Poor Ignition Coil Reliability (thoughts?)

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svenedin
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Re: Poor Ignition Coil Reliability (thoughts?)

Post by svenedin »

Bill_qaz wrote: Sat Aug 22, 2026 2:54 pm Stephen, as the resistance plug caps are purely to suppress interference and nothing to do with engine performance.
Could you not fit non suppressed plug caps,readily available, as there are no electronics to be interfered with on your minor
Bill, yes I could but I think suppression is a legal requirement? I remember as a child how annoying it was to hear the interference on the radio at home so I don't want to be a mobile nuisance to others. For now a set of standard suppressed carbon string Lucas leads are on the car and it ran very eagerly earlier. They are pretty reasonably priced and actually seem good quality which is a bit of a surprise for modern "Lucas". I will carry a spare set of these leads in the car pre-installed on a distributor cap then that is a rapid fix at the roadside. Of course I am now in the habit of checking spare parts by running them on the car on a test drive (if this is practical) rather than assuming that what I have in the boot as a spare actually works!

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

Post by Bill_qaz »

svenedin wrote: Tue Aug 11, 2026 3:43 pm
Bill_qaz wrote: Tue Aug 11, 2026 3:18 pm Stephen, managed to grab a pic today. Its a Lucas coil and is bolted to the inner wing near the rebound stop bracket. Bit of a clean up and terminal fix on schedule now I've seen it for the first time since buying the car. :lol:
20260811_122731.jpg
Thank you. What you've got there is a good old coil of the type Myoldjalopy refers to. That's an old Lucas logo on the coil bracket. Yes clean up the terminals, give it a wipe and put it back! Whatever you do, don't join the Russian Roulette game of modern coils!!!

Stephen
Rerouted the tight wire and cleaned the top :o its actually white,it was just dirt. The Lucas is plain to see and noticed the connection points are raised on the top. Is this one of the older versions you referred to?
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Re: Poor Ignition Coil Reliability (thoughts?)

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Bill_qaz wrote: Sat Aug 22, 2026 8:28 pm
svenedin wrote: Tue Aug 11, 2026 3:43 pm
Bill_qaz wrote: Tue Aug 11, 2026 3:18 pm Stephen, managed to grab a pic today. Its a Lucas coil and is bolted to the inner wing near the rebound stop bracket. Bit of a clean up and terminal fix on schedule now I've seen it for the first time since buying the car. :lol:
20260811_122731.jpg
Thank you. What you've got there is a good old coil of the type Myoldjalopy refers to. That's an old Lucas logo on the coil bracket. Yes clean up the terminals, give it a wipe and put it back! Whatever you do, don't join the Russian Roulette game of modern coils!!!

Stephen
Rerouted the tight wire and cleaned the top :o its actually white,it was just dirt. The Lucas is plain to see and noticed the connection points are raised on the top. Is this one of the older versions you referred to?
20260822_201351.jpg
Yes it is definitely a "vintage" Lucas coil with the style of the raised platforms that the connectors sit on. The modern ones have turrets. We can tell it's not especially ancient because it's marked + and - and not SW and CB. Despite the "Super" sticker on the bracket it may well be an LA12. At a guess I'd say it's 1980's or even 90's because the earlier Lucas coils had black plastic not white. Somewhere I did have a 1969 Lucas coil, possibly my car's original that was marked + - by then. As with all Lucas products at that time, it is date stamped on the bottom. Yours is probably date stamped as well.

Stephen
Last edited by svenedin on Sat Aug 22, 2026 9:30 pm, edited 1 time in total.
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

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Thanks to everybody who helped with the coil woes. A lovely drive out this evening without any issues. Titsey Brewery, Westerham, Kent on the top of The Downs. Spectacular view and a good supper. Great beer, shame I could only have 1 pint of bitter shandy. A crime to mix good beer with lemonade but hey ho. Morris is hiding keeping watch.

Stephen

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1969 1098cc Convertible “Xavier” which I have owned since 1989.

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Re: Poor Ignition Coil Reliability (thoughts?)

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What is it with me and ignition coils?!!! Driving to the Cotswolds from South London. At Reading services thought I should do a quick check under the bonnet. The coil had fallen out of its bracket!!! I’m sure it was tight. I blame that awful concrete slab section of the M25. It shakes the Morris to bits. Easy fix, on way again.

Stephen

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1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

Post by 59Elva »

My solution to that problem years ago was several turns of electrical tape around the coil on either side of the bracket but your engine bay is too pretty for that. Maybe a single turn of friction tape or thin rubber material hidden under the clamp?
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Re: Poor Ignition Coil Reliability (thoughts?)

Post by myoldjalopy »

svenedin wrote: Thu Aug 27, 2026 12:06 pm What is it with me and ignition coils?!!! Driving to the Cotswolds from South London. At Reading services thought I should do a quick check under the bonnet. The coil had fallen out of its bracket!!! I’m sure it was tight. I blame that awful concrete slab section of the M25. It shakes the Morris to bits. Easy fix, on way again.

Stephen

Same thing happened to me, many years ago in a traveller on a motorway, but one of the coil terminals shorted out somehow and the car just stopped! Fortunately, I saw what had happened as soon as I opened the bonnet and an easy fix - we like them! 8)
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Re: Poor Ignition Coil Reliability (thoughts?)

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59Elva wrote: Thu Aug 27, 2026 12:40 pm My solution to that problem years ago was several turns of electrical tape around the coil on either side of the bracket but your engine bay is too pretty for that. Maybe a single turn of friction tape or thin rubber material hidden under the clamp?
Good idea. A turn of tape around the coil that is hidden under the bracket. Thank you!

