Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Spark plug removal

Any advice and guidance on removing an extremely tight spark plug in the GDI engine?

Have tried running the engine to heat up and applying easing oil to no avail.

Could I break the spark plug if I use my breaker bar with 16mm socket?

Or is a wack with a lump hammer and stiff bar a better solution?

Collective ideas appreciated.

Chris

As much as I hate answers that start with it depends it really does depend on the quality of your spark plug socket and what is essential is that it has a rubber insert. If that’s the type that you have then there is no problem using a knuckle bar but the damage occurs when the extension between the socket and the knuckle bar is not held absolutely square to the spark plug. Any force that puts any sideload will shatter the ceramic without fail in fact it’s not a bad idea to have a spare spark plug handy as the threads may well be stretched if it’s been overtightened and I would recommend fitting a new plug afterwards.

You might be tempted to put your breaker bar/knuckle bar directly onto the socket but don’t do this it’s much easier to keep everything square and in line if you use an extension on the socket and put your knuckle bar onto that.

Under no circumstances should you ever use any kind of impact and I hope that part was tongue in cheek as that’s a guaranteed way of damaging the ceramic insulator of the spark plug.

No point at this stage going into why it’s been overtightened in the head as unless it’s been filled with water and left for a long time that’s almost certainly what’s happened many people have no idea how little these plugs should be tightened up. They really are finger tight and a slight nip afterwards they don’t come loose, they don’t blow out, that’s just an Internet myth and old wives tales,

Good luck!

BR
Colin

I'd be a trifle worried about the condition of the threads in the ally head. Just my old BMW airhead boxer thinking

One of the advantages of the conical head plug Graham is they tend to bite into the seat and lock up before the head thread is destroyed, never seen a conical plug rip the thread out of the cylinder head but seen quite a few of the old crush washer type that did it.

BR
Colin

Just in case water has got into the plug area it would not be a bad idea to fill the cavity with wd40 or similar and let it sit there overnight so it might percolate down the threads a bit. I know it's a bit late for you but with all new cars (including my GDI)
I remove the plugs as soon as I get them and re-fit with the threads lubricated with ultra high temp ceramic grease (better than Copperslip). Good luck.

Spanner juggler is bang on with his advice, as always.
In addition, I would always plop a vacuum cleaner hose over the plug recess prior to removal, to suck up any loose
debris that may fall into the cylinder.
Recommended torque is 10 to 20 Nm, which ain’t a lot!
Removal at least once a year should reduce the issue. Due to the longevity of plug electrodes, I am not convinced that all dealers do this on an annual service! ( despite what you pay them!)

Use ... Shock spray...from Innotec. Spray 10 / 15 sec . on the spark plug , than untighten the spark plug and clean the spark plug hole before taking out the spark plug. It REALY works

Stefan

Thanks guys.

Some really great ideas there. Water has got onto plug 1. The others came out easily and were replaced with new.

The replacement plug package says 10 - 15 foot pounds tightening torque ie not a lot.

Job for next weekend!

Chris

In the interim Chris give the plug surrounding area a good soak with release spray. Then before you try and remove it push a thin strip of soft cloth down there to soak up as much as you can as your catalyser won’t like being covered by the stuff!

BR
Colin (if you have a compressor and air gun or even an aerosol of air from a camera shop to blow around the plug to clean out debris it’s a good idea before you try and remove the plug).

👍👍👍