Spark Plug boot pops off
Thread Starter
Instructor
Joined: Jun 2001
Posts: 209
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From: Ashburn, VA
Spark Plug boot pops off
My #5 spark plug boot keeps popping off after a short amount of driving.
Is this a normal occurance after changing plug wires? I'm hoping it's just moisture inside that's heating up and causing it to come off - but could there be leakage from the combustion chamber through the threads? Anyone ever experience this?
Thanks,
-Ben Allison
Is this a normal occurance after changing plug wires? I'm hoping it's just moisture inside that's heating up and causing it to come off - but could there be leakage from the combustion chamber through the threads? Anyone ever experience this?
Thanks,
-Ben Allison
Drifting
Joined: May 2001
Posts: 2,747
Likes: 3
From: Owasso, OK
Could be either the adhesive that bonds the insulator to the metal part of the sparkplug is leaking or the sparkplug is incompletely installed or crossthreaded. One other possibility is a cracked head. Hope it's a bad plug.
Dennis
Dennis
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Joined: Oct 2003
Posts: 7,210
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From: Nova Scotia
Too warm to retain moisture, so either the plug is not sufficiently tightened, or in rare cases, I've seen a plug insulater not seal to the metal body. Pull #5 wire, start up on 7 cyls, and place a length of hose (stethoscope) in the well to listen for escaping exhaust. - or simply, try a spare plug.
Nordschleife Master
Joined: Jul 2003
Posts: 7,743
Likes: 78
From: Minneapolis
Maybe you're not getting the wire fully clipped onto the plug electrode. Or that is loose.
Oil on the threads could be coming from the outside. I'd look at the face of the plug as to whther there's excess oil in the chanmber. Yellow or golden is fine. Black and caked-up is bad.
Oil on the threads could be coming from the outside. I'd look at the face of the plug as to whther there's excess oil in the chanmber. Yellow or golden is fine. Black and caked-up is bad.
Addict
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Joined: Jan 2002
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From: Sweden
Ben,
Oil on the threads is AFAIKT unlikely to come from the cylinder - oil in the sparkplug hole on the other hand (leaking through a bad cam-cover seal) would run down the thread when the plug is removed. Is there oil anywhere else on the plug?
I had this on all 8 plugs a year ago - I had the seal, and an army of O-rings, replaced which solved the problem. (PO had just tightened the bolts when it first started leaking and squashed all the O rings).
It's an easy fix, took a bit of time, but at least they're relatively cheap parts
.
Oil on the threads is AFAIKT unlikely to come from the cylinder - oil in the sparkplug hole on the other hand (leaking through a bad cam-cover seal) would run down the thread when the plug is removed. Is there oil anywhere else on the plug?
I had this on all 8 plugs a year ago - I had the seal, and an army of O-rings, replaced which solved the problem. (PO had just tightened the bolts when it first started leaking and squashed all the O rings).
It's an easy fix, took a bit of time, but at least they're relatively cheap parts
.
