Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Bosch ignition coil for a 1995 Plus 8

Hi gents,

I'm in need of a new ignition coil for my '95 Plus 8 3.9 with the 14CUX EMS. Seems that the Bosch 0221 122 392 (silver body with black plastic top) is impossible to find. I've even tried searching using the Land Rover part # as well as the TVR part # and nobody, literally, n-o-b-o-d-y has one available, which seems insane considering a fair few cars used this coil. So, am wondering if anyone has found a suitable alternative? There aren't *that* many different specifications of ignition coils so I have to assume there's something that people have successfully substituted in.

I have a few spare coils on my shelf, either 1.5 ohm or 3 ohm resistance, meant to be used on Triumphs and MGs. Does anyone happen to know if either of those would be suitable for the Mog?

Looks good. Or here .
I would not fit a random coil as the back emf can cause problems with the cap and arm if not matched.

Thanks Richard,

Called Famous Four. They had one. Appreciate the reference!

Aaron

With respect, why do you conclude that is your need?

There are many coils that will suit of course. Your sourcing difficulty is merely that, with programmed ignition systems of today, coil packs have taken over from coils. After all, how many 30 year ignition systems are still on the road? But there are plenty of coils that will suit. As for that specific model, manufacturers are always trying to standardize production. In the day, the goto coil for your car was Bosch Blue which are still available. Only watch point is which Bosch factory it comes from. Brazil and Germany are fine..Mexico is a no-no. I can make you a score of other suggestions https://simonbbc.com/ignition-coils/standard-3-ohm-coils/, but first read below.

You are safer trying your 3-3.5 ohm coil first. It is likely ballast resisted and these original LR/Rover ignition systems are delicate, very easy to damage. I have had a line-up of 1990s in my gomog Help Inbox. Do you have a separate ballast resistor or (shiver) a tiny little little beer can next to your coil? If the canister, (wrongly called either a "capacitor" or a "condenser" because of the way it looks) has gone south, the entire ignition system soon follows it...coil, amplifier, distributor... But the Help Line makes me worry too much. Ballast resistors fail VERY rarely. Take the little can and turn it over. Is the bottom rusted.

Considering all this, put in the 3 ohm coil you have. If it is still working after a couple of hundred miles, you can buy something newer. If it burns out, then you must delve further.

I cannot get too excited about coils. One does not get more of anything lighting a bonfire with a bigger match. Precision is more important. The original LR/Rover V8s (1967 through to GEMS 1996 for Overseas and 2000 for the UK) have substandard ignition systems. Quite amazing what happens when you swap in something better. Anything is better. We tested this stuff on an oscilloscope.

BTW, I consider the part of 1995 Plus 8 production the best Plus 8s ever made. Best combination of major components.

gmg

It’s a pleasure Aaron, the warning about the back emf comes from a highly respected Land Rover site I would follow their esteemed advice.
Good luck and wishing you many happy miles.

Richard,

As general rule....

While you cannot go far wrong with advice from a Land Rover site, it is harder getting things precisely right. Their versions
of the engines and management have different fueling maps, different cams, different needs and goals than a hyperlight sports cars
using the block. In fact, even our base ECU is a special version,whether L-Jet 1of3), Hotwire (1of14) or GEMS.(I can't remember),
merely a single odd one of very many. We even have special block numbers and ours weigh 1/3 theirs.In the 14CUX gamut
https://www.gomog.com/allmorgan/LRHotwireECUs.html Special sellers and expert literature advise different things for Morgans than
the heavy LRs. Of course, in this case it is merely a coil. In case of their ignition, they changed to GEMS 5-6 years before Morgan did
in the UK. 1995 was a transition year for them.

I would point to the TVR crowd as a guide but they begin with TVR factory/modified engines, ergo not exactly the same needs a ours.
Best to stick with Morgan people.

gmg

Their site has always sorted me out over 20 years now, as you say it’s a coil but as well to be aware of back emf with ECU tech.

I admit that I am easily confused, though the mention of ballast resistor takes me back to the seventies, when the ballast resistor in the coil circuit was used to reduce the voltage to the coil.

The design of the system was to assist the creation of a good spark at the plugs, while the engine was cranking and the battery perhaps under a bit of stress due to it`s age or attempting a Winter weather early morning start up...?

The ignition coil was generally circa 6 volts, and during cranking it was fed directly from the ignition switch terminal with whatever voltage the battery could supply which would only be live/hot only when the key was held against the spring in the start position.

