My mechanic broke off a sparkplug trying to remove it from the engine on my 4runner and I am trying to research possible solutions. It broke off halfway down the threads, so that half of the bottom metal part is still in the engine head. I was thinking using and easyoff extractor but worry about metal pieces includint the electrode tip falling into the cylinder. Anyone have ideas or experience with this? thanks, rick
why are you worrying about it if your mechanic broke the sparkplug. let him figure it out and deal with it.
If it broke coming out it's not the mechanic's fault, unless he or his dealership installed said plug.
": P" wrote: why are you worrying about it if your mechanic broke the sparkplug. let him figure it out and deal with it. ^^^^^^^^^^^^^^^^^^ It's not really the mechanic's fault, so I think he would be justified in charging to remove the head and take the plug out at the bench, using an easy-out, a drill, or whatever means he has available.
I assume you are trying to reduce the labor. I would go ahead and use an Easy-out, and then, before running the engine, turn it over with the starter for a minute or so, to pump air in and out the spark-plug hole. This will most likely blow out any small stuff that may have fallen in. In addition, you could position the piston at bottom-dead-center, and then shove a vacuum hose in and wiggle it around a lot. You could also dump in some oil, and then turn the engine by hand, pumping the oil out the spark-plug hole, which will also help flush out things that could have fallen in.
If any really little stuff remains, I would expect it to be blown out the exhaust valve when the engine is started, causing no harm.
If the threads in the spark-plug hole are damaged in the process of removing the plug, it's very easy to Helicoil it. A Helicoil is actually stronger than cast iron or aluminum, so the results are better than new.
Slightly OT: I once had a mechanic Helicoil the spark plug hole in the number 3 cylinder of my VW, using a mirror. There was someone with real mechanics hands.
semidemiurge wrote in article ...
I would worry LESS about the chips and metal pieces falling inside the cylinder and MORE about how I would remove the hardened piece of easy-out that breaks off in the head.......................
They SHOULD be called "hole-pluggers"..........
posted to RCM only
On Wed, 18 Jul 2007 04:46:24 -0000, with neither quill nor qualm, semidemiurge quickly quoth:
Chances are good that you already have crap in the bore from the break. Do not run the engine.
Take the vehicle to another mechanic (A -real- one this time) who will pull the head for repair. There is no other safe method, -period-, and I say this as a retired mechanic. Then take the bill to your monkey and have him pay it. His ham-handedness crossthreaded it and got it in so tight that it broke in two. Whadda freakin' maroon!
P.S: I did tuneups for years and never had a sparkplug seize on the way OUT of the head. I had to use a tap a couple times due to crossed starter threads, and it was magnetized to prevent chip loss into the bore. I also ran a long-tubed airgun tip into the bore to blow chips of the outside before replacing the sparkplug. I learned then to always check the plug threads before even trying to start them.
- Metaphors Be With You -
If he doesn't already, your mechanic will!
He broke it. STAY AWAY, let him fix it. What happens if your suggestion goes arwy?
Second that.
-Carl
Larry Jaques wrote in article ...
Obviously, you got out of the bidness before the proliferaton of steel spark plugs in aluminum heads - compounded by 100,000 mile change intervals which give the electrolytic action between differing metals longer to chemically weld the plug into the head.
I tried to change plugs in my S-10 4 cylinder back in the 90s. One plug snapped just above the threads. After a firm decision to always change plugs on a COLD engine, I pulled the head, checked the bore for debris, then took the head downstairs in the basement, tapped out (as in rod and hammer) the ceramic core, then used a _straight_ EZ-Out to turn the shell out. Had to use a 4" pipe as a cheater...
Put > My mechanic broke off a sparkplug trying to remove it from the engine
Anti-seize compound is your friend...
Aluminum screws holding down a distributor cap on a steel boss = more trouble than you want. Thank God for nylon wire ties... Alternator mounting bolt was totally froze (I let a local shop change it).
