Quite right Phoenix - all to easy to cross thread a plug - and a bit of rubber tubing could prevent problems if the things are too far down to use your fingers.
Obviously everything must be clean - all too easy for some dirt to fall down the hole and fall through when the plug is removed or replaced. You must make sure that the thing is virtually home before applying any significant force to it.
This is actually a sound principle when fitting anything.
spark plug questions
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stevieb
- Posts: 265
- Joined: 03 Nov 2004, 20:14
If the plugs are deep down, be sure to blow out the areas around the plugs before removal, otherwise you'll end up with a cylinder full of grit.
I did my 406 plugs tonight, and blew out the muck a second time after slackening the plugs off - and blew out another half ton (nearly) of dust that was obviously caked to the plug washers. Definitely worth doing though.
I've not bothered with rubber tubing. The plug socket has a rubber insert to hold the plug, so I just line up the plug with the socket and long extension. You can feel if the threads cross as they tighten up too soon. A safer bet is to gently turn the plug counter-clockwise and wait 'til you feel the slight drop as the ends of the threads meet (you need sensitive hands for this though - it's like finding the end of a roll of sellotape). This is usually what I resort to if I'm working at a funny angle or in a confined space.
I did my 406 plugs tonight, and blew out the muck a second time after slackening the plugs off - and blew out another half ton (nearly) of dust that was obviously caked to the plug washers. Definitely worth doing though.
I've not bothered with rubber tubing. The plug socket has a rubber insert to hold the plug, so I just line up the plug with the socket and long extension. You can feel if the threads cross as they tighten up too soon. A safer bet is to gently turn the plug counter-clockwise and wait 'til you feel the slight drop as the ends of the threads meet (you need sensitive hands for this though - it's like finding the end of a roll of sellotape). This is usually what I resort to if I'm working at a funny angle or in a confined space.
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dnsey
- Posts: 1538
- Joined: 20 Oct 2004, 01:39
- x 19
I quite agree, and suspect that there's no advantage at all in using them on a normally-tuned engine.
That's fine thenthe setting recommended is 1mm and this is also factory setting
My point was to remind the OP to check that the gap was as recommended, and thus avoid potential 'mysterious' misfiring etc.-
bxbodger
- Posts: 1455
- Joined: 23 May 2003, 03:34
- x 1
If you do go for the Bosch super 4's, don't be tempted to meddle with them- they are quite a precision thing as spark plugs go- ignore the gap specified in the manual, thats for a single electrode plug.
Super 4's don't need or want gapping, they just go straight in. I'd still recommend them for a petrol engine over a cheapie single electrode due to their durability. I've got a set in the shed that I used in two different cars, salvaging them each time the car went.....they probably have 60000 miles odd on them and still look like they are out of the box.......
Super 4's don't need or want gapping, they just go straight in. I'd still recommend them for a petrol engine over a cheapie single electrode due to their durability. I've got a set in the shed that I used in two different cars, salvaging them each time the car went.....they probably have 60000 miles odd on them and still look like they are out of the box.......
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_kid_
- Posts: 206
- Joined: 07 Oct 2005, 07:05
To update
The spark plugs were incredibly tight, with the first tool used the plug broke the plastic handle, with the second tool the metal lever bent as i was applying pressure, so i used a screwdriver as the lever (and wd40) and finally they turned, i was concerned that i would break my wrists. The hose idea at the end of the spark is a great idea, no cross threading. I have tightened them finger tight than another 1/4 - 1/2 turn, is this ok?
The spark plugs looked whitish but with some tanning, i presume this is ok. Secondly the electrode gap was large, over 1mm and visibly more then the new plugs. Why would this be the case?
The spark plugs were incredibly tight, with the first tool used the plug broke the plastic handle, with the second tool the metal lever bent as i was applying pressure, so i used a screwdriver as the lever (and wd40) and finally they turned, i was concerned that i would break my wrists. The hose idea at the end of the spark is a great idea, no cross threading. I have tightened them finger tight than another 1/4 - 1/2 turn, is this ok?
The spark plugs looked whitish but with some tanning, i presume this is ok. Secondly the electrode gap was large, over 1mm and visibly more then the new plugs. Why would this be the case?
currently no citroens 
1.4 2000 forte now gone too
xantia 1.8i 16v dimension 1996P now gone,
1.4 2000 forte now gone too
xantia 1.8i 16v dimension 1996P now gone,
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bxbodger
- Posts: 1455
- Joined: 23 May 2003, 03:34
- x 1
Maybe just a little bit more, another quarter turn.I have tightened them finger tight than another 1/4 - 1/2 turn, is this ok?
The colour sounds fine- the mixture must be spot on, and the big gap is just down to spark erosion of the electrodes, wearing them down over time. Every time the plug sparks, another few molecules of steel disappear.......
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AndersDK
- Posts: 6060
- Joined: 21 Feb 2003, 04:56
- x 1
Mind you that spark plugs with electrodes in perfect condition is no guarantee that they will function - at all 
The problem is micro cracking in the porcelain isolation, which develops as a common aging process in the plug (heat & vibration). The result is that more or less of the spark energy finds its way to engine earth before it reaches the electrodes.
At the point where most of the spark energy is shunted to earth - the plug is worn out. No matter the number or design of electrodes.
Problem is that the aging process depend on so many factors of engine behaviour - and usage.
The problem is micro cracking in the porcelain isolation, which develops as a common aging process in the plug (heat & vibration). The result is that more or less of the spark energy finds its way to engine earth before it reaches the electrodes.
At the point where most of the spark energy is shunted to earth - the plug is worn out. No matter the number or design of electrodes.
Problem is that the aging process depend on so many factors of engine behaviour - and usage.
Anders (DK) - '90 BX16Image