I was having problems with my Flamethrower coil and Pertronix electronic Ignition, both only 7 months old.
It turned out that the Module in the ignition and the coil were faulty and now replaced the car runs fine,,,,,However..
I spoke to Martin at Distributor doctor here in the UK and he recommended two routes to take.
Firstly use a rebuilt Lucas 45D6 distributor with the Pertronix internals as the actual distributor that Pertronix uses is of poor quality made in china with inferior components.
The second is to use a rebuilt Lucas 22D6 but return to points and condenser, apparently this is a better Distributor than the 45D6 but doesn't accept the Electronic internals. His personal recommendation.
He supplies JD Classics with his rebuilt 22D6 distributors for there racing cars with no problems.
Also Thunderroad Speedshop who work on my car but who specialize in AC Cobras said they would always choose a points and condenser distributor over electronic if at all possible.
I am happy to return to a points setup (and think I probably will) but don't want to be taking a step backwards and wondered what others opinions were on the subject.
There is no right or wrong answer here just opinions.

Cheers all.......

 

Glad to see you got things sorted... From another thread...

I've returned to points on all my vehicles; that had points.
I think I just had bad luck, but the electronic modules eventually failed and the one that did left me stranded, it cost a 150.00$ to get it towed home.
That was a Lumenition unit, I think heat killed that one.

Others here will attest that the Pertronix units are reliable where decades have gone by with trouble free operation.

I think the problem is you never know where parts are sourced, you can have a good batch which will be reliable or a bad one, there is no way of knowing.

My advice to you is that if you go aftermarket, then carry the tools and points to install them back in, in case the electronic stuff fails and hope that it doesn't happen at night in a rain storm.

That's interesting that Thunderroad speed shop goes with points if possible.
Two disadvantages with points in high revving engines, one is called point float, this is where the engine is going so fast that the return spring can't properly close the points and you loose full voltage saturation of the coil, this causes a weak spark at high speeds.
The other problem is similar, again, the engine is going so fast the points don't stay closed long enough to saturate the coil with voltage, this also causes a weak spark and even miss-firing.
They over came this with a duel point set up, but you still had the point float problem.
Of course the electronic modules don't have this problem.
With that said, unless you're racing your Jag, going with an electronic module is a waste of time (just my opinion).
No one drives their Jag faster the 70 or 80 mph, at least I don't.
Points have been around for a very long time, they are not that unreliable to warrant going to electronic.

 

Hi JeffR1 and thanks for that.
I have heard from most people that the Pertronix are actually very good it is just the build quality is pretty poor, the Flamethrower coils in particular are considered some of the best on the market.
Thing is when the Module had failed ,from that previous thread, I had no way of testing or doing anything about it apart from sending it away to be tested and replaced, at least a points system can be easily replaced at home.
I am still undecided and will talk to Martin again in a couple of weeks.
I know that everybody seems to love the electronic ignitions but strange that the people I have spoken too that deal with them for a living wouldn't use them if they didn't need to.
When the coil was on the cylinder head it was untouchable from the heat after about 20 mins, now the coil is moved to the inner wing between the rad and brake fluid it is cool enough to handle even after a long drive which helps a lot.

 

Points/condenser distributors are reliable, but will gradually deteriorate then finally fail on you, but you'll likely have noticed the deterioration well before then and done something about it (assuming you're a prudent type !). Electronic distributors give consistent performance above that of points/condenser but can suffer failure without any warning. Of course, as we all know, no manufacturers use distributors any more, and the reliability of the engine control systems is excellent, handling ignition and fuel supply in one box. Trouble is you can't fit these to your old classic Jaguar ! I suspect this is a problem of the after-market products being built down to a price and most suppliers being unable to support the degree of testing needed to support the product in the market. Some will be better than others, no doubt.

 

Testing an electronic module is difficult, it can bench test OK, but fail or give misfires when it gets hot from the engine bay, just like a weak coil.
Jaguar did move the coil down there on some models, but I can't remember what they were, it's a much better location, plus yon can run an oil filled coil because it can be mounted in the upright position.

