Technical Head help
- Thread starter leroya500
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Technical Head help
Heads are never steel. The fire engine like yours is aluminium alloy casting. The other material is cast iron but not in your case.
Has the plug been removed and only got so far in (cross threaded) or won't it come out?
Has the plug been removed and only got so far in (cross threaded) or won't it come out?
Put it all together and get the engine warm, often the alloy will grip less once warm. Also spray some plus gas round the base of the plug, use a good breaker bar and decent plug socket. Give the threads a decent covering of copper grease on reassembly, only tighten enough to compress the sealing washer. Fingers crossed the thread is ok, otherwise you'll need a helicoil insert.
Exactly that - give the base of the plugs a really good penetrating fluid dowse and leave it for a good while. then start engine to get it nicely hot and follow above instructions. A REALLY good quality plug socket is vital and then just be accurate and assertive with the big breaker bar on the socket. Should come out fine.....
Let us know how you get on!
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DO NOT swing on the plug with a long breaker bar for leverage!
You will no doubt snap the plug off in the head, just leaving the threaded part of the plug stuck in the hole and the plug's core will drop into the cylinder.
There's not much to the body of a plug and if they're starting to rust up, they are prone to breaking.
Soak & Heat are your friends, not brute force!
You will no doubt snap the plug off in the head, just leaving the threaded part of the plug stuck in the hole and the plug's core will drop into the cylinder.
There's not much to the body of a plug and if they're starting to rust up, they are prone to breaking.
Soak & Heat are your friends, not brute force!
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Hi. I'm not advocating brute force, using a short bar will often make you apply the pressure on it at a less than good angle, using common sense here is the key, a hot engine and plus gas. I've encountered many stuck plugs but never broke one yet!!
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Youtube's full of numpties that have broken them off!
I've struggled myself with an old shed of a Fiesta that my bro in law was running around it.
He snapped off three before he rang me, thanks I thought!
I got the fourth out by using some mild heat and some spray to expand and contract it.
And got lucky drawing the old threads out of the other three with a reverse threaded extractor after heating them up.
Luckily, nothing dropped into the cylinders, otherwise I'd have walked away!
I've struggled myself with an old shed of a Fiesta that my bro in law was running around it.
He snapped off three before he rang me, thanks I thought!
I got the fourth out by using some mild heat and some spray to expand and contract it.
And got lucky drawing the old threads out of the other three with a reverse threaded extractor after heating them up.
Luckily, nothing dropped into the cylinders, otherwise I'd have walked away!
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The idea once the engine is warm and the base of the plug well soaked in plus gas is to slowly rock the bar back and forth, this usually will ease off the most stubborn plug. Being over zealous can make them split but it's getting the feel of what's happening that will either be a success or failure.
3 in 1 won't penetrate like Plus Gas with is a proper penetrating oil.
Got home with a warm engine, tried first with the spring plug spanner but wouldn't move.
Hunted around for a proper plug socket and amazingly found one,however it was was for a lawnmower and had no way to attach it to a rachet, i persivered and found a socket to go tightly over it then connected to an extendy bar and a t leaver.
Put it over the plug and went for it, it slipped, so i tried again, 'slip' 'crack' , oh no, has it broke the plug? Has it rounded off?, Tried with a different socket, no grip, is it rounded off, better put it back together, but wait, the end moves, does this mean it's sheared?
I get some pliers to see if the worst has happened,but the plug is still intact! Wait, it finger tight! It's unscrewing! Yes! It's out ( threads covered in oil)
I am the man, it's done and changed!
Hunted around for a proper plug socket and amazingly found one,however it was was for a lawnmower and had no way to attach it to a rachet, i persivered and found a socket to go tightly over it then connected to an extendy bar and a t leaver.
Put it over the plug and went for it, it slipped, so i tried again, 'slip' 'crack' , oh no, has it broke the plug? Has it rounded off?, Tried with a different socket, no grip, is it rounded off, better put it back together, but wait, the end moves, does this mean it's sheared?
I get some pliers to see if the worst has happened,but the plug is still intact! Wait, it finger tight! It's unscrewing! Yes! It's out ( threads covered in oil)
I am the man, it's done and changed!
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Well done that man
Good result for you. Don't forget to use copper grease on the threads of the new plugs and they only really need to be nipped up, no swinging on the Tommy bar
Depends how much each nip is.
Plugs with a washer need the washer squashed, usually about a 1/2 a turn from lightly seated. NGK say refer to individual plug packaging. I have a box from a DCPR7E-N-10, which shows a 1/2 turn to tighten it.
The sealing washer is designed to crush. It is also part of the heat path, to maintain the correct tip temperature. If you undertighten it, the washer does not crush enough, the plug runs hot, holed piston can result.
