Ignition coil 16c6?

Already founded much informations in forum.

Coil have a ballast next.

Have you notice about this 16C6 coil + ballast today parts numbers / lucas code ?

Truly my coil is a 6Volts ?


Not sure about the numbers but yes the coil will be a 6v if the car has a ballast resistor. The ballast resistor drops out of circuit while the car is being started, giving the coil the full 12v for a boost to the park plugs.

I don’t think that s so!

The use of a 6v coil is counter intuitive to the need for a resistor .

OTH. , using a 12 v coil might be. Crank and fire on 12.

Run on 5 for the protection of points and condenser !

Archaic, if points and condenser have been superceded by an electronic device. Ala SIII or pertronix.


The nomenclature is confusing, Carl. I don’t know why they even called these coils 6 volt–may have come around when batteries were changing from 6 to 12. Maybe they actually retained 6V system coils for 12V cars.

Anyway, the more correct terminology is “self-ballasting” and “external ballast,” both pertaining to points ignition. It has to do with the coil’s internal resistance. Too low and the coil will get hot, especially if ignition is on, engine not started, and points happen to be closed. So it has to be about 3 ohms–which makes 40 watts of heat. OTOH you can use a 1.5 ohm coil, but add an external ballast, so the heat is distributed between the ballast resistor and the coil. The latter is often wired so that the battery voltage bypasses the resistor whilst starting–overcoming the loss of voltage when the battery is loaded by the starter motor.

The lower resistance coils give better spark…for complicated reasons involving inductance. Electronic ignition systems sometimes use ~0.8 ohm coils. But the electronics prevents the coil from getting continuous voltage (longer dwell than necessary), so they can get away with it. With MSD and other capacitive discharge ignitions, the coil gets no continuous current and barely heats up at all. IMHO.


thank you!

Founded many users changed this coil with a 12V but some tell about fire problems …

To evitate problems looking for same coil , i’m sure car running fine with this one…however can’t found a substitute.

Some fonts tell use c35812 / 45227 or dlb110…i already this codes founded but really not sure…

PS yes i confirm i have a ballistor here !


It’s somewhat academic, Fred - nominally the coil just steps up the car voltage to HT ignition voltage. Principally either coil ‘voltage’ will do from either car voltage - it’s sort of roundabout and carousel factors, elucidated by Robert…

As he says; with points ignition the external resistor is essential for either coil - to prevent coil burnout with engine stationary ad ign ‘on’. However, with engine cranking the resistor will interfere with spark energy - so it is bypassed while cranking…

With EI systems a resistor is sometimes used to protect the electronics by reducing coil current - sometimes built into the coil and sometimes external. Cranking bypass is not used - and EI systems positively break coil neg/ground unless the engine is running, preventing stationary overheating dangers…

To make sense of coil selection; you will need intimate details on their inside composition - which is not readily available. Otherwise; most general coils will run any engine/ignition system…

As an aside, with EI; any coil/car voltage combination will give double or triple HT voltage compared to points ignition. Which is why 6V coils are preferred for points ignition - and necessary for 6V car systems…

xj6 85 Sov Europe (UK/NZ)

Thank you Frank.

i hope start car Tomorrow…

Actually, the coil “steps up,” via a typical turns ratio of 1:100, the “back EMF” or back voltage generated by the primary when it goes open circuit and its magnetic field collapses. That back voltage is around 600V. The ~600V zener in the AB14 ignition amplifier is there to protect the amp from excessive back voltage. IMHO.

1 Like

Indeed, Robert - and if the Zener fails (seldom!) wholly or in part, there is a ground path from coil neg to ground. Which interferes with ignition in odd ways…:slight_smile:

xj6 85 Sov Europe (UK/NZ)

Obviously car doesn’t start…

Smoke come from start relay…

Desolate i do start another question for you…

Does the engine actually crank, Fred - and are the relay connections correct…?

It may just be a faulty relay; dirty internals may cause the relay to overheat…

xj6 85 Sov Europe (UK/NZ)

Frank ,

First idea was leave all ignition components immaculate during engine/suspension/gear works.
in fact ignition was ok before engine works.

