Rover V8 spark plugs

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Sat 7 Aug 2004 22:31
Rover V8 spark plugs - owenP
I have just acquired a classic 1971 Rover P6. When I attempted to change the plugs I noticed that no plug spanner or socket (of which I have tried several of different thickness) would fit between the plug and the cylinder head in order to reach the plug. I think it is a standard 14mm plug - but was wondering if there was a special tool for removing the plugs.
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Sun 8 Aug 2004 11:23
Rover V8 spark plugs - Cliff Pope
There may well be a special Rover tool. When I had a LandRover V8 I found too that an ordinary socket wouldn't fit, but used one of those old-fashioned universally jointed box spanners. They have thinner metal than a socket.
Be very careful about stripping the threads in the Aluminium heads, especially if the plugs haven't been moved for years. Soak in WD40 and inch them backwards and forwards a bit at a time. Also as I recall they stick out at funny angles, so it is very easy to cross-thread when re-inserting because it is easy to get the angle of attack wrong.
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Sun 8 Aug 2004 22:22
Rover V8 spark plugs - THe Growler
Just done similar on my '69 Mustang. Plugs were seized solid (iron head) and I soaked them several times before trying to ease them out, even then it was dodgy, so that's a good suggestion, particularly with an ally head. Recommend a touch of copper grease as well before you put the new plugs in. Next time round removal will be easier.
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Sun 8 Aug 2004 22:30
Rover V8 spark plugs - Aprilia
I have just acquired a classic 1971 Rover P6. When I
attempted to change the plugs I noticed that no plug spanner
or socket (of which I have tried several of different thickness)
would fit between the plug and the cylinder head in order
to reach the plug. I think it is a standard 14mm
plug - but was wondering if there was a special tool
for removing the plugs.


Try a box spanner - should work.
Penetrating oil won't do much (won't get past the sealing ring) but a touch of copperslip when replacing won't do any harm. Use a 3/8" torque wrench and torque to 15-25 lbs.

I have found that a stubborn plug in an ally head sometimes comes out easier when the engine is hot.
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