In this situation the six volt coil (or thereabouts) was taking whatever voltage the battery could supply and thus very likely to create a good spark even if the battery was on it`s last legs, outputting reduced voltage due to the loading of the starter motor cranking a cold engine...

Even if the battery was capable of putting out circa 13 volts while cranking a hot engine, that the ign key would be held in the start position for a short period of time the coil would be more than capable of handling the over voltage it was receiving with no problem whatsoever...

The ballast resistor only comes into the circuit when the ign key is released and springs back into the run position (ign on) at which point the ballast resistor is now made live/hot from a different terminal in the ign switch the ballast resistor now made live, acts to drop the voltage passing through it to the coil to six volts or thereabouts, thus the voltage running through the coil is reduced to match the coil`s ideal voltage.

Without the ballast resistor the coil would overheat in time and fail..

A common complaint would be that the engine would fire up fine, but when the key was allowed to spring back into the run position, the engine would shut down. The next start attempt would just be a repeat of the first, generally indicating that the ballast resistor had failed, either it or the wiring to or from it had gone open circuit.

Generally whether the ign circuit had a ballast resistor, could be identified by finding two connections on the power in connection to the coil, having two wires connected as opposed to the usual single wire, one wire from the start position on the ign switch and the other from the run position on the ign switch through the ballast resistor and on to the same coil conection....

On some Fords, there was no ballast resistor as such, Ford used a length of resistive wire in the circuit which could be easily replaced within the engine bay if it failed..

As for capacitors/condensers, they tended to be fitted to inhibit radio interference.... Though by the time ECU`s came along I kinda lost interest. I would have thought that ECU manufacturers would not design kit that depended upon external capacitors fitted next to a coil to protect their innards..... might have thought some sort if internal opto isolation might have been designed in... Still as they say every day has potential to be a school day...?

BTW, I very much doubt if any of that which I have typed above would in any way be applicable to and 90`s built vehicle...

Just passing time, thinking in type.

As ever more than happy to be corrected where I get things wrong, as I oft times do...

No need to quote you Luddite. Your understanding precisely mirrors my own study and experience to a "T".

I am now up to my 6th sufferer with identical symptoms and cure. The first was referred to me by a very respected Morgan
dealer who was flummoxed. They know I enjoy pre-GEMS Plus 8 issues. The symptoms are the same. First a coil (2 or 3)
burns out. Then the amplifier, cap, rotor and last (but soon after) the dizzy itself. (which does not surprise me as the Lucas 35
series can fail if you stare at it hard (Kevin doing the testing). Thankfully, they have such a bad reputation that rebuilt one cost
very little.

All these models did NOT have a ballast resistor like our 1980s Plus 8s. https://www.gomog.com/allmorgan/Plus81977to1982.pdf
By the 1990s, they were using these little beer cans which different LR suppliers refer to as either a condenser or a capacitor
Everyone takes them as you do, something to clear up radio interference. But they don't. I found literature saying they reduce the
voltage at start up and then return to full voltage. In a nutshell.....

"Attached to the points, the condenser or capacitor stores the current temporarily to prevent the points from arcing and turn off the current faster. Ignition problems, an engine that won't fire, and rough running are symptoms of faulty points and a malfunctioning condenser." or google "land rover 1995 ignition condenser". The
description indicates a role far more important than clearer music from your radio.

LAST HINT, though, as you are aware, ballast resistors are almost bullet proof and inexpensive, these thingies cost less,
always a sucker feature for a manufacturer..even LR. I did not like the consequences of their well-hidden failure, no matter how
much money LR saved from the late 1980s to 1995. And in all cases I have seen, the failure of these little things spreads before
the correct diagnosis. I dislike that.

So I took the simple path. I have them removed and replaced with our ballast resistor. Nary a problem after and the owners feel
confident enough to take long trips. I like that.

L.

P.S. I have never had radio interference. You? I also use Magnecor Blacks ignition wires.

I would be equally if not more concerned with ensuring the coil was designed to work with a ballast resistor. Typically this would be a nominal 9 volt coil such that whilst engine cranking, the reduced battery volts better match those of coil to maintain a good spark during this critical phase. The ballast resistor coming into play after start and throughout normal running to reduce and so provide design voltage to coil. Fitting a more readily available 12 volt coil with the ballast resistor in circuit would leave the spark well below par.