Man, you can say that again! I've used "easy"-outs a bunch of times and most turned into, as you say, hole pluggers. Then you really have a problem: How do you drill out that hardenen steel? Interestingly enough, apparently I never learn the lesson. Each time I have a broken bolt, I look at my collection of easy-outs and think, maybe this time... jor
'Never hear of a "left-hand drill"? For many extraction jobs, that's the ticket. If sized appropriately, it doesn't tend to expand the item in the hole, rather, it "grips" from the top.
LLoyd
If he managed to break a sparkplug off down into the threads, you have a lot more to worry about than a few metal flakes getting into the engine. That plug must be welded in. I've NEVER, in all my years of working on cars and trucks, seen the metal part of a plug break. The ceramic, yes, the metal, no. If you have to get crazy with it, an oil soaked rag in the top of the cylinder, with the piston at TDC should take care of most particles. After you get the remains of the plug out, carefully remove the oil soaked cloth. The metal shavings, for the most part, should come out with it. If all else fails, he will have to remove the head and drill it out and retap the head.
Jim Chandler
I can't speak for Larry, but I worked for years for a company whose every engine has an alloy head. Never ever had a problem, even with extended service intervals.
-Carl
Don't be TOO sure....
About a year ago my daughter had her Olds tuned up, which included a new set of plugs. A week later the engine started running rough and the shop which did the job found that the ground electrode on one plug had disappeared, and installed a new plug at no cost. The car seemed to be running fine after that.
Nearly a year later when she went to get the car through state inspection it failed because its computer "said" one cylinder had been firing "weakly" too often.
A leakdown test at my favorite mechanic's shop showed that the cylinder with the failed sparkplug was in trouble. When the cylinder head was pulled there was a "dent" in it's exhaust valve's head just about the right size to have been made by the valve banging against that buted off spark plug electrode.
The shop which did the original tuneup had closed, so her daddy got tapped for a $750 valve job so the car would make it through state inspection. He's still cursing whoever screwed up welding the electrode onto that original spark plug's body.
Jeff
My Honda use to be frightening to replace the plugs. They were always tough to remove even after they started to unscrew. The antisieze with Aluminum works better than the copper stuff on them. I replace them every two years or less. I don't blame the mechanic except that he should have known to have that motor hot before he started. I don't think it was cross-threaded.
"Jeff Wisnia" wrote: Don't be TOO sure....(clip) the shop which did the job found that the ground electrode on one plug had disappeared, and installed a new plug at no cost. (clip) ^^^^^^^^^^^^^^^^^^^^ My suggestions were: 1.) Crank the engine to blow air in and out of the spark plug hole. 2.) Blow it out with compressed air. 3.) Clean it out with a vacuum hose. 4.) Fill cylinder with oil and expell the oil by hand cranking.
From what you say, I would NOT do step 1.), because that's where the valve could opened against a piece of debris, trapping it against the inside of the head. (Kind of like what happens when the timing belt breaks on an interference engine.)
I would be very leery about just letting chips blow out the spark plug hole. It may work and it may not. I had a spark plug insulator crack while I was driving the car once, and the chip got caught between the exhaust valve face, and the valve seat. Put a nice big chip in the valve and I had to pull the head to replace the valve. I realize this is a different scenario, but it shows what can happen with a small piece of loose insulator.
You will most likely get all the big pieces out by vacuuming, etc., so you probably won't have anything like this happen. But even small amounts of debris MIGHT get caught on the valve face and COULD result in the valve not sealing properly when closed. Not only that, but some small pieces MIGHT get caught between the piston and the cylinder wall which could yield some nice scratches in your cylinder wall with resulting loss of compression and oil seepage into the combustion chamber.
But if it comes down to a few hundred dollars to pull the head to remove the plug, or just a few dollars to try something else . . .your call. Is the car worth enough to do the job properly, or is it an old beater that you just need to get running for a while?
Just my $.02
Wayne
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