HT leads popping off

[MartinN]

My Ht leads on my Griff keep popping off the spark plugs on a regular basis. Is this a common problem? Will it be solved be just buying a new set of leads?

[Bruce Fielding]

Only happened once to me (so far...) but it sounds like one sick puppy when it happens, doesn't it?

[philtvr]

Is the rubber to far down, if it is it will pop the lead off. Pull the rubber back up the lead a bit to stop the problem and allow the lead to clip to the spark plug properly

[Marshy]

Is it the HT lead or the spark plug extension?

One or two of my extensions are, umm, a bit past it, so I bought a couple of new ones. The new ones are *so* much more secure that I'm thinking of replacing the whole lot for peace of mind.

Mind you, they're 8 quid a shot from Vauxhall. Don't be tempted to do without the extensions either... putting the HT lead direct on the plug brings it that bit too close to the exhaust manifold, and it'll be furqued in no time. 300 miles with one like that completely toasted the rubber on one side of the lead.

[MartinN]

It's just the lead that pops off so I'll see if pulling the rubber back helps, thanks.(and yes it sounds like a dump truck when not firing on all cylinders).

[anjago]

I've just ordered some magnecor leads and some steel capped adaptors, although the leads are expensive, the adaptors are 2 quid each.

[Griffer]

The Magnecors are a worthwhile upgrade, you will find that the plug extensions they supply for 2 quid are the ones without the inbuilt suppresion resistor which often fails on the standard Griff ones,thats why they are cheaper, as the Magnecors are themselves suppressed by their constuctional design not a problem.

[glena]

My red Magnecor plug leads (mainly number 1 plug) occasionally pop off the spark plug extension at running temperature.
Has anyone any experience of this?

Perhaps it is because the rubber Magnecor cap is such a tight fit on the extension that the expanding trapped hot air inside causes this!
Any other thoughts ?

[beano500]

Hmm!? I think Edt reported something similar....


....have you tried a search?

There was certainly a theory like yours placed in the dark dingy corners of my brain not so long back....

[glena]

beano500 said:

Hmm!? I think Edt reported something similar.... ....have you tried a search? There was certainly a theory like yours placed in the dark dingy corners of my brain not so long back....

Tried a search, no joy!

[glena]

beano500 said:

Hmm!? I think Edt reported something similar.... ....have you tried a search? There was certainly a theory like yours placed in the dark dingy corners of my brain not so long back....

Tried a search, no joy!

[Edt]

beano500 said:

Hmm!? I think Edt reported something similar.... ....have you tried a search? There was certainly a theory like yours placed in the dark dingy corners of my brain not so long back....

that's right I did...

BlueSatin (Guy) showed me a simple trick with a screwdriver.. it was to increase the circumference of each lead's (ooh dear dont know correct name) shroud. They used to pop off the dizzy now & again. They all now stay put; now each time I have the bonnet open I give them a check & push them securely home to make sure.

hope this helps

Ed

[glena]

Edt said:

beano500 said: Hmm!? I think Edt reported something similar.... ....have you tried a search? There was certainly a theory like yours placed in the dark dingy corners of my brain not so long back.... that's right I did... BlueSatin (Guy) showed me a simple trick with a screwdriver.. it was to increase the circumference of each lead's (ooh dear dont know correct name) shroud. They used to pop off the dizzy now & again. They all now stay put; now each time I have the bonnet open I give them a check & push them securely home to make sure. hope this helps Ed

Thanks Ed but what exactly did you do?

[Boosted Ls1]

Shove a posi-drive screwdriver up inside the boot and expand the metal cap that clips over the spark plug. That's what you do Don't make it to big though otherwise you'll have to crush it a tiny bit to close it up. Don't do this in a vice chaps

[Edt]

BOOT - that's the word I was groping for.. phew.. ta Boosted !

Ed

[jam1et]

This usually caused when the the rubber boot is a tight fit. It just basically traps air inside as you push it on. This pressurised air can make the boot work loose and pop off. Just put them on carefuly and this shouldnt happen. Alternatively do what i did. Get one of those tubes that comes with a can of WD40 or similar. Cut off about an inch length of it. Put this inside the boot as you slide it onto the dizzy cap (making sure a bit sticks out the bottom). This relieves the pressure as you shove the boot on. Then just pull the tube out with a pair of needle nose pliers.

[glena]

jam1et said:

This usually caused when the the rubber boot is a tight fit. It just basically traps air inside as you push it on. This pressurised air can make the boot work loose and pop off. Just put them on carefuly and this shouldnt happen. Alternatively do what i did. Get one of those tubes that comes with a can of WD40 or similar. Cut off about an inch length of it. Put this inside the boot as you slide it onto the dizzy cap (making sure a bit sticks out the bottom). This relieves the pressure as you shove the boot on. Then just pull the tube out with a pair of needle nose pliers.

Thanks Jamie, I was toying with the idea of putting a hot pin through the rubber cap so that it could act as a breather hole!


>> Edited by glena on Monday 12th July 18:54