Knowledge Base

Some people might experience Magnecor leads lifting off after time. This is a suggested solution.

Pop-off in Magnecor leads
by Leon

I've seen numerous posts regarding problems with Magnecors popping off, but can't remember seeing any posts with a solution to this notorious problem (where a lead becomes detached from the sparkplug and the engine misfires). Therefore I thought it'd be worth typing the following to stop folks being deterred by thoughts of Magnecors causing them problems.

I bought a set of KV85's a few months ago, and within the first 100 yards of driving one of the leads had been blown clear of the sparkplug well, and the engine was misfiring.

I'd checked and double checked the leads to make sure they were fitted properly, but tried re-fitting them and continued the drive. The popping-off business continued despite my best efforts, so I emailed Magnecor basically saying that if they couldn't come up with a solution I'd like a refund.

I got a reply from Phil De Wit, and he telephoned me not long after. He explained that there are 2 breather holes on each lead- one at the bottom of the rubber boot where it attaches to the sparkplug, and one in the rubber boot which seals to the valve cover of the engine.

One or more of these breather holes is sometimes blocked during manufacture, and if this happens the air trapped in the sparkplug wells has nowhere to go when it heats up and expands (during engine operation).

I checked each lead and sure enough all of the bottom breather holes were blocked. After removing the silicon sealant from these breather holes and re-fitting, I had no more "pop-offs" and still haven't up to now.

They really are great leads as well - I definitely noticed an improvement in engine response, especially low down. The engine also idles much more smoothly, and they look good.

No I'm not on Phil's payroll, but I was almost deterred for life from buying Magnecors which would have been a shame as they're a great product. So anybody who's put off, don't be - they're unlikely to pop off and if they do it's simple to fix.

Also check the Magnecor FAQ at http://www.magnecor.co.uk/

: Sat Apr 02, 2005 5:04 pm

Hello dude
I can work it out!I remove all the leads looking for these small holes!I unblocked them with a sharp tool and nothing happent! Did I found the holes? I am not sure! Are these tiny little holes on the top black plastic "fuse"? Please help!!