Is there a visual difference?

[TheDampMan]

I wonder if you knowledgeable people can help.

Since owning the car (1 month) it has always been temperamental when starting (both hot and cold) also had a misfire once it got up to temperature at higher rpm, now it wont start at all.

Its getting fuel to the carbs which are in a good condition having recently been refurbished and balanced by the previous owner.

There is no spark at the plugs. My first thought was to upgrade the Ignition system (the kits are around £450) as the original system by all accounts is unreliable.
The previous owner spent a lot of money on the car, he told me the distributor and coil are new but he is unsure if it had the full conversion kit, so my question is are there any visual difference or identifying markings/numbers between the original Opus system (Distributor, Amplifier, Ballast resistor and coil) and the upgraded HE kit?

Any thoughts what to check for no HT spark?

Thanks
Steve

[jagwit]

Steve

Welcome to the forum!!

The best thing you can do is to get rid of anything and everything associated with the word "OPUS".

The cheapest solution is most likely to get the dissy, LUCAS ignition amplifier and the dual coils (getting BOTH coils is important) from a V12 HE engine. I recently installed this exact setup on an E-type and it works beautifully. This solution also gets rid of that stupid timing retard system the V12 was cursed with (compliments of emissions regulations).

I have the dissy's vacuum advance connected to permanent vacuum on my own car as well as this car with the HE ignition system with perfect results.

My own car is equipped with a Lumenition system by the previous owner after he had trouble with the REOPUS system the owner before him installed.

Regarding your existing hardware, most important is to check that you have 12V coming in on the White wire connected to the ballast resistor - when the ignition is on.

Just one more thing. If the spark plugs are seriously fouled (black), it may LOOK as if no spark gets to them. Best is to install a new spark plug on the wire you are checking with and letting it rest on the block somewhere. If you then get spark, next step would be to replace all the spark plugs and then, if she starts, the next step would be to make sure that the engine is not running overly rich (black smoke coming out exhaust), as this would foul the spark plugs again(within minutes).

Once you have the ignition system sorted, you can look at the rest. Checking that the thermostats close the bypass route when hot is next on the list, then checking that the fans come on, etc, etc, etc.

[lowact]

G’day Steve. Here is copy of my service manual.
https://1drv.ms/b/s!AiSPBKa26IcchJoGD2wp_dEgALSoQA
Section 86.35 is the Opus Ignition system, it will help you to id if it is original or modded. The absolute tell-tails are:
• The design of the ignition amplifier
• The THREE wires (red, black, yellow) connecting the ignition amplifier to the distributor
• The design of the “electronic timing rotor” inside the distributor.
Also in this service manual are the tests to be carried out in order to verify the condition/performance of your Opus ignition system components.
There are four main reasons why the Opus ignition system can be unreliable.
The first Is not a fault of the ignition system, after 40 years wiring becomes brittle and cracks. The main culprit is, as Phil says, the wires that supply power to the ignition system, where they emerge from the wiring loom and plug into the ballast resistor. The white wire (provides power when driving) is from the ignition switch and connects to the “SW” terminal. The white wire with the blue trace (provides power when starting) is from the starter solenoid and connects to the “START” terminal on the ballast resistor. BEFORE doing any other test, give each of these a firm tug and a shake. If they break off, there’s half your problem.
The second potential problem is the coil, the new coil may by the wrong one, is supposed to have a primary resistance of not more than one ohm. Mine has 1.4 ohm but I get by. As per the tests above, measure the resistance between the two screw terminals on the coil (don’t have to turn on or disconnect anything) If the resistance is too high yr spark will be very weak or missing ... The wrong coil can also, over time, overstress the electronics in the amp and the distributor.
The 3rd problem is the location of the ignition amplifier. As shown in the above service manual earliest cars had this in the vee next to the distributor, where they got cooked. Jaguar quickly changed this to mounted on the cross-bar under the cooling water expansion tank, solved this over-heating problem. If yr amplifier has been cooked (fails the above tests), no probs, these are easily fixed, very basic circuit inside, take the amplifier down to yr local electronics shop, tell them to replace any components that seem sus ...
The 4th is basic, the distributor cap and or high tensile rotor is dirty, cracked, worn. I note the DPO says the distributor is new but ???
For further info here is an old copy of Kirby Palm’s “Experience in a Book” for XJS’s but also applicable to E’s, especially the comprehensive section on the Lucas (Opus and CEI) ignition systems.
https://1drv.ms/b/s!AiSPBKa26IcchJgyI0COwjxZnCBnmQ
Good luck, have fun.

[TheDampMan]

Thank you both for the help, as I plan to keep the car I want to make it as reliable as possible so have decided to invest in new ignition Conversion Kit.
Thanks again
Steve

[lowact]

No worries, just be aware that the SNGB upgrade from Opus to CEI (HE system) is electrics only, the vacuum system, retard or advance, will be the same as you have now UNLESS you very specifically asked for this to be different ...