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

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myoldjalopy wrote: Thu Aug 27, 2026 1:13 pm
svenedin wrote: Thu Aug 27, 2026 12:06 pm What is it with me and ignition coils?!!! Driving to the Cotswolds from South London. At Reading services thought I should do a quick check under the bonnet. The coil had fallen out of its bracket!!! I’m sure it was tight. I blame that awful concrete slab section of the M25. It shakes the Morris to bits. Easy fix, on way again.

Stephen

Same thing happened to me, many years ago in a traveller on a motorway, but one of the coil terminals shorted out somehow and the car just stopped! Fortunately, I saw what had happened as soon as I opened the bonnet and an easy fix - we like them! 8)
Haha. I’m very lucky the coil didn’t end up smashed on the road and instant engine cut out! Naturally enough I do have TWO spare coil in the boot :lol:

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

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Im wondering if cloth friction tape is still around. My dad spent fifty years with the telephone company. There was always a roll in his pocket and when mom did the wash they would often accumulate near the washing machine so I always had access to the stuff which I found a myriad of uses for. Duct tape might be too slippery. A few wide rubber bands or a section of bicycle inner tube might be the ticket.
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Re: Poor Ignition Coil Reliability (thoughts?)

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svenedin wrote: Thu Aug 27, 2026 12:06 pm What is it with me and ignition coils?!!! Driving to the Cotswolds from South London. At Reading services thought I should do a quick check under the bonnet. The coil had fallen out of its bracket!!! I’m sure it was tight. I blame that awful concrete slab section of the M25. It shakes the Morris to bits. Easy fix, on way again.

Stephen
Actually, what I found interesting in your photo, apart from the Coil having fallen out (and that incredibly shiny clamp), was the Mounting Bracket with the 'Plate - Steady'.
According to the AKD 3541, the mounting bracket you have with the gap filled in (for want of a better description), replaced the earlier open style probably late 1959, from engine 9M/U/H/357434 and /L/357020. At which point they stopped using the 'Plate-Steady', never using it on the 10MA.... :-?

Most curious. :wink:
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10MA.JPG
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.
.
As to your issue of the Coil slipping out of the bracket, a wrapping of electrical tape, under the clamp, would also eliminate any risk of fretting between clamp and coil casing, thus preventing an oil leakage.
:tu1:
Basil the 1955 series II

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Re: Poor Ignition Coil Reliability (thoughts?)

Post by Bill_qaz »

svenedin wrote: Thu Aug 27, 2026 2:00 pm
59Elva wrote: Thu Aug 27, 2026 12:40 pm My solution to that problem years ago was several turns of electrical tape around the coil on either side of the bracket but your engine bay is too pretty for that. Maybe a single turn of friction tape or thin rubber material hidden under the clamp?
Good idea. A turn of tape around the coil that is hidden under the bracket. Thank you!

Stephen

Even your coil is trying to move itself to inner wing Stephen. :lol: :D :tu1:
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Re: Poor Ignition Coil Reliability (thoughts?)

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The shiny coil bracket is only that shiny because it has a foil sticker on it. The coil canister is chrome though. Pertronix coils are either chrome or painted black. The coil steady is a reproduction in stainless steel to replace the rusty original that is in a box somewhere. I didn’t know it was discontinued during production. It was on my car when I got it in 1989.

Stephen
Last edited by svenedin on Thu Aug 27, 2026 6:20 pm, edited 1 time in total.
1969 1098cc Convertible “Xavier” which I have owned since 1989.

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Re: Poor Ignition Coil Reliability (thoughts?)

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Bill_qaz wrote: Thu Aug 27, 2026 5:53 pm
svenedin wrote: Thu Aug 27, 2026 2:00 pm
59Elva wrote: Thu Aug 27, 2026 12:40 pm My solution to that problem years ago was several turns of electrical tape around the coil on either side of the bracket but your engine bay is too pretty for that. Maybe a single turn of friction tape or thin rubber material hidden under the clamp?
Good idea. A turn of tape around the coil that is hidden under the bracket. Thank you!

Stephen

Even your coil is trying to move itself to inner wing Stephen. :lol: :D :tu1:
Funny you say that. I actually thought that when I saw it! I also noticed that with the coil lying on the floor of the engine bay it wasn’t hot at all.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

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59Elva wrote: Thu Aug 27, 2026 4:37 pm Im wondering if cloth friction tape is still around. My dad spent fifty years with the telephone company. There was always a roll in his pocket and when mom did the wash they would often accumulate near the washing machine so I always had access to the stuff which I found a myriad of uses for. Duct tape might be too slippery. A few wide rubber bands or a section of bicycle inner tube might be the ticket.
Something like old fashioned Elastoplast would work well I think. It comes in rolls. It could be stuck around the inside of the clamping hoop rather than on the coil itself.

Stephen

Stephen
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Stephen
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Re: Poor Ignition Coil Reliability (thoughts?)

Post by Bill_qaz »

Just a thought Stephen, was the coil clamping bolt full tightened before the holding down bolts, they would restrict closing if tightened first. Are they slotted?

Where in the cotswold did you visit?
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Re: Poor Ignition Coil Reliability (thoughts?)

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Bill_qaz wrote: Thu Aug 27, 2026 8:39 pm Just a thought Stephen, was the coil clamping bolt full tightened before the holding down bolts, they would restrict closing if tightened first. Are they slotted?

Where in the cotswold did you visit?
Yes tightened before fitting as no way to tighten in situ anyway (fixing studs obstruct the clamp screw) . Bracket slotted. Just wasn’t tight enough but I thought it was tight. I didn’t want to risk crushing the coil canister by being heavy handed.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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