Mayday! Broken Plug Extraction

[Cellnav]

I've got a problem.. Had a water drip near the plug and it was corroded. When I tried to remove it the barrell broke below the nut portion. The barrell is sticking out of the plug hole about 1/4". It's soaking in PB blaster tonight. Any advice what tool to use to extract the remaining portion. Should I use heat? A smart man would have used the PB Blaster before hand.

Aloha

Mike




http://i1201.photobucket.com/albums/bb351/myoungling/photo.jpg

[hanleyclifford]

It would seem that you have a concentric hole to work with which is more than most in this type of situation. Let the PB or Kroil work overnight and then try a large extractor (this is rarely suggested around here). Be prepared to invest in a 14 mm tap or chaser by the time the episode ends.

[Cellnav]

Thanks, I see where this is going :mad: I've already started soaking the head bolts just in case

[Dave Neptune]

Mike, let it soak and tap it lightly with a small hammer, it will help to losten the threads in the hole by breaking down the rust. The threads are seated "UP" from the plug being tightened and the bit og gap will be on the "BOTTOM SIDE". Keep it soaking and a tapping a bit, look carefully around the threads and if you see any movement of the oil or plug it's time for the extractor.

Good luck!
Dave Neptune :cool:

[Carl-T705]

I don't think this is a MAYDAY! From the looks of the plug it was pretty corroded. I think it should come fairly easily, it appears the porcelin did not shatter so if the grounding strap comes out with the rest of the plug you shouldn't have to remove the head to remove debris. I prefer the four cornered extractor over the twisted style ones they seem to grip much better. Heat is always your friend when trying to remove rusted fasteners. Another very old trick is to heat and then sweat parrafin wax into the threaded area much like sweating a pipe joint. people laugh at this, but it has never failed me.

[thatch]

Mike,
Would you mind rolling that plug over a couple of flats and taking another photo of it. I have removed some rusty plugs in my time but never had one fail like that one.
Tom

[Cellnav]

Tom,
NGKs. It failed where they crimp / roll the metal around the tower.

Here's a couple of pics of what's left in the block ( cut an old plug with a Dremel) Should have plenty of metal to work with. It's marinating in PB blaster today and I'll try and get it out as soon as I can make an escape from wrapping paper and endless trips to the store..


http://i1201.photobucket.com/albums/bb351/myoungling/Nub3.jpg
http://i1201.photobucket.com/albums/bb351/myoungling/Nub.jpg
http://i1201.photobucket.com/albums/bb351/myoungling/Nub2.jpg

[thatch]

Mike,
Thank's for going to the extra effort to supply those photos. The secret to removing threaded parts like that, as others have said, lies mainly in soaking them with your favorite penetrating oil and patience. A method that I used to remove the rounded off lower water pump bolt was to use a cold chisel and to try to coax some rotation by taping at it's outer edge at the flattest angle I could, to try to "unwind" it. If you are able to use this method at say 12 oclock and then at 6 oclock, you will be applying a type of "poor man's" impact wrench rather than the slow torque that extractors apply. It will come out eventually, the most important thing is to try avoid any head damage if possible.
Tom

[Cellnav]

After two days of soaking in PB blaster the plug will not budge. Tried heating with a torch, pounding and even ran the engine on 3 to get it up to temp. The easy-out is gripping fine, but I'm bending my 8 inch socket handle and it won't budge!. I'm going to try a longer handle. The next step is drll out the plug. Anyone know what drill and tap size for the plug?

http://i1201.photobucket.com/albums/bb351/myoungling/stud2.jpg

[ndutton]

Just a thought but before you go after it with a drill please consider where the tailings will wind up (inside the cylinder) where they have the likelihood of wreaking further damage.

