Cough, cough

[Orsom Weels]

Thanks chaps,
The Aldon unit is very similar the the Powerspark visually, I believe it is the same as the Petronix. I do recall someone having problems with them breaking down but I can't find the post now.
Robbie

There's been a few reports of Aldon failures, but I can't find them with a quick search either. I don't think they tolerate low battery voltage particularly well & they do seem to upset the original tacho's. Two out of the three I have known have failed, one of them very early in it's life, the third just keeps soldiering on. They have been replaced with powerspark units which seem to continue to work well also, & for the price of the Powerspark, it's not a lot of money tied up to keep a spare in stock just in case.
If your car runs hot, I think that will stress any electronic system though, so something with a remote module may give you the benefit of being able to locate it in a better environment.
I often wonder what makes some of our cars run hot, while others seem to keep their cool even in the hottest of weather. My own +2 still has the original narrow radiator & pathetic smiths electric fan & even when one of the wires got accidentally disconnected from the fan, it still just sat at about 85 degrees until I sat in a queue going into a show when I noticed the temp rise a bit, it still didn't boil or anything nasty. My Elan on the other hand has a wide radiator conversion, fans that would drag the space shuttle into orbit, extra vent cut outs under the bonnet & numerous other mods to aid cooling, but still it runs much hotter than the +2 & I can find nothing to explain it.

Regards, Tim

[john.p.clegg]

Robbie

https://www.ebay.co.uk/sch/i.html?_from ... or&_sop=15

John

[Robbie693]

Thanks John, yes that's what I was looking for but not seen anything even remotely resembling it so I was wondering if Rich had found something unusual in an odd place!

Tim, I too have pondered this one for a long time, in fact the old rad and original fan used to do the job almost as well as the new one! I have only one theory left, gleaned from an old post on here:

lotus-twincam-f39/washing-engine-block-after-boring-t36202.html?hilit=block%20cleaning#p248045

Regards

Robbie

[Chancer]

Thanks John, yes that's what I was looking for but not seen anything even remotely resembling it so I was wondering if Rich had found something unusual in an odd place!


Robbie

They are often built into the loom as a loop of resistance wire, on the Ford looms it would go up to the oil pressure switch and loop back, I know some Lotus looms used them but not the cable route.

A giveaway would be the extra cable to the coil "SW" terminal and from the solenoid, these may have been disconnected but the ballast resistor would still be there, another way is to measure the SW voltage when the engine is running.

Worse case scenario is that you have a ballasted coil running on 12v or a non ballasted coil running on 9v.

[Robbie693]

Thanks John, I do have another wire (yellow/white) off the solenoid but as far as I can tell it just goes straight to the coil...

These are old photo's and I've replaced the solenoid and the coil since but the wiring is the same. I used a 12V coil.

[Chancer]

That is the wiring layout for a ballasted coil, the wire from the solenoid to the coil is only switched when cranking.

With the ignition on and the CB terminal shorted to battery earth measure the voltage at the SW dual terminal, if its significantly less than 12v then you have a ballast resistor somewhere and the coil you fitted is incorrect.

If it is 12v then the wire from the solenoid to the coil does nothing and is redundant.

[William2]

I fitted the Powerspark module to my distributor about 1200 miles ago and so far it's been fine. A couple of points to note are that you must make sure the metal plate you are screwing it to is flat and that you use the heatsink compound between the mating surfaces. When I last spoke to Simon at Powerspark he said that he had only rarely heard of units that had failed. It's also very good value!

[Robbie693]

Thanks John, will check.

William - yes they said that to me too! They were very helpful and pleased to see an actual customer's car, Simon was convinced it was my coil but gave me a pre-tested module to try out. I also bought one of their Viper dry coils too. Sadly the coil on it's own didn't do the trick but the replacement module restored things. For a while... As I said, I'm not blaming the parts

Robbie

[RichC]

i never did find the resistor
multimeter reading told me something or other and the EI guy said there was resistance somewhere .
I'm no 'sparks' . but could it be that the ignition switch itself might be a cause of resistance ?
i know the wiring loom was gone over and new decent quality connectors were put on all over

[john.p.clegg]

Sometimes , the ballast resistor is a length of " wire" in the loom and is slightly thicker than normal , not easy to spot ...unless you know what you're looking for and have a meter..

John

[Chancer]

As per my previous postings

[Robbie693]

Thinking ahead - As I have already fitted a 12v coil, could I not just disconnect the wire that may or may not have a ballast resistor in it?

[mbell]

The ballast resistor will be in the main fed line that comes from the ignition switch via the tacho if there be is an in built one. If you remove that wire from the coil then you'll remove the power supply from the coil... So you'd need to wire a temp power source to test.

The second wire conects full battery voltage to the coil when the starter is engaged. That is the white/yellow (?) wire that goes to the coil from the solenoid.

[Robbie693]

Ok, thanks Mark. I thought the resistor was in the 'extra' wire

Robbie

[Robbie693]

Back again with more developments/tail chasing.

I bought a new Powerspark module just because I wanted to sort this out quickly (!), fitted it and promptly broke down again in the same fashion next time I was out. More for something to do than anything else I swapped the cap and leads for an old set and there was an immediate improvement and I haven't broken down since.

The original problem still persists though; pulling away on even the slightest incline leads to choking up, bogging down, me having to slip the clutch and blip the throttle and, if I try and accelerate through it, backfiring and spitting back. Even when underway any hills taken at less than 2000rpm feel like the engine is misfiring and lacking power.

So, I did a check for ballast resistors. First I put a multimeter on the positive side of the coil and earth as suggested in a Moss video, this gave me 12.5V (same as the battery). Then I did as John suggested and did the same test but with the negative side of the coil connected to earth, this gave me 10.8V. There is definitely some resistance in there but I'm not sure enough to suggest I have a ballast somewhere?

The symptoms could point to a failing coil, I measured the resistance while cold and it's 3.3 ohms or so, I've yet to try when it's hot. The coil is a dry type and is only 3 years/ 2000 miles old so I would have hoped it would have lasted longer, would my new found resistance in the circuit cause premature failure?

Regards to all

Robbie