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i have a y reg 1300 ohv fiesta i have only had it a month when i went to change the plugs were rusted in as the socket will not fit on the plug with that much build up of rust i think they must have not been changed for a few years. I cleaned a load of rust away and used penetrating oil but when i tried to take them out 2 snapped all that was left in the head was the thread off both plugs can i use a easy out or anything else as i do not want to take the head off any help please
Edited by Pugugly {P} on 27/01/2008 at 21:33
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Wecome to the Back Room.
Don't worry you're not alone - see www.honestjohn.co.uk/forum/post/index.htm?t=46588&...f
I particularly like Screwloose's suggestion, especially you're now at this stage.
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Screwloose suggestion spot on, works every time . I have done many that way.
Doc
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I've been working on a Ford Ka this weekend, got one spark plug out but couldnt shift the others. This is the second overnight soaking in plusgas so I'll try again today and at least I feel better about possibly breaking them now that I've read this post. I had been thinking of hiring an electric pipe freezer and clipping it onto the sparkplug socket to shrink the sparkplug a bit but I think I'll try the suggestion from screwloose about using a Torx bit if I need to.
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Well I broke two of the plugs, a clean break just above the surface of the engine. First thing I did was to find a plastic stopper for the end of my vacuum cleaner, drill a hole in it and insert a length of clear plastic tubing (diameter just a bit less than the spark plug hole) so I could vacuum up the broken bits as I went along. Then with a hacksaw I cut one of the unbroken spark plugs at exactly the same place where the others had broken. First thing I noticed was that there is a shoulder half way down inside the plug body which means the the ceramic insulator and centre electrode cannot be pushed down into the cylinder. In my cut-open plug the broken bit of ceramic left inside the plug fell out as soon as I turned it upside down so I hoped the ones in the engine might be blown out if I turned the engine over on the starter but they didnt come out. So I used a small masonary drill on the surface of the ceramic and also chipped away with a little spike whilst hoovering up the bits. Eventually I had just enough of the electrode showing to grip it with a pair of long nose pliers and lifted it out quite easily. In the other case the ceramic and the electrode came out on the end of my plastic hose when I was chipping and hoovering away. So in each case I dont think anything can have fallen into the cylinder itself.
I do have a size 55 Torx bit but I also have a Sykes Pickavant extractor set and one of the bits is exactly tho right diameter to be hammered into the spark plug as far down as the shoulder. This bit has flutes down the side that cut slightly into the inner diameter of the spark plug in way of the outer thread.
However the next stage has not worked out so far. In spite of another soaking with plusgas and putting a two foot breaker bar on the extractor I havent managed to turn it. The extractor is not slipping so I may have to use a 3 foot bar but meanwhile I'm having a cup of tea whilst I think about ways of applying some heat (or cold) to the plug socket without heating up the surrounding engine.
I'll let you know what happens.
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Go carefully and take your time. Don't be tempted to heave on the extractor just that little bit more if you think you are near its break point - a sheared extractor is a complication you could well do without.
It's worth reflecting that all this misery has been caused by some idiot bean counter at FMC who probably won a bonus one year for eliminating four crush washers and deleting the nickel plating on the plug bodies.
I used to work for a Company which supplied Ford and remember similar constraints such as being told to delete a washer on the output terminal of a heavy duty alternator - price to be adjusted accordingly. I have never been a customer of FMC since - I put that washer there for a reason.
Best of luck - hope you come back eventually with some good news. A can of electronic engineer's freezer spray could help.
659.
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could you not run the engine up on the remaing good cylinders to heat up the head...and maybe a blast of that pipe freezer aerosol?
the heat from running it might let some penetrating oil soak down
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You may well end up finishing of the DIS unit using this method.
Dont use a stud extractor, if it shears you can't drill them out. It works fine with a torq bit or a spline tool. just hammer a spline tool in & undo, as i said in my last thread I have used this
process for years & never had to remove a head yet.
Doc
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Hi Doc
I'm not using a stud extractor, I'm using a spline tool. Its made by Sykes Pickavant so its top quality, in fact I've been surprised how much torque I've been able to exert without it slipping or breaking. Fact is I think my plugs are much more stuck in than normal. In other words I wish I was in your position and could use your tried and tested solution but, unfortunately for me, it seems I cannot.
