don't know what engine you have, or the difficulty of seeing or reaching the problem area. But it sounds like what you need is an "impact driver," with an eight point socket that fits your easy out. That little set-up will be delivering a shock in the correct direction. Resist the temptation to hit it very hard. Keep flooding the threads with Liquid wrench, alternated with lightly using the easy out in the impact driver. The impact shock improves the penetrating effect of the Liquid Wrench and the Liquid Wrench will eventually break up the corrosion, eventually allowing you to extract the thread. This is all supposing that corrosion is the cause of the problem. (Always likely with dissimilar metals like aluminum and steel.)

If the basic problem came from someone crossthreading the plug into the head, or if the answer to my first question is B., the head will have to come off and go to a machine shop.