Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Spark plug stuck....

I'm trying to remove the plugs from a 2l Mazda/Duratec engined +4SS. The first one I tried (No 1) seemed pretty stubborn. Before I attacked it with more brute force, has anyone got any tips for making the task easier? Engine hot or cold? Penetrating oil first? Plugs were removed last year for checking btw.
Regards, Nick

We had the sa,e problem yesterday on my plus 4, wd40 liberally applied and gentle but firm spanner work

Cold engine

Try and clean out the plug recess first with air if possible,quarter turn spray a nd leave for 5 mins sometimes the plug actually tightens as you remove,electrolisis can cause this and if you wash your car regularly the water goes straight into the recess and then burns off leaving a resedue.Because of where the plugs sit on the duratec and if you use the car in the rain i would whip them out once a year, duratec owners will be shocked at the outside state of the plugs although working ok water goes straight through the louvres and down the plug hole.Dont panic it wont be cross threaded just tight.



Em

As above, but also use the highest quality socket that fits the plug. Some normal spark plug wrenches are a bit low quality, and whilst are perfectly fine under normal circumstances, not as good a fit if more force has to be applied.

Do give whatever you use as penetrating oil plenty of time, rather than use too much force and cause damage.

If as I suspect, the head is aluminium alloy, be extra careful.

Once the plug starts to move, that is just the beginning. Turn the plug both ways, use more penetrating oil and take your time.

Is it worth coating the tread of the plug with grease when refitting?

Yes -- I always take out the plugs of any car as soon as I get it (have done so with the new GDI Plus 4) and lightly smear the threads with Coppaslip before re-fitting. Do not use ordinary grease. Do not over-tighten the plugs -- remember the threads are in alloy.

Sorry to hear your predicament Nick.

I don’t know the answer or ever had one stuck but if I did I would be tempted to try freezer spray through a nozzle very locally onto the steel plug body to try and shrink it (as well as the WD40 thing). I might even try and rig up a tube around the plug to keep the liquid away from the ali head. I would try it first with the head at room temperature but if that didn’t work and depending on how desperate I was I might try it with the head progressively a little warmer.

Just like to reiterate I’ve no experience of this or heard of it being done. My concern would be creating a rapid localised temperature differential in the cast ali head and the fear of cracking. Might be worth getting the professionals comments before trying?


http://www.wickes.co.uk/Wickes-Pipe-Freezing-Spray-240g/p/424922#

I would soak the plug socket with paraffin and leave overnight at least to "penetrate" you will be able to see if its seeped in.

A farmer taught me this trick 55 years ago!!

Worth a shot!

If you can't get paraffin, try a shot of diesel. That's worked for me in the past!!

And praying, of course..