[hanleyclifford]

In a situation like this I would not try to go directly to the drill size for the tap, which is 14mm. Instead I would ream out carefully with increasingly larger drill sizes until I could clear the threadss with a small pick - then chase the threads with the tap. Of course you are going to have to evacuate the cylinder with a good shop vac and air pressure, used alternately. Hopefully you have a 129 piece drill set.

[jpian0923]

Have you tried twisting it in?

You might be able to use the ground electrode to your advantage. Maybe a screw driver just small enough to fit through the shell to torque against the ground electrode.

If destruction is the only option (last option). You might want to make sure the cylinder is at TDC to make it easier to clean out metal shavings. Also, straighten out the ground electrode so you can strategically place a small magnet on the cylinder head, just below the spark plug hole. This might catch some of the shavings that fall through.

p.s. Good luck!

[Cellnav]

Thanks,
I'm hoping it won't come to drilling. Metal particals are a concern. I've got a shop vac and a magnet ready and will also flush with kero. I thought about pulling the head but I'll have to pull the engine out of the boat - might as well do an overhaul if it comes to that. I'll try a bigger wrench first.

[lat 64]

Thanks,
I'm hoping it won't come to drilling. Metal particals are a concern. I've got a shop vac and a magnet ready and will also flush with kero. I thought about pulling the head but I'll have to pull the engine out of the boat - might as well do an overhaul if it comes to that. I'll try a bigger wrench first.

The bigger wrench will just make it(the easy out) break faster. Don't go there. Tap it like you want to give it a nervous breakdown, but don't force it! it needs to want to come out on it's own. No joke. Heat, oil, tap tap; Heat, oil, tap tap; Heat, oil, tap tap over and over.
Time is what got it stuck, and time is what will get it loose.

[Marian Claire]

Several posts have mentioned the tapping, as in hit, approach to removing the part. I wonder if a small cordless impact driver could be used. Not so much to actually turn the part but just to vibrate it. ???? Dan S/V Marian Claire

[ILikeRust]

1. Kroil (http://www.kanolabs.com/), not PB Blaster

2. Heat. More than you can get with a Bernz-o-Matic propane torch. At the very least, use a MAPP torch. Better yet, acetylene.

3. Cycling, as described above - heat red hot; tap, tap, tap; douse with Kroil; tap, tap, tap; let cool. Heat red hot; tap, tap, tap; douse with Kroil; let cool. Douse with more Kroil. Let sit. Come back later. Heat.... etc.

4. Patience.

It eventually probably will crumble into bits after all that.

[Dave Neptune]

What Russ said and don't twist so hard on the easy-out!!!! the twisting will cause a thin crossection such as what is left in the hole to expand a bit and that just tightens it further :eek:!!!
Patience and a chisle as Thatch described, however tap in both directions, tight very little and loose a lot.
It truly takes "gentle persuasion"!!!

Dave Neptune :cool:

[Cellnav]

Thanks guys. I'll try the subtle approach first. It usually works better with most things. Incidentally, we've named our A4 "Christine" (like the car in the Stephen King novel). It only acts up when my wife's on board..

http://i1201.photobucket.com/albums/bb351/myoungling/christine.jpg

[sastanley]

cellnav, I feel your pain. I am helping a buddy with busted brake lines on an old F-150. We have 4 of the 6 fittings removed, and two stubborn ones that aren't moving yet.

I can also comment that a longer breaker bar won't help either. I had a 4' bar on my tailshaft nut, but it was an impact gun broke it loose in 2 seconds.

[Cellnav]

Put three hours of heating, tapping, oiling and prying without luck. :mad: The plug has become one with the block. I'll try again in the morning.

[sastanley]

Oh sorry...I forgot to tell you...we are on week two. :p (however, in the interest of full disclosure, we have not resorted to heat yet, but I am bringing my torch on the next visit.)

[tenders]

The hole in the middle strikes me as making this more similar to extracting a Cutless bearing than a typical stuck bolt.

My approach at this point would be to stuff a bunch of cotton down the hole to minimize the metal shaving factor. If the cotton is well-packed in the hole, nothing will get into the engine bore.