I'm not sure what it was and the British with their weird coil mounting practices. The coils on my 51 Bentley are mounted up side down and they leak this black tarry ooze out the high tension lead when they get really hot. When I took one apart, they were built like an old transformer with this hardened tar crap on the inside.
The Silver Shadows had them mounted on their side too, it's as if they wanted them to leak.

I plan on putting this coil in my Bentley.

Retro Ignition 12 volt sports coil push-in HT fitting. Made in the UK

There have been problems with new solid state ignitions too, one example is that Ford had a premature failure in their ignition blocks on the Rangers in certain years, I'm sure there are other examples.
The other problem with points is they require maintenance and it's not easy to change them, I just pull the whole distributor out.
I found it easier to simply retime the engine, then contorting my arms down there, and I no matter how carful I am, I always drop that little washer down inside the distributor.

 

On a stock engine the points are adequate. The primary advantage with the electronic ignition is reduced maintenance. If the eninge is modified for higher power (especially at higher RPM) the points type ignition shows its weaknesses.
I have used the Pertonix on my Datsun 240Z cars with no issues at all and like my resto-mod Jaguar, I have put a ton of miles on those Z cars all with Pertronix internal upgrade.. Also the majority of Datsun classic 240z's, etc. are using the Pertonix internals but are using the Datsun distributor or a Mallory distributor. This way of using the Pertronix is done by hundreds of Datsun Z cars with very few instances of issues and when issues are posted at forums they were due typically due to miswiring. My opinion would be to use his first recommendation as that seems to match what hundreds of Datsun owners have done on all the forums and all the shops I know. Very few Datsun owners are using points on their street cars as the electronic conversion is super reliable but they used for the most part the Datsun OEM distributor.

 

I am unable to get spark to cylinders 4 and 6 after fitting new Petronix electronic points, their coil and their leads. Confirmed this is the case by using both a timing light and an inline light on all plug leads to check. All other cylinders run fine and the car starts but obviously rough. I did fit a new distributor cap with push fit connections as I didn't trust the acorn style screw cap to get the message to the spark plugs. Certain I cannot be the only person to have come across this problem and at the point of changing back to points and condenser or even buying a new distributor. One other point to mention is that this whole scenario began when the car would not start one day. Further investigation found that the keyway on the rotor arm had broken and decided to fit everything new as described above. Car is a 1965 Mk 2 3.8 litre 9:1 ratio with only 50K original miles and positive ground.

 

Install the original points and condenser back in to eliminate the electronic unit is a possible cause.
Do only this, if you change more then one thing out, you'll never really find out what is faulty.

If installing the points back in still does not solve the problem, then you may assume that leads for 4 and 6 are bad.
They should measure at around 10 to 50k ohms.
This assumes you're running resistor wires.

My gut tells me you have a faulty Pertronix unit.
At this point it's unlikely it's the coil as you have spark to the other cylinders.
Note too that it should be a 3 ohm coil.

EDIT:
Make sure there 6 little magnets in the magnet ring _ check with a paper clip.

 

Thanks very much for the help. I will get these checks done. As unsure if the old original points and condenser were the original problem I have just ordered new rotor, condenser and points from Barratts along with a push in lead style cap and an acorn style cap plus new leads. Will fit the push in style cap first with the Petronix leads just to make sure that is not the problem. Will then do your checks but my gut feeling is the same as you that the Petronix is faulty. Already checked the magnets with a paperclip previously and the leads tested okay earlier this week and I even swopped lead 5 for 6 as I knew it was good. Having these problems gets you learning new things. Reading the thread above there seems to be problems with electronic ignitions and I will be fine going back to original and checking the points regularly. If you have any knowledge on the correct way to attach the plug leads on the acorn style cap that would be useful as not sure if they should be soldered or not. Thanks again for the help.

