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MG MGF Technical - 'Mind the gap' : new plugs

Hi,I have just bought some new NGK Platinum plugs and magnecor leads and would like advice re plug gaps.
The plugs are preset at 1.1mm, but there are plenty of references to the gap being set to 1.0 mm. NGK seem to caution aganst resetting the gap due to the risk of damage to the electrode. I just leave them as set?
Also, antiseize on the threads or not?


MGF VVC 1996, around 96 000 miles now.
Charles Dundas

When I last fitted plugs in our F and son's F(some years ago now…) I definitely adjusted the gap to the correct setting without problem. I remember trying to find the feeler gauge (having not used it for 20+ years with company cars!) I am also 99.9% certain that we used the NGK plugs as these are the ones recommended by MGR. I also fitted the Magnecor leads at the same. You should notice the difference!

Didn’t bother with anitseize or using a torque wrench – real men can feel when they are tight enough!

The car is up for her 10 year service next month and think the plugs will be changed again with the cam belts so will probably leave it to the garage this time!

Leave the gaps as they are. The gap references are for OEM plug not the NGK Platinum jobs which because of their contruction the gaps can be a little bigger. I use a smiggin of copper grease on the threads of mine.
Blue Pocket Rocket

I adjusted mine - they're not set for a particular application - but then again, as can be seen by other responses on this thread, the last 1/10th of a millimetre gap adjustment appears not to be that critical! ;o)
Rob Bell I or don't I?????
Charles Dundas

The manual says fit platinum plugs with a gap of 0.9mm +/- 0.1mm. It does not mention that this rule does not apply to NGK products.....

Well the manual wouldn't mention NGK products would it Patrick. The NGK platinum plugs come pre-gapped so no need to adjust them.
Blue Pocket Rocket

Gosh, do you mean you can buy plugs without gaps?

The manual from the engine manufacturer specifies a gap. Why would you not follow the manufacturer's recommendation?

It's always best to check the gaps - they can become closed up (or even opened up) in transit - certainly the plugs I've come across have had variable gaps, despite being 'pre-gapped'...
Rob Bell

> The manual from the engine manufacturer specifies a gap. Why would you not follow the manufacturer's recommendation?

Surely it's better to follow the rec of the plug manufacturer than the car manufacturer?

What, you would propose to follow the thoughts of a manufacturer of a very simple component (even primitive?) over those who designed and produced the whole engine?

I suspect the plugs are churned out of some sweat shop in China between lead painted toys and antifreeze tainted toothbase.

I know I have zero problem working out which set of instructions to follow.

This thread was discussed between 08/08/2007 and 14/08/2007

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