Once that's done, could you get a hacksaw blade in there vertically? If you can get two vertical, radial slices into the stub in close proximity, close to the threads, you could tap out that small slice of the stub with a chisel, then collapse the rest of the stub away from the threads and draw it all out of the hole. Like cutting out a Cutless bearing, if that makes any sense.

Alternatively, perhaps you could abrade the plug stub from the inside out with a series of Dremel attachments, using a small shop vac to slurp as much of the shavings away from the hole as possible. (This is a less elegant, more "mad dentist" approach than Hanley's 129-bit-kit suggestion above.) As you get more and more of the material out, the stub will have less and less strength, and it'll give up long before you get to the threads.

[edwardc]

Put three hours of heating, tapping, oiling and prying without luck. :mad: The plug has become one with the block. I'll try again in the morning.

It takes time, lots of time, for the penetrants to do their thing. I once had a marine 455 engine with frozen rusted solid manifold bolts. Every day i would come home from work, spray Kroil on them, tap tap tap, heat, cool, more Kroil, tap tap tap. Forward & backward. Took weeks, but they came out. But right up to the point when they started moving, there was NO sign of progress.

The only time I got in trouble was when I got impatient and tried just a LITTLE more force, and sheared off a bolt head. Twice. But after they were all out, and the manifold off, I put a vice-grip on the broken-off stubs and eventually freed them with the same patient routine that would have worked in the first place if I had just stayed the course.

So, don't get discouraged. It WILL come out. Eventually.

[jpian0923]

Here is another approach.

SKlYKG2vyaA

[Cellnav]

http://i1201.photobucket.com/albums/bb351/myoungling/Cut.jpg

Thanks for the support!

I'm considering cutting off the top portion of the plug barrell with a sharp chisel so the threads are flush with the head. The rational is:

1) Relieves the tension on the threads (like removing a bolt head)

2) Allows more direct penitration of the oil into the threads

3) Less chips if I do drill

4) Gives me something to do while the oil does its thing


What do you think?

Happy New Year!



Mike

[ILikeRust]

Gives you less to grab a hold of, though.

[Carl-T705]

I think by removing more material you have less to work with!! What are you heating it with? If it is a propane torch my experience is your wasting time. This type of job calls for Oxy/Acet , heat it red hot and twist out. Some people let it cool before trying to remove, I remove when red.
Sawing a relief groove is also a very good idea, I've done that as well. Saw a relief groove in ,then strike the outside area by the groove with a center punch to drive the section in freeing up the threads and relieving the grip. This would work if you don't have access to a torch. Since you have another plug to look at you can determine how deep to cut without scoring the head threads. Or you could try the center punch hit without the groove for a cleaner operation.
To clean the cylinder out, vacum, then squirt a few ounces of thin oil into the bore place a rag over the hole and spin the starter.

[ndutton]

There are a number of advantages to removing the head:

No more concern over tailings in the cylinder, opens up drilling options. If drilling, know that there are left hand drill bits available.
You can work from the underside if you desire. A right hand drill bit from underneath puts forces in the direction you want too.
Having an engine shop perform the extraction becomes available.
As long as the head's off, cleaning up the coolant passages can be done.
Heaven forbid and I apologize for even mentioning it but if the head becomes damaged with this exercise you'll be removing it anyway. Why not sooner than later?

I agree with the rest that patience is a virtue but there comes a time, y'know? I can't say I'd have the restraint you've already shown.

[Cellnav]

I'm heating with MAP Gas.

NDUTTON, you're right, I should pull the head. I've got family in from the mainland right now and being in Hawaii, we're still (literally) sailing the boat. I know if I pull the engine I'll find more than a stuck plug. I won't stop until it's overhauled.. If it's not out by MLK weekend - "I have a dream"..

