MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Lucas Sports Coil Failure

Last week on the way home from work my í59 roadster just stopped running. For the first time ever I had to have a car towed home. The problem was clearly electrical and it didnít take long to trace the problem to the Lucas Sport Coil. I had installed the coil along with a complete rebuild of the ignition system last year. It appears that the coil was leaking coolant as there as a drop of oil on the lip and when shaken I could hear the coolant sloshing around.

I am sure that Moss will replace the coil, but was wondering if anyone else had had a similar experience?

John
jjb Backman

I had an original coil fail when the bracket wore a small hole in the coil and the oil leaked out. The car would run for a mile or so and then quit. After a few minutes the car would start and run a mile again quit and so went the cycle home. I thought I had a fuel blockage somewhere. I always place a piece of inner tube between the coil and the bracket now. Good luck with your repair.

Bill
Bill Haglan

John, Enclosed is a pic of how I found my coil one afernoon. The oil had been slowly leaking out of the coil since new for 4 weeks. Couldn't for the life of me figure out why it was so hard to start after it warmed up. Then one day it just stoped from the results of the picture. I gave up on Moss condensers and coils. Got the Petronix coil and points and will never go back. It's amazing how much smoother your engine runs with the electronic points.


WMR Bill

Bill and Bill,

Bill H. thanks for the tip on the bracket wear, looks like I have a similar problem.

WMR Bill, I already have the Petronix ignition and have also seen a significantly smoother idle.

John
jjb Backman

My first coil failed after 40 years. Then I went through two modern replacements in 18 months! It seems they do not like the heat from proximity to the engine. It is important not to over clamp the coil, but also it should not be loose. Some rubber at the contact points on the bracket is a good precaution.
Peter.
P. Tilbury

John,

Had a similar experience with a leaking Lucas sports coil, purchased about 6 years ago. Fortunatly discovered the leak, which was at the point where the terminal is joined to the top of the coil, during routine service prior to our departure on a 3,000 mile trip. Fitted a new standard Lucas replacement coil.

Other than a flat tyre the trip was uneventful, a failed coil would have been a major inconvenience given the lack of passing traffic and minimal to no mobile phone coverage during most of our travelling.

Good luck with a replacement / refund

Russell
R J Goebel

Much the same happened to me on a narrow road just last Sunday morning, while being followed closely by another car. The engine just went out instantly. Not a good time to remember that I hadn't got around to renewing my recovery insurance, so it took me about 4 hours and £135 to be taken the few miles home. I still haven't got the car running again, but I am suspecting, after some hours of work, that it's the coil. I had a spare with me, which I'd fitted, but that didn't work either, and now I have had a chance to put the meter over them both, they both have primary resistances of 8.6 ohm, where the book says it should be about 3.4 ohm, so I suppose that they are both duff. I'd been caught before with a similar failure, traced to those duff rotor arms which were going about as well. On that occasion too I had a new spare handy, but that also wouldn't work, and it took ages to sort that out, after which I have tried to keep some nice old-stock parts. But I haven't got a nice trustworthy old coil. Why does this new stuff have to be so fragile?

G
Gus Gander

I too was having trouble with replacement coils on both my TC ( now sold) and my MGB which would run nicely for 20 miles and then misfire when hot after replacing all the ignition parts and two new coils I still had misfiring when hot. Eventually I replaced the distributor with the 123 electronic distributor system from S C parts together with a Lucas sports coil and the transformation was instant No misfiring and a smoother acceleration right through the range together with a much lower steady idle at around 600 rpm.
My 1961 MGA Mk 2 coupe has the 25d distributor and is working well so I am inclined to leave well alone but I wonder if in the future to convert to the 123 system. Has anyone had any experience with this system on the MGA ?
Paul
P D Camp

I had a "standard" Lucas coil fail a couple weeks ago without warning. I warmed up the car, got in, drove 100' up my driveway, and the engine died just as if I'd turned off the key. Luckily it happened in my yard! The low voltage winding read dead open. No leaks, though. It was five years old.
David Breneman

I took a look at mine after reading this and found that the white insulator nose appears to have a vertical crack almost the entire length. No oil or sparks leaking-yet. It's 3 years old, and been on the car for two.

Tom Baker

This is why I'm a HUGE fan of the #40611 pertronix epoxy filled coil. The epoxy is a solid, so it won't leak out and allow the coil windings to overheat. The Bosch Blue coil is also an exceptional option. Both are around the same price as the Lucas coils or cheaper!
Jeff Schlemmer

Jeff I couldn't agree with you enough! After my incident with a brand new leaking coil, I switched both the MGA and my TR over to the Petronix coil and igniter for 80 bucks. Now it runs smoother than it ever did. Points and condensers are just not worth the aggravation.
http://www.vintageperformance.com/retrorockets/credit.htm
WMR Bill

Actually I was referring to ONLY the coil. An electronic ignition conversion is fine, but the coils filled with epoxy are inherently more stable and will never leak oil in your engine bay. Of course there are different grades, which is why I recommend the Pertronix #40611 OR the Bosch Blue coil.

As for the points or Petronix argument, I run points because I don't mind adjusting them. Standard Ignition makes great points and condensers, unlike a LOT of the aftermarket and Lucas stuff available.
Jeff Schlemmer

Well, I finally found out that it wasn't my coil that was causing the problem. It was the rotor arm. Again. (see the parallel thread on this problem).

But I'm still not too happy about the coil situation, even though the ones I have appear to work OK, as the resistance figures they show on the meter are well outside the suggested tolerance in the WM. I also keep two Sprites, and I observe that, also in 1959, the Sprite's coil was also relocated from its position on top of the dynamo to a bracket on the bodywork nearby, much as the change the MGA had for the 1600 introduction. Plainly they had had troubles with dyno-mounted coils, and needed a change. But was this due to vibration, or engine heat, or both. Has anybody got any history for this? There may be something recorded somewhere, and it must have been reasonably significant at the time to undertake the necessary new tooling and bracketry.

G
Gus Gander

I had two brand new Flame Thrower Coils 40511-Oil
filled and the 40611-Epoxy Filled 3.0 OHMS NON-BALLASTED (DLB101) go bad. Both of these did not last 1 year. Now using the Lucas Sport Coil and so far so good.

Lately I have read about quite a few post about the Flamethrower coils going bad very fast. So I am not sure about these anymore. It's not that they leak, they burn out.

Ray
Ray 1977mgb

This thread was discussed between 22/09/2008 and 05/10/2008

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.