During works founded oxidation process in stabilzer/LH side, particularly next to elephant nose (exit rain water) so i decided to paint this part and obviuosly other side too (coil/RH side).

2 weeks ago ended engine works , fixed again coil and ballistor…try start…and smoke come
from ballistor+inside distributor too (wire from cover to contacts …“melted wire insulation”!)

i’m quite sure wires connection was the same , i have no removed this contacts next to coil or starting relay…

Perhaps during last 3 years accidentaly i have removed and bad refitted like you wrote!

Can paint work like insulation ? does exhist that coil/ballistor screws works like ground (-) contact ? Can failure come from paint insulation effect ? is a crazy think ?


You seem to be smoking a lot, Fred…:slight_smile:

‘Smoke’ are of two kinds; something (that should not be there) just evaporating from ‘normal’ hot surfaces - and something actual burning. With electrics; the latter means excessive current - a ‘short’, possibly caused by misconnections…

With any ignition system; no(!!) +12V must ever be connected to coil neg - coil neg is considered ground. if +12V is connected to coil ‘-’ something will surely burn.

The white wire from ign key (+12V), and eventual coil resistor in series, must(!) go to coil ‘+’. Check…

If you have done something wrong here; expect damage…

DIY painting certainly is no reliable method for insulation - but it may interfere with current flow if applied to connections. Also; electric components tends to heat up - and unless the paint used is heat resistant; 'smoke may appear…:slight_smile:

Again; does the engine actually crank…?

xj6 85 Sov Europe (UK/NZ)

Frank ,
smoked drugs when decided rebuild this car! :exploding_head:

I don’t know when/why but sure you’re right …coil wire inverted …

Ballistor first made smoke you’re ok again…was heated paint , smoke inside cap was cover wire.

New coil/cap/ballast/rotor remake cover wire …no smoke now but no light/spark.:sob: yes starter work.

Perhaps contacts broken too ? haven’t founded here this week.

Finally tested coil voltage , founded about 9 (key in 1) and during ignition(key in 2) don’t come a ballistor bypass 12V like forum users wrote.

perhaps all coming from starter relay ?

Time for unable Fred is over, willl call an able worker…foolish not call him first.

If you have mechanical points ignition, Fred; you need to inspect the wires inside the distributor - they may be burnt off. And check the points/points gap - there may be something there…

If you have electronic ignition; it’s quite possible that an electronic module is busted…

Connect a test lamp between coil neg and ground. With ign ‘on’ the test lamp should be fully lit - while cranking; the lamp should dim and flicker.

There is no shame in seeking professional help - with points ignition the set-up is sometimes complicated…

xj6 85 Sov Europe (UK/NZ)

With ign ‘on’, engine stopped and coil not grounded; you should read battery voltage(!) on coil pos, both ends of the resistor and coil neg. Lower voltage means that current is flowing - which it should not.

Voltages with engine running is dynamic - and oscillates very rapidly.

I got a chuckle as to “elephant’s nose”. A great term for the gaiters form the drain for the intake at the cowl.
In medical terms or religious, a miter valve. Our hearts have them!! Bishops wear a cap that looks like them.

As insulation, paint can be good or bad!!! Protecting a hot wire, no. Preventing a good ground connection, oh yes, do that well. Look at the battery ground, (-) at wing wall. Mine caused much travail…

As you have an interesting car, it might be time to 'go back to school". Mechanical shop class. Learn the function of things in the car. learn how that function is applied in your car. Electrical and mechanical .

Diagnostics are preceded by function knowledge.

Ignite the fuel in the combustion chamber. The function of the ignition system. Components, switch, wires, coil, perhaps a ballast and a distributor.

The distributor low voltage wires and much higher voltage wires. How the distributor and coil accomplish this for another time… Home work for Fred !!!



now is time for 2 relays, founded :

  1. 6ra on firewall starter 33231E 12v 4369
  2. 6ra on RH side next coil , horn ralay 33208(6?)9F12v2969

lost on sng barratt codes…can help me for correct buy ?

Some forum users tell about c33231 Others c.35884 for ballast type…Others tell about 22RA perhaps 36611…so i’m confused :woozy_face::pleading_face::scream:

what’s 2 correct codes?



Frank ,

leave this post and goahead with relays/diagram only.