Aloha,

Mike

[67c&ccorv]

I think by removing more material you have less to work with!! What are you heating it with? If it is a propane torch my experience is your wasting time. This type of job calls for Oxy/Acet , heat it red hot and twist out. Some people let it cool before trying to remove, I remove when red.
Sawing a relief groove is also a very good idea, I've done that as well. Saw a relief groove in ,then strike the outside area by the groove with a center punch to drive the section in freeing up the threads and relieving the grip. This would work if you don't have access to a torch. Since you have another plug to look at you can determine how deep to cut without scoring the head threads. Or you could try the center punch hit without the groove for a cleaner operation.
To clean the cylinder out, vacum, then squirt a few ounces of thin oil into the bore place a rag over the hole and spin the starter.

In all of the resposes in this thread that mention heating...no one has mentioned what part you are directing the heat to?

You want to heat the head around the broken thread - not the broken thread itself. The idea being to cause the threads around the broken plug to expand faster than the broken half of the plug.

In fact, I would go so far as to heat the head around the busted thread and then apply some ice packed in a small diameter container that would help to cause the threaded portion to contract while the head portion is still hot and expanding.

Good luck!

;)

[sastanley]

cell...in that case, run it on 3 cylinders if you don't solve it by family sailing time. :rolleyes:

Yanking the head is only gonna cost a head gasket.

[Dromo]

let me see if i'm understanding this . you have a broken spark plug, the bottom of the plug is still in the head, which i would think is the same as no plug and gas would be spraying out of the cylinder head into the engine compartment when it is running and your still running it?
Rick

[sastanley]

Oops...Dromo...you might be right...I forgot the middle of the plug came out! :eek:

[ndutton]

I don't think gas is a problem. If the bottom of the spark plug is still intact it will seal off the cylinder, if the plug carcass is clear through there will be no vacuum in that cylinder and therefore no way for the fuel/air mix to be drawn in.

Remember, we're not injected, carbureted intakes suck.

[jpian0923]

Duct tape the hole. Trying to be helpful...

[Dromo]

I removed 1 spark plug last spring due to it not firing ,turned out to be water getting in the one cylinder form the head gasket. anyways i wasnt thinking and started the engine to diagnose the problem and when I went to have a look Gas was spraying out of the spark-plug hole in the form of droplets .I didnt think I could move that fast to shut it down. I hope the bottom of the plug is still intact but if you look at Mick's 1st pic you can see the spark plug electrode
Rick

[Carl-T705]

I would disagree on heating the head, I would heat the broken plug, the point being to soften the threads on the plug to where they lose their grip on the head. By heating the head you may end up removing the threads on the head. The plug remains being hollow and less dense would heat up very quickly.
I doubt any penetrating oil has gone past the metal sealing gasket and has reached the threads yet. I would try blows with a hammer and punch to the sides of the remains before pulling the cylinder head if heat is not an option.
If you chose to run it on 3 cylinders for an outing you could drive a short piece of wood into the hole and a short metal strap from one head bolt to another across the wood peg to hold it in place or drill a hole in the wood plug and safety wire it down. Don't drive the plug in so far as to interfere with the valve movement... or break off the grounding strap!!

[Cellnav]

Aloha all,
I'm happy to report the plug is out! Went out yesterday and heated the plug (which had been swimming in Acetone and ATF) for about 5 min with the Map tourch. Tugged on the plug while hot and it didn't budge. Quenched it with PB Blaster and went for broke with the long socket driver. It came out with a loud groan. The plug was only rusted around the sealing ring and the top quarter of the threads. I sucked out the cylinder and used a magnet on a wire and found a couple of rust chips that had fallen in. Ran the engine with the plug out for a minute (with all hatches open and blower on) to blow out the stragglers. The A4 is sounds like a sewing machine, but is running hotter since "the tune up". This whole saga started with crank no spark. I may have some invertebrate critters squatting in my cooling system (time for acid flush), but could ignition timing cause hot running?

