MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

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 TD TF 1500 - Coil Resistance - HT and LT

In my quest for a coil with a screw-in high tension terminal, a forum member came to my rescue and GAVE one to me. Not to look a gift horse in the mouth, but I did some measurements. (He told me to toss it if it doesn't perform well.)

> Will the "free" coil deliver the required voltage output? I'll install it, but want to know if I can do better.

I measured the restance between the low tention terminals on three coils. I also measured the resitance between a low tension terminal and the high tension terminal. Here are the results:

LUCAS SPORT:
3.2 ohms = LT to LT
8,600 ohms = LT to HT

NO NAME COIL THAT I HAVE:
(possibly defective when hot)
3.3 ohms = LT to LT
7,700 ohms = LT to HT

"FREE" COIL:
3.9 ohms = LT to LT
7,300 ohms = LT to HT

FYI - the Lucas coil performs fine, but it has a push-in HT terminal.

Thanks for your help,

Lonnie
TF7211
LM Cook

For what it's worth I poured over the same sorts of data that I could obtain from various sites on assessing the health of coils using measurements etc. I ran bad coils, good coils and some questionable. Outside of the obvious shorts or open circuits I never could get a reliable means to measure the quality of coils versus just putting them on the car and seeing if they worked.

If you crack this nut the world will be forever grateful.
Christopher Couper

Try emailing Jeff at Advanced Distributors. If anyone knows, he does. jeff at advanceddistributors dot com
J Cosin

Lonnie, I don't recall ever seeing your basic reason for wanting the screw-in terminal coil. Could you refresh me on that? Bud
Bud Krueger

Bud -

There is no performance or mechanical reason. I just want one for pseudo authenticity.

Lonnie
TF7211
LM Cook

My HT lead kept falling out of the push in coil.
I kept wishing for a screw in one.

I think the fix I posted took care of that.

Jim B.
JA Benjamin

Did TFs have a screw-in HT coil terminal? Bud
Bud Krueger

Bud -

Yes, TFs had coils with screw-in HT terminal. Early models had solid filled black coils like TD coils. Taller and smaller diam than modern coils.

Later models had oil filled unpainted natural metal coils that were larger diam and shorter like modern coils. They also had screw-in HT terminal.

Good photos of the later coil on TF9052 on Chris' site. I'm away from my computer so I can't post a photo of the coil on TF9052.

Lonnie
TF7211
LM Cook

Lucas LA-12 coil in TF9052

Lonnie
TF7211

LM Cook

Lonnie
Here is the husky big boy that came with my TF. Still works fine.

Tom
'54 TF

T Norby

This thread was discussed between 01/10/2015 and 02/10/2015

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now