 

I've never actually seen the wires soldered when using the acorn caps.
There is a special brass (sometimes nickel plated) washer with a tiny hole in it just to get the wire though (it's designed for solid wires).
The wires are then bent down in an even circumference all around the hole to form a 360 degree fan wires.
When screwed in place with the acorn fitting it secures the fanned out wires hard up against the brass nipple in the top of the distributor cap on each one.

If and or when you go back to points, don't get too obsessed with checking them _ once a year is plenty.

 

Thank you very much, this helps a lot as have tried finding the method online with no success. Will update if your suggestions above remedy the situation probably next week once parts arrive.

 

If you can borrow an Oscilloscope, you can check the low tension side of the Coil to determine if the electronic ignition is at fault or if it lies on the HT side, you will see only 4 spikes rather than 6 if the Pertronix is at fault (well you will see the gaps where the spikes should be is probably more accurate)

 

Everyone, I have good news !!! Finally I will be able to drive my car again this weekend !!!

Posting three photographs.

Picture 1 is the glass of Balvenie 15 year sherry cask malt I'm drinking to celebrate.

Picture 2 is the disintegrated Petronix magnetic ring I found when I decided to rotate to confirm I would not get spark on two different cylinders other than 4 and 6 (and also double check there were actually 6 magnets in there as suggested above).

Picture 3 is of the new wiring set and points just received from SNG Barratt that I will be fitted as soon as possible.

No trust in Petronix any more. Fitted a second magnetic ring that I had them send to me after I thought the first one was 30 degrees out. Started and sparking on all 6 cylinders immediately but fully expect this ring to do the same. No part numbers or marking on these rings which are apparently made in China and there is some chance that the incorrect rings for different distributors get stored in the wrong bins.

Thank You to everyone for your input on this and my other post about body numbers on steel sunroof Mk 2's.

This is by far the best Jaguar Forum with extremely passionate and knowledgeable members.

Thanks again.

 

Way too much ice in that drink! I smile at all of these posts. My fleet is totally original and they always fire and run. Many "upgrades' are in fact just new problems!

 

Thanks George, it melts pretty fast out here in Houston and 100% with you on keeping things original. That's what will be happening and pleased to see we have some entertainment value for you

 

sorry you had such a bad experience with Petronix. I have a similar setup on two of my Datsun 240Z cars and they have been very reliable over the last 15 years with no issues at all. You are the first person I have heard that had issues like that. From Z car groups the results have been very good with Pertonix and there are much more users on those forums compared to this site without any issues with that conversion.

 

 

I have just had an original Lucas 22D6 distributor rebuilt and now gone back to quality points and condenser. The Pertronix unit that I had for 7 months needed a new rotor after only two months, the module failed which to be honest was down to me incorrectly wiring it which is a big no no with these, then I noticed the cap had broken where the springs clips onto it. After speaking to several people including the engine builder for Aston Martin specialists R.S.Williams they all prefer to use points over electronic so decided to go back to the original set-up. It seems that the Pertronix electronic module and Flamethrower coil are highly regarded as reliable but the build quality of the distributor is extremely poor which I can actually agree with. Martin from Distributor Doctor couldn't plot an accurate curve from my old Pertronix unit as the shaft was loose in the top bearing, even after removing and oiling. Not what you expect after only 7 months and 2000 miles. So the answer seems to be get your old distributor rebuilt but with the Pertronix module, or get quality points, condenser and rotor arm. Will let you all know how it goes after fitting tomorrow.

 

I use the Pertronix unit in a rebuilt Lucas 22D6 distributor, Positive earth & debranded satin chrome Flamethrower coil. All fine thus far. I have friends that have had them for many years. Everyone warns not to leave the ignition on with the engine not running for long life. Old wives tale? I don't know.

 

Not a wives tale.
If one of the magnets on the rotor is in the right position, too much current will flow through the coil and cook it.
This will also damage the Pertronix unit.

When my dad was teaching high school mechanics, a student left the ignition on in one of the labs while the points just happened to be in the closed position.
After lunch, it was discovered that the coil over heated so much, the top blew off and wedged itself in the ceiling.
Take note that the shop had a 20 foot ceiling too.