Thanks for all your sugestions and support

Mike

[67c&ccorv]

I would disagree on heating the head, I would heat the broken plug, the point being to soften the threads on the plug to where they lose their grip on the head. By heating the head you may end up removing the threads on the head. The plug remains being hollow and less dense would heat up very quickly.
I doubt any penetrating oil has gone past the metal sealing gasket and has reached the threads yet. I would try blows with a hammer and punch to the sides of the remains before pulling the cylinder head if heat is not an option.
If you chose to run it on 3 cylinders for an outing you could drive a short piece of wood into the hole and a short metal strap from one head bolt to another across the wood peg to hold it in place or drill a hole in the wood plug and safety wire it down. Don't drive the plug in so far as to interfere with the valve movement... or break off the grounding strap!!


Have you ever seen a valve guide removal torch? It heats the head around the guide without heating the guide itself - again to cause the head surrounding the guide to expand while the guide itself expands at a slower rate.

Methinks this problem is roughly the same...in fact, I would argue in the thread below that the squirting of PB Blaster acted as a coolant and caused the broken plug thread to contract slightly allowing it to come free.

;)

[67c&ccorv]

Aloha all,
I'm happy to report the plug is out! Went out yesterday and heated the plug (which had been swimming in Acetone and ATF) for about 5 min with the Map tourch. Tugged on the plug while hot and it didn't budge. Quenched it with PB Blaster and went for broke with the long socket driver. It came out with a loud groan. The plug was only rusted around the sealing ring and the top quarter of the threads. I sucked out the cylinder and used a magnet on a wire and found a couple of rust chips that had fallen in. Ran the engine with the plug out for a minute (with all hatches open and blower on) to blow out the stragglers. The A4 is sounds like a sewing machine, but is running hotter since "the tune up". This whole saga started with crank no spark. I may have some invertebrate critters squatting in my cooling system (time for acid flush), but could ignition timing cause hot running?

Thanks for all your sugestions and support

Mike


Heating the broken plug thread only causes it to expand further into the threaded portion of the head.

I think by quenching the plug thread with PB Blaster you caused it to contract and thats what loosened it.

:)

[Carl-T705]

Actually no, I've never seen a valve guide removal torch. Until now I've never heard of one. But I would be very disappointed with my engine man if I ever caught him putting the torch to any of my cylinder heads to remove a valve guide.
I would think the long breaker bar had more influence than a shot of PB!

[67c&ccorv]

Actually no, I've never seen a valve guide removal torch. Until now I've never heard of one. But I would be very disappointed with my engine man if I ever caught him putting the torch to any of my cylinder heads to remove a valve guide.
I would think the long breaker bar had more influence than a shot of PB!

Then you haven't worked on British motorcycles...I'll see if I can find a pic and post it up.

:D

[jpian0923]

Are you having an overheating problem also?
What temps are you seeing after warm up?
The issues are not likely related.
Tell us more.

[Carl-T705]

British Motorcycles???? Well that explains it!! LOL ! I thought they call them motorbikes?? I had a 70 BSA, back in the early 70s, it came with a couple of wrenches, pliers and a screw driver. Hope you can find a picture.

[Cellnav]

Temp starts at 160 in idle and slowly climbs to 180 under power. I'm pulling it back when I see steam coming out the exhaust. I'm getting reasonable water flow out the exhuast. Also getting that "I'm hot" smell in the cabin. I cleaned the water intake without much improvement. I'll look at the impeller/the pump next. I rebuilt the Moyer aftermarket pump last spring and replaced the thermostat a couple of years ago.

[Dave Neptune]

Mike, good to see persistance and patience won out in the end.
Fair winds. _/) _/)

Dave Neptune :cool:

[Carl-T705]

I'm no expert, but my understanding is with steam coming out the exhaust you need to restrict the bypass flow of water. That would be the hose coming from the water jacket inspection cover on the side of the block leading to the top of the thermostat housing. If the hose is real pliable try squeezing it down with visegrips or a clamp and run the engine through some test runs. Most put a inline valve in this hose to fine tune temp.

