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MG TD TF 1500 - Coils
|I would like to replace my original coil (1954 TF) with a new coil. Moss has a replacement coil replica and also what they call a Sports Coil, Intermotor Brand. Can someone tell me what the difference is, other than price, and is one considered the better option?|
|Sports one gives probably a higher voltage; So more energy to ignite the mixture even at high RPM. But it certainly draws a higher current at primary side.|
Is it worth ?
Well I have it. Better reliability ?
I had problem with a new leaky normal one from MOSS. But maybe it was just a single defective part.
|I also run the Sport Coil. |
I have little mileage on it however.
It does take a different lead connector however.
Not screw type.
I made an adapter.
|From what I understand of the Sport Coil design, it gives higher voltage but is optimized for high RPMs and wider plug gaps. On a standard engine, the factory coil will theoretically give better all-around performance. Of course this assumes that today's sport coils are the same design as the old ones.|
|My experience right across the board is that the original equipment is a much better product. Built at a time when there was both skill in British design and pride in workmanship, the bean counters didn't run the show and things were made to last. My advice would be to stick with the original. I'll add the leaking coil to the Moss list that owners have complained about. It's approaching 100 items now! Cheers|
Peter TD 5801
|I am using the Moss Sports Coil without issue.|
.030” gap on advice from Tom Lange.
|P G Gilvarry|
|Good to know that at least the Moss Sports coil doesn't seem to leak. Cheers|
Peter TD 5801
|I am a bit confused regarding the original coils. Mine is not leaking oil/oel and I have checked it after driving a while and find it not to be hot. Would one assume that there is nothing wrong with it? |
|Moss sells the same coils as everyone else. If it goes bad then it's the manufacturer's fault, not whoever you bought it from. The "sports coil" is a Lucas product, not a Moss brand. Also, most modern coils don't use oil anymore, but instead are filled with an epoxy resin. I'm not sure what the latest Q12 repicas have inside. Maybe it's worth noting that I had two of them go bad within a few drives. Apparently this is rare (according to two different sellers) but I still went back to my old coil.
Larry, if the car runs well and the coil isn't hot then I would leave it alone. My TC has a pre-war coil that still tests (and works) perfectly fine. Generally speaking, a coil will either fail early in its life or will last almost forever.
|"Lucas" in this case having no connection with original Company, other than the name, which is used on products made in the Orient.|
|Further to Dave's post.
I've just bought an Elta 'sports' coil.
ELTA is a major automotive component importer and distributor, and a licensee of the iconic Lucas brand. Established in 1993, ELTA supplies motor factors and retailers throughout the world from its locations in the UK and Europe.
ELTA AUTOMOTIVE LTD
27 Roman Way, Coleshill, West Midlands, B46 1HQ
Private limited Company
Nature of business (SIC) - 46900 - Non-specialised wholesale trade
Previous company names -
ELTA LIGHTING LTD 09 Nov 1995 - 23 Jul 2013
MOATACRE LIMITED 14 Jun 1993 - 09 Nov 1995
Product details (from the very overpriced Demon Tweeks website) -
"The Lucas Sport coil has been used as a high performance replacement by classic and sports car enthusiasts for many years. Although branded by Lucas these coils were manufactured by Elta so these sports coils are identical in fitment and performance.
Exact replacement for Lucas sports coil DLB105
High voltage upgrade for OEM coils
Increased performance with improved fuel economy
Having a resistance of 3 Ohms makes the Elta sports coil ideal for use on vehicles with contact breaker (points) triggered ignition or with after market ignition systems.
The high output (up to 24000 volts) allows plug gaps to be increased resulting in better combustion, improved performance and better economy."
|Surprised Elta’s ad didn’t mention it would cure the common cold and warm your tea too.|
|I've been running the same Lucas Sports Coil for at least 15 years. Used with pertronix Igniter with plugs at .030". Still running strong. Bud|
|To be fair I think the advert part is from Demon Tweeks, probably to help justify the very high price they charge.
I was of the belief that coils last decades and they do, but like other parts such as spark plugs and HT leads they can continue to work way passed their best or optimum which is fine in many circumstances of use but not if you want higher performance (such as it is) out of your vehicle.
A mate who works at a place that does work on classic Jag (Jaguar) racing engines was telling me how coils can throw up quirks and a coil that gives an issue in one use is fine in another, his example was on a Lotus Elan that was fine on day of testing but the next day when the customer came to collect had a slight misfire at 6,000 revs, coil was swapped and all was fine, the coil that played up was put on another engine and was back to being fine.
For the last 12 years I've had a 'Lucas' sports coil with originally an Aldon ignitor head, and then when they became available for my model of (modern) midget, a 123 fully electronic dissy. On the rolling road 0.025" (middle of factory 0.024"-0.026") spark plug gap was tried, back to my setting of 0.8mm (0.031") and then 0.028" was tried. The 0.028" was found to be the best on my car set up, so wider but not the oft stated 0.030" and no where near 0.035" that some stated.
|ETA: just thought, I wasn't suggesting 0.030" was a wrong gapping for spark plugs, only giving an example of proven advantage of a wider gap in the right circumstances.|
|I have attached a PDF about original TF coils based on research that I did a few years ago. Can't guarantee the total correctness, but best info that I could find.|
|Lonnie-- Thank you for the pdf. Very interesting. It seems to be a bit of a sticky situation in that my coil may be just fine or it may not be. I wonder if coils can go bad intermittently? It would seem to be possible though when I had my problem I had not driven long enough for it to get hot. I have driven much further since then and felt the coil but found nothing unusual. I am now going through all of the wiring to make sure they are OK though I doubt if I will find anything wrong since I put in all new wiring when I rebuilt the car. My coil is of the Lucas Q12 type though a previous owner painted the coil a gold color (for some reason). I have another coil, same type, but I don't know if it works. Since I am disconnecting the wires to check them I think I will connect this coil just to see if it works. If it does it can be used as an emergency backup. Of course if the engine quits as it did before and I am in the middle of the freeway at rush hour then it really wouldn't matter as it would have turned out to be a very lousy day for me (and for my soon-to-be widow).
|I'm curious about the bracket attached to the Q 12 coil pictured on the right. Can anyone confirm if this bracket was originally fitted to the original Q 12 on the TD? The bolt that remains is marked 2 BEES 2, so it is definitely of the period. I would also like to know about the arrangement and type of washers on each of the posts. I know that the double brass 2 BA nuts shown on the repainted coil isn't as it was originally. Cheers|
Peter TD 5801
|Had the answer offline. The bracket is from another marque. I have two restored Q12 coils from 1951 now. Both test at 3.5 ohms on the primary and about 30,000/35,000 ohms on the secondary. Simple test with an ohmmeter. Just be sure that there is good contact otherwise you might be ditching a good coil. I'm glad I persevered with the rusted one as initially the was no reading on the secondary winding. Cheers|
Peter TD 5801
|My 55 TF matching number car 8353 built Dec. 17,1954 still has the original LA12 coil and it works just fine with the original points distributor, I believe in the old saying, if it ain't broke don't fix it! I couldn't ask for my engine to run any better. I do keep a spare coil, just in case! PJ|
|This is all very interesting as I suspect I am currently having coil issues. My system is still "+" ground so is it correct if I use a new 3.0ohm coil, the ignition side of the coil should be negative and the lead to the dizzy will be on the positive terminal?|
Thanks so much,
Bill Brown TD24570
For pos. grd. positive (CB) terminal goes to the dizzy. You are correct.
This thread was discussed between 08/09/2020 and 02/10/2020
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