FITZ Posted July 31, 2006 Share Posted July 31, 2006 Snapped Spark Plug - Any Tips?? I was 'helping' my son service his first car, an old fiesta that we had recently bought. It was obvious that it had not been serviced in a long while and the spark plugs were surrounded by rust. We blew out the loose rust and soaked the plugs in WD40. Three came out, they were all very tight but with half a turn out and a quater back they came out but the forth plug would not move. I suggest we took it for a run and the plug may move with the engine hot. When I tried again but the plug snapped off clean with the block I'm reluctant to try a thread removal tool as the plugs were so tight I think it would just snap. So the question is any tips for removing the remaing part of the plug? Quote Link to comment Share on other sites More sharing options...
minivin Posted July 31, 2006 Share Posted July 31, 2006 no easy method unfortunately from what I cn think of, personally I'd remove the head, drill down the centre to the core diameter of the thread to remove as much of the plug as possible and then tease the last of the plug out of the threads Quote Link to comment Share on other sites More sharing options...
Les Henson Posted July 31, 2006 Share Posted July 31, 2006 Old Fiesta's are 10 a penny now. You would probably get one for about £30 from a scrappy. Les. Quote Link to comment Share on other sites More sharing options...
FITZ Posted July 31, 2006 Author Share Posted July 31, 2006 Thanks for the replies, I'll have a look tonight and see if anything spings to mind other than taking the head off which as you pont out maybe the only option. Quote Link to comment Share on other sites More sharing options...
02GF74 Posted July 31, 2006 Share Posted July 31, 2006 I'm reluctant to try a thread removal tool as the plugs were so tight I think it would just snap. So the question is any tips for removing the remaing part of the plug? you're right there - all that would happen is you would then have to remove a hardened steel snapped off extractor it may be possible to use a hack saw and saw into the side to weaken the threads grip but you would need to remove the ceramic core - that will leave debris in the cylinder so heads off I'm afaraid (unless you attach a tube to a powerul vacumm cleaner?) Is it early festa with crossflow engine? I have a brand Ford new x-flow head, make ma an offer I cannot refuse and it is yours. Quote Link to comment Share on other sites More sharing options...
Diff Posted July 31, 2006 Share Posted July 31, 2006 Thanks for the replies, I'll have a look tonight and see if anything spings to mind other than taking the head off which as you pont out maybe the only option. If it has snapped off, has any of the centre of the plug fallen into the engine?. If not, you could try welding a bolt or nut to what remains of the plug. The heat from welding may be enough to free it, to enable it to be removed with a socket on the nut/bolt that you have welded on. If the plug is in a deep recess, this will be impossible obviously. Regards, Diff Quote Link to comment Share on other sites More sharing options...
jjojjas Posted July 31, 2006 Share Posted July 31, 2006 I'm with Les on this. I have removed a snaped plug from a volvo head and it was a pain in the butt. If I had known at the start that I could have a 2nd hand head for £40 I'd have changed it instead. Jas Quote Link to comment Share on other sites More sharing options...
Andy Posted July 31, 2006 Share Posted July 31, 2006 this is why proper engines are compression ignition *hides from the V8 crowd* Quote Link to comment Share on other sites More sharing options...
FITZ Posted August 1, 2006 Author Share Posted August 1, 2006 Update. After 2 hours I manage to drill out the plug and remove the remains of the plug thread from the head. Before I started I moved the piston to the top of it's stroke and filled the bore with grease, that allowed me to retrive the swarf with a magnetic screwdriver. I drilled very slowly and removed the swarf before it got to hot and melted the grease. I managed to get most of the grease out though the plug hole with a scew driver some small ceramic pices came out with the grease. Next step is to clean the thread up and get a 10mm tube on the end of the aquavac to remove any ceramic debries. Fingers crossed and may get away with it. Thanks for all the replies and suggestions. Quote Link to comment Share on other sites More sharing options...
02GF74 Posted August 1, 2006 Share Posted August 1, 2006 Update.After 2 hours I manage to drill out the plug and remove the remains of the plug thread from the head. Before I started I moved the piston to the top of it's stroke and filled the bore with grease, that allowed me to retrive the swarf with a magnetic screwdriver. I drilled very slowly and removed the swarf before it got to hot and melted the grease. I managed to get most of the grease out though the plug hole with a scew driver some small ceramic pices came out with the grease. Next step is to clean the thread up and get a 10mm tube on the end of the aquavac to remove any ceramic debries. Fingers crossed and may get away with it. Thanks for all the replies and suggestions. [monty python voice on]You clevere b******rd!! like the grease idea; you could have put piston half way down (or half way up, whichever was easier ), fill with greasthe put to TDC - that would ensure all chamber was full. to get bits out, put piston at TDC where exhaust is open, force paraffin (not sure how?) via the plug hole to flush bits out via the exhaust. you might get away, just make sure you are far away from those meddling kids! Quote Link to comment Share on other sites More sharing options...
