Hello,


I've searched and found some good info about Petronix and other coils, and lots of info on XJSs, or older XJs or 6 cylinder XJs, but am still stuck on my specific issue.


Basic Questions:
1) On an 86 XJ12 (Canadian vehicle), should my ignition main coil be 6V (35C6) or 12V (22C12? or maybe HA12? or?)
2) Does anyone with a Series III XJ12 have feedback on changing from dual coils to a single coil DAC6093?
3) I notice the price on DAC6093 varies a lot. I want a quality part, but wonder if the price difference is due to quality, or if they are all from the same source and just marked up differently (ie buying from Jaguar vs from smaller retailer)


Background:
I had smoke coming out of my... XJ12's coil/distributor area. I unplugged the battery and removed the coil, and don't want to plug things back together until I know what's going on. I later found oil in my coil (35C6) tower, so it must have overheated. I've borrowed a couple of coils (described in question 1) from different XJ12 parts cars, but those coils are 12V. I don't know what part should be in my XJ since I don't trust the work done by previous owners on any of the three vehicles.


Thanks for your help,


ROD

 

I'm thinking 35C6 just becuase that's what's specified for the XJS V12 od similar vintage. I'm not aware of it being a 6 volt coil, though. Pretty sure it isn't.







Common, popular, works fine.





The original supplier for the DAC6093 was Ducellier as far as I know. Those are probably the more expensive ones you've seen. Others could be from a variety of manufacturers with the seller/distributor attaching the DAC6093 part number and calling it "OEM" just 'cause it looks like the original DAC6093. Sellers play it fast and loose with label engineering these days.






I'm not aware of any of the HE V12s with Lucas ignition using 6 volt coils. I believe the pre-HE V12s did, though.

The Lucas replacement is the DLB170 which is a 12v coil and I *think* it is now being sold in the DAC6093 configuration. IOW, if you order a DLB170, you'll get a 6093 style coil. Might not be the true 6093 but it'll be the 6093 style.



Cheers
DD

 

Hello Doug,

Thanks for the quick reply.

My british car mechanic (great with historical knowledge and old books, not so good with computers and tight schedules) told me the last two digits in the Lucas number specify voltage. If this is true, then


Jaguar service manual states (pages 05-5 to 05-6):
Pre-HE use 22C12 and 23C12 (12V?) depending on emissions
HE 35C6x2 (6V?)


Hayes states (page 112):
13C12 or 22C12, (12v?)


I don't see Canadian Emissions in my Jaguar Service Manual, but both my main and auxiliary Coils are 35C6.


I'm going to have to run a survey and check out other XJ12's when I see them...


ROD

 

Rod,

Misprints happen way too regularly in printed manuals, so common sense kicks in, for me at least.

The PreHE did run a "ballasted" coil, which is deemed a 6v unit, and that was due to teh huge ballast resistor pack bolted to teh throttle capstan. It incorporated a "by-pass" circuit, so that during the START mode that coil got a 12v jolt.

The HE arrived with a GM electronic system, very similar the USA Chev etc vehicles. The module INSIDE the amp unit controlled coil voltage (among other things) and YES, the early V12's of HE style had 2 coils. These were 12v "contact points" spec, of APP 1.2ohms each. When connected in the pair on the vehicle this gave APP 0.75ish ohms, which is the OHM that is compatible to that module.

As the coils age, the ohms rises, and eventually the module has a moment, and the engine stops. The engine cools, the module cools, the engine starts, and so on. At some stage the module fails.

These days coil technology has advanced in leaps and bounds, and single "Electronic" coils are plentiful.

I run a FuelMiser CC215 as a single coil on the HE's. They are APP 0.85ohms, and the coil and module are cool in all conditions, and the spark generated is FAT and BLUE, and gives the old ticker a jump start if I get careless.

Like you, I have seen a myriad of coils on the Jag engines over the years, due to us having the SAME mechanics as you, in that "coils is coils", or "looks like a coil, sparks like a coils, must be a coil" mentality.

The Duceliar mentioned is an excellent replacement, although I have never used it, due to prices down here being DUMB.

 

I have seen two types of people in my life. Some have powerful brains, the rest have to rely on common sense!, that is us.
You ever heard the saying "all brains,no common sense".