I really appreciate everyone's advice, I've owned Fiestas with these engines for some years and never had this problem. I've always realised it COULD be a problem but I've avoided it by removing the plugs every 12 months and also by not over tightening. The recommended 15-20 Nm is easily exceeded when using a normal socket set/plug spanner. This particular vehicle I'm helping with (owned by a colleague) has main Ford dealership service history but they have certainly overtightened the sparkplugs in the past.
This afternoon I tried a heating approach. Put a rod of aluminium (becuse I didnt have
a copper one) pressed into the open plug hole and heated up with a Ronson gas torch. The remains of the sparkplug were heated up to about 100 centigrade and I hoped the differential expansion might break the rust out when the plug eventually cooled down.
Didnt work.
I'll tackle it again tomorrow after thinking overnight. Maybe freezing the remains of the socket would work. I'm very familar with plumbers freezing spray and have had some hairy moments using it. Anyway cant afford to have freezing spray running into the plug hole so I would use a purpose built electric freezer unit. £77 hire a day from HSS but maybe I could justify it by a couple of outstanding plumbing jobs. (Like replacing a motorised valve I should have done 3 years ago).
I've got a MIG welder but I'm just a bit reluctant to use such an all-or-nothing approach. If it went wrong I'd be looking at removing the cylinder head so I might as well try all the other possibilities first. I'm disappointed that the straightforward solutions recommended by others havn't worked for me so far. I envy them because I've got better things to do than fiddle around with the insides of broken spark plugs. But I
'm grateful for all helpful advice.
I'll let you know what happens.
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On my sister's car, once we'd (carefully) folded the taper seat in on itself using a sharp chisel, the thread came undone relatively easily by smacking a large screwdriver into the centre of the hole (thus pulling the taper away even further) and using molegrips to turn the shaft. It seemed to be the taper that had seized to the head rather than the threads. Once it moved even slightly, we could unscrew it using finger and thumb pressure.
Another plug snapped in service just before Christmas. My dad got that out in about two hours using the same method as before. Careful drilling to enlarge the hole as close as we could (use a new plug to judge bit size), then folding over, screwdriver in, and turn.
The hard bit then was getting the swarf out of the cylinder. This was done with a vacuum cleaner, a length of fuel hose, and some gaffa tape. Probably not 100% effective, but the engine ran fine afterwards so we got away with it.
It's a horrible, nerve wracking job. Best of luck with it.
Cheers
DP
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Success, I finally got both the plugs out today.
I didnt want to use a mig welder in case it prejudiced any subsequent machining if I had to send the cylinder head away and for the same reason I was a bit wary of just hammering the top of the plug inwards though that has clearly worked for others. My local garage normally do this but told me that had had two or three engines where it hadnt worked and they had to take the head off. So here is my slightly more cautious method.
- Make up a vacuum hose small enough to go down the spark plug hole. I put a rubber plug into my normal vacuum cleaner hose, drilled a hole in it and inserted a length of clear plastic piping.
- Use a small masonary drill and a sharp pick to chip away at the ceramic insulator in the broken sparkplug. I tried turning the engine over to see if it would blow out the ceramic insulator but that didnt work for either plug. On the other hand, as soon as I had chipped away enough to expose the electrode I was able to grip that with a pair of long nose pliers and lift the electrode and the ceramic out in one go. In the case of the other plug I had to chip away much further until I got down to the inner shoulder at which point I was able to draw out the electrode and the last bit of the ceramic dropped down to be held by the earth electrode. So no bits fell into the cylinder but I was careful to use the vacuum after every bit of chipping.
- Put a small twist of tissue down the open plug until it rests on the earth electrode so nothing else can fall down. (If the tissue should fall into the cylinder it will be burnt up anyway).
- Take a 12.5mm drill and drill down into the sparkplug a distance of about 9mm but definitely not more than 10mm. This measurement is from the surface of the broken plug to the cutting edge of the drill, NOT the point of the drill. (Make up a rod with a sliding cable tie to act as a depth gauge). Drill a bit and then measure the depth and so on. I cleared swarf with the vacuum cleaner but also magnetised a 6 inch nail in order to lift swarf off the tissue paper at the bottom of the plug hole.
- the purpose of this drilling is to ensure that the upper part of the broken plug is thin-walled down to a point just BELOW where the plug seats into the cylinder. The 12.5mm diameter means that the drill will remain inside the plug body and will not break out and risk damaging the seating area of the cylinder head. The depth of 9mm ensures that the hole is drilled below the level of the seat but stops just above the threaded part of the plugs. The result is that the wall of the plug at this point is now only about half a millimetre thick.