[Maurice]

Hi,

Are you running with a thermostat. If so, remove it and see what happens. If you have a by-valve leave it open at 1/2 and see how it goes. If that doesn't work, go for the impeller. If it failed (pieces missing etc) also check for a blockage in the elbows as you trace the hose in toward the engine.

My first guess is T-stat. I don't use them....to me they are head gasket haters. I'd almost bet my right one that I've seen your problem at least six times on other boats...and is exactly why it (t-stat) was deep sixed. If you don't have a by-valve just remove the T-stat and replace with a bit of silicone for a gaskets if yours is worn. Order up by-valve from MMI and a gasket and install all when you get the by-valve.

[Cellnav]

I am running a themostat. If I install the valve do I have to close it until I'm up to temp then open it after warm up? I'm concerned I'll forget to open the bloody thing.

Aloha,

Mike

[hanleyclifford]

I am running a themostat. If I install the valve do I have to close it until I'm up to temp then open it after warm up? I'm concerned I'll forget to open the bloody thing.

Aloha,

Mike The bypass shut off valve should be in the wide open position at starting. It should only be closed (and in small increments) if the engine temp rises above your desired level.

[Carl-T705]

Maurice, I have a question, If you don't run a thermostat, do you run any kind of a restrictor plate? I think that in order for the coolant to travel through the block and pass thru all the passages it, the water, would have to be slightly pressurized and the flow slowed down otherwise it will simply take the path of least resistance which would be into the block and out the thermostat housing.
On my race engines they actually run cooler than having no thermostat when I take a thermostat, clip the two tangs and remove the actual heat control and spring, I then beat the curved lip flat to make the center hole even smaller and then install them. which is basicly a restrictor at this point.

[Maurice]

Hi Carl,
The by-valve, inserted in the line just prior to the T-stat, is your restricter. This is very simple and ensures that water gets to the head. I just leave my by-valve open 1/2 here in Nova Scotia and the engine runs really good. This leaves a bit of back pressure and forces water through the block. Carb is leaned out and I'll attach a pick of the plugs.

When I head outside the harbor there's nothing but water between me and Europe. Most times I can sail, however, there are times I have to motor. Usually when motoring the seas are calm, however, we do have one area called Sambro Ledges. In this area the sea runs into relatively shallow area ... 60 to 80 ft generally. Our summer winds run SW for the most part so it's often that I'll have to motor through those ledges with wind and sea on the nose. The waves can be mountainous there and full throttle required to keep way on. 15 to 20 kts of wind will give you a ride. Not a time to lose the engine. It's about 7.2 nm long....the red line in the pic below.

I cannot justify a T-stat because the ocean is my rad. I am not holding back water to be cooled in a radiator (raw water cooled). My main concern is having a T-stat malfunction when running the engine hard. I didn't dream this up, another guy told me about it when I first got the boat. Thing is I sail min 1000 nm per year and the motor will be called upon. If I fall prey to overheating in a sea it will be due to blockage at intake, impeller failure or pump failure. But I really think I did eliminate one possible failure...T-stat.

EDIT 1: The yellow pegs along the shore are places we take off to for the weekend. They are all day sails, some shorter, a few longer. As you can see, there are loads of places to duck in but the shallows, reefs, rocks and the like make some spots more difficult to get into.

[Carl-T705]

Thanks Maurice, I went back and read your earlier post again, Oddly I was under the assumption your were not running a valve / restrictor in your bypass line. From the looks of your plugs that is a clean burning A4, You have perfected carb tuning. Let me also ask this, since your RWC in salt water have you introduced a sacrificial zinc anywhere in the cooling system?

[Maurice]

Hi Carl,
No anode in the cooling system. Only 2 on the prop shaft...