Something electrical died

[SRK]

I've been getting my 1973 series 3 ready for inspection and all has been going well. (it sat for 8 years prior to me buying it) After fixing a number of things I've put at least 4 hrs of run time with no major issues. Yesterday the car ran fine; today when I went to start it, it sputtered for a while (never really running) and then completely died. First thing I check was fuel by giving it a few shots of ether and nothing happened. I then hooked up my timing light and found there is no spark. So something in the ignition system has died. Check fuses and they are all OK. I also looked at the schematic and see that it could be the ballas resistor, coil, ignition amp, or I guess something in the distributor. Before I start ordering a bunch of parts, anyone have an idea on what the culprit might be?

Mahalo (Thanks) in advance!!!

Steve from Hawaii

[Paul71a]

Start with the rotor arm. They're notorious!

[lundabo]

Are the rotor arms notorious on the Series III? I would just start going back in the system to see where you have spark. If you have a strong spark at the HT lead, look inside the distributor. IF it is weak, look back toward the amp, coil or ballast (though I would all upon those more learned than me to differentiate between Opus amp and coil). When my ballast went, the symptom was that the engine would crank and start, but immediately die as soon as I returned the key to run.

Note, more recently I have had problems where the car would die out of the blue...with an attendant drop of the tach needle to zero when it happened. Turns out to be rotting wire that is arcing and shorting on me.

[Dave123m]

Hi,

I had a similar problem with mine after being stood for 25 years.

It was fine for about 3 months with regular short duration starting & running to move it whilst it was being re-commissioned then it simply died & would not restart.

After extensive investigation my issue was faulty Opus Module (probably sat in the Vee just in front of the Distributor or maybe on the radiator panel depending on year) where the moisture had entered the box.

Unfortunately I don't think there is much you can do to service the original unit & you may need to use an XJS upgrade however I would strongly suggest checking this first.

Good luck.

Dave

[vee12eman]

Hi,
To back up what Dave said, the Opus ignition unit was always prone to failure, originally associated with high under bonnet temperatures but later with age, corrosion, water damage and the like.

There are various options if if goes wrong, ranging from a replacement s/h unit through replacement units which are visually indistinguishable from the original, to complete replacement using a replacement which does not pretend to be the original. I know little about the last option, other than that a Crane ignition unit is quite popular in Australia and may be available elsewhere.

S/h units are likely to be as unreliable as your original so a new unit is often the best course. Until recently there were two options, the SNG unit, still available as an exchange for your original and using a design from the later XJS version of the system, or alternatively, the ReOpus unit from Dave Curry in New Zealand. Dave recently went into semi-retirement so no longer supplies complete units, though he still supports previously supplied units. However, his excellent website is still available at:

http://www.reopusignition.com/

This site is a must for any V12 Jaguar owner with the Opus system (which includes all Series III E-types). It may help you to diagnose the fault.

The SNG unit has good reputation and is a good option, but as others have said, there are other things to check first, including the distributor cap, rotor arm, air gap (between sensor and magnetic impulse disc), leads, plugs, and connections.

Good luck diagnosing the problem.

Regards,

[SRK]

Paul, Bill, Dave and Simon, thanks for the quick responses. I've spend a few days reading posts and websites and also traded notes with Dave from ReOpus who confirmed he was no longer producing new units. After looking at the cost of the SNG unit it made real sense to change over to their system so I bought one today. Price seemed very reasonable ($625) after the core charge is removed. Only issue is I'll have to wait a few weeks since their on back-order. Not a big problem since I'm on the road now and will not get back to Hawaii until the end of May.

I have not opened the amplifier but the jag did sit in a garage about 200' from the Pacific Ocean for 20+ years and I do suspect it will like Dave's inside. Thanks again for the help!!!

Will let everyone know how it works after its installed.

Steve