- Then take a narrow cold chisel/punch/drift etc and bend the top of the plug body inwards. Its very restricted but I found as soon as I had got a bit of each side bent inwards and slightly opened from the surrounding cylinder head the whole of the top half of the plug broke away at the thin walled part just above the thread which I mentioned above, and could be lifted out.
- I removed the thread part of one plug by just sticking a srewdriver down it and turning by hand. The other one was more stubborn and because of the previous drill out and the fact that the upper part has just been broken out, there is very little depth in the plug body before the internal shoulder narrows the internal diameter. I took an 8.5mm drill and drilled out the shoulder to a point just above the piece of tissue paper. This was enough clear depth to hammer in my extractor and then the screwed part came out straight away, including the bit of tissue paper with one or two bits of swarf on it.
- With a fibre optic cable I checked the inside of the cylinders for any other swarf or debris but there was none to be seen.
So the final result worked out well and thanks for everybodys suggestions. I hope my tips will be useful for someone in the future.
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Claude, congratulations on your success - the broken plug problem happened to my SiL's Fiesta some years ago and, iirc, she took it into the garage to sort out.
I am intrigued to know about this fibre-optic cable. Can you tell me more about it , please, where did you get it from, how much it cost etc?
Thanks, Waino.
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Nice one!!
Then take a narrow cold chisel/punch/drift etc and bend the top of the plug body inwards. Its very restricted but I found as soon as I had got a bit of each side bent inwards and slightly opened from the surrounding cylinder head the whole of the top half of the plug broke away at the thin walled part just above the thread which I mentioned above, and could be lifted out.
It's this part that looked like it was causing the problem on ours, not the thread itself. as I said, once we'd bent this bit inwards, the threads came out with hand pressure.
So glad you got it sorted!
Wind the plugs out and refit them every 6 months and you shouldn't have another problem.
Cheers
DP
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ive always fitted the plugs with a bit of copper slip on them and never had any problems
chris
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Me too. Seems so obvious, but I guess garages and manufacturers can't be bothered.
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Thanks for your support guys. I agree a little bit of copper slip on the plug landing (not the threads to avoid overtightening) must be a good preventative measure.
Regarding the fibre optic cable. Maybe I made it sound more sophisticated than it really is. It consists of a small rubber cup which fits over a Maglite (the size that uses two AA batteries) and about 10 inches of rubber covered fibre optic cable about the same diameter as the inside tube of a Biro pen, but more flexible. When you stick the cable down into the clyinder head it lights up the interior which therefore makes it much easier to see when looking down into the sparkplug hole compared to shining a light in from outside.
I bought it in an accessory shop about 5 years but I cant remember where. Seemed like a good idea at the time (ie a boy's toy!) but realistically I've only had a use for it on a couple of occasions. This time it was actually rather useful.
Having said that I have seen medical and industrial fibre optic technology which allows you to actually look down the tube itself and also steer the direction of the bottom end of the tube. They start at several hundred pounds but I guess the technology will inevitably trickle down to other applications and become cheaper.
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>>I agree a little bit of copper slip on the plug landing (not the threads to avoid overtightening) must be a good preventative measure.
Actually, as the seal surface is at a larger radius than the threads, applying copperslip there has a larger effect on how much pre-load is obtained per unit torque than if you copperslip the threads.
Practically, using copperslip on these is an excellent idea - the nightmare of removing snapped plugs is an all too common occurrence. But, if the torque figure given in the spec is for a dry plug, then it might be best to reduce the torque applied if copperslip is applied.
Having said this, I don't think there's actually much danger of overstressing the plug if dry torque figures are used with a copperslipped plug - the torque figures are typically not particularly high - I've never seen one snap, and I'm an adherent to the policy of using copperslip myself.
Number_Cruncher
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Thanks for the note re: the fibre-optic cable, Claude. I do have some experience of fibre-optics, but they were wielded by a surgeon, and I was 'asleep' at the time! I thought, from your note, that there might be a cheaper 'cruder' version available for use on a car's innards.
To be honest, the use I have in mind is for looking into a blanked-off space under the stairs. I suspect there's an opportunity there to build in a cupboard but I thought it might be a good idea to make a small exploratory hole and check for the number/location of structural supports before tearing into the job.
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