MogLite Posted August 1, 2006 Share Posted August 1, 2006 Before I started I moved the piston to the top of it's stroke and filled the bore with grease.... How did you manage to do that with a bust spark plug in the head ? Quote Link to comment Share on other sites More sharing options...
FITZ Posted August 2, 2006 Author Share Posted August 2, 2006 How did you manage to do that with a bust spark plug in the head ? When it snapped it only left the threaded part of the plug in the head. the hole in the middle allowed me to use the grease gun to fill the cylinder. Update I invested in a Sealey 'spark plug thread chasing tool' only £8 at a local car spares shop (about £6 on ebay plus P&P if you want one). This was excellent at cleaning up the damaged thread in the head ( damaged by me getting the remnants of the spark plug thread out with a small scew driver). I did a final vacuum of the cylinder and a search for the last of any swarf with a magnetic screwdriver. Put the new plug in (with copper slip) a bob your uncle she's a good un. Quote Link to comment Share on other sites More sharing options...
jjojjas Posted August 2, 2006 Share Posted August 2, 2006 top marks mate. Were you in the "A" team? Jas Quote Link to comment Share on other sites More sharing options...
imspanners Posted August 5, 2006 Share Posted August 5, 2006 Sorry for the late reply, and if it helps somebody else, you probably wont want to hear this, but having worked for Ford a few years ago. The easiest way to remove a broken spark plug: Disconnect coil, spin engine over on starter to blow out remaining ceramic left in plug base. Looking inside the plug you'll see the shape is hexagonal, but an allen-key won't work. Using a torx socket, a TX55 to be precise. Hammer it into the inside of spark-plug. Undo using 1/2" breaker bar and suitable extension, making sure you keep the extension perpendicular to the plug. If severly tight, get some-one to tap the top of the breaker bar whilst you turn it to jolt the seized threads. That has never failed to remove a broken spark plug. B) Quote Link to comment Share on other sites More sharing options...
Phil Platts Posted July 14, 2009 Share Posted July 14, 2009 I am not very mechanically minded at all but I sent my Morris Minor for service and the garage did a great job but told me they couldn't remove one of the plugs and they thought it was cross threaded. I decided as did the originator of this thread to try to do it myself after getting the engine hot, but just as his did the plug, after tantalizingly coming out a couple of threads, then snapped off. I read this thread which I found through Google and found it helpful. However I must tell imspanners (Aug 5th 2006) that I want to enter my stuck spark plug as the most stuck spark plug of all time. No-one who tried could get it to budge with the TX45 (which seemed the right size for a Morris Minor) or a TX50 or anything else. They just cut through the inside of the stuck plug. Perhaps because I am so naive mechanically I decided to disagree with all the others who told me the head would have to come off. I just couldn't see how the plug could possibly stay in there if I used a hacksaw to cut two grooves through the inside of the plug - it would HAVE to come out wouldn't it? So I followed the first step which was to chuck an old sweater over the plugs and fire the engine on 3 cylinders and was amazed when all the ceramic blew out just as they said it would - it almost blew the old sweater out of the bonnet! That left a nice clean hole. I removed the washer from the old spark plug which was still sitting there and after the above methods had failed as stated I set about sawing 2 grooves using a Padsaw handle fitted with a junior hacksaw blade (any other blade was too big). You need to keep the exposed blade short as it will tend to snap off in bits. Before doing this I took off the valve cover (easy, just 2 bolts) and ensured the rockers were up (I was told this means they are in the closed position and this means bits of metal won't fall inside the piston bore). Then I sawed the grooves into the shell of the old spark plug. Finally I used an old screwdriver and a hammer to knock the wall of the old plug inwards then knocked it back out and back in again etc to weaken it and hey presto the last step was to use a pair of long necked pliers and I screwed the pesky thing out. My neighbour lent me a spark plug device which I think he called a chaser, which is like a spark plug with grooves in the thread and this is screwed into the hole bit by bit to clean the thread in the head. Last step was to use a small magnet-tipped screwdriver to poke down the hole several times and bring up one bit of broken hacksaw blade and lots of iron filings. The new plug went straight in and the car is fine. I don't want to give the impression I did everything on a wing and a prayer as I asked the opinion of 2 mechanics and neither of them baulked at the idea, just counselling to be careful - which I was. I hope this helps anyone with the same problem - if I can do it with almost no knowledge of car mechanics (but a reasonable brain I hope ) then anyone can. Quote Link to comment Share on other sites More sharing options...
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