Any thoughts on the reliability of positive ground electronic regulators that are used by Classic Regulator to convert a mechanical regulator?
I fitted a solid state regulator to my etype. The original regulator would fry the electronic ignition, so obviously had problems. It transformed the smoothness of the engine.
Been running with it for over two years now with regular trips to the continent without issue.
I have one inside the Lucas case in my XK120, it’s worked fine for two years. Including XK70 when we shipped the car to the UK. I just gutted the original regulator in my SS100 that I’m restoring, but I won’t have it on the road for a while. 
Simon. Thanks so much. It’s great to have someone to give you confidence to go ahead with a idea. Jack
I just saw your comments and picture. They make me confident to go ahead. Thanks. Jack
John
Just done the electronic regulator conversion inside the RB310 Lucas box.
My original was not pumping out enough at Idle and and at 2000 rpm, I now have 13.95 at 2000 rpm.
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Thanks. I’ve just made the move. Jack
Back again. Has anyone purchased a electronic regulator to replace a RF95 mechanical regulator from Advanced Dynamo Regulator in England?
I have just ordered an ADR from Classic Dynamo and Regulator Conversions in Lincolnshire, UK. They are expensive at over ÂŁ150, but I was convinced after reading what they had to say about the cheap Indian built alternatives. I could have had my existing regulator converted by them to solid-state, but that is more expensive than an all new one. You can order it without cover and clip if you want to retain your original ones.
After speaking with them I realised that my regulator is not functioning correctly, and is probably on its last legs. For instance, after churning away on the starter, say a dozen tries, you would expect the ammeter to show a healthy charge for a while once the engine is running, before settling down the centre zero on the gauge. In such circumstances mine shows only a very little charge and quickly settles at the centre position. Therefore, I deduce the batteries are not getting the charge they need, and every start is just discharging them a bit more each time.
I know the dynamo is putting out enough, because when I tried another regulator (which turned out be faulty) the charge showing on the ammeter would just go up with increase in revs until it was off the scale.
I’ll let you know how I get on.www.dynamoregulatorconversions.com
I should have said this is an ADR95 regulator, replacing the RF95 one on my XK120.
Chris Thanks for the background on your decision to try the ADR95. Haven’t made the decision yet but you have given me some confidence and I’m sure many others on the site are watching with interest. Also looking at a new mechanical regulator made by Holden in England for 129 pounds. I’m still a couple of years from completing my XK120 dhc so I have some time. John
Received my ADR95 from CDRC and it certainly seems a quality piece of kit. Here are some pics, minus the lid and clip - I’ll be using my original ones. I’m waiting for a day that is bearable temperature-wise to install it. It came with comprehensive instructions, including advice on how to polarise the dynamo, which is more of a precaution, really. Probably not necessay if the car has been running with positive earth (in my case) up till now. Definitely advisable if dynamo is an unknown quantity or has been changed.
As the weather was bearable today, I fitted the new solid state regulator. Fitting was straightforward. With my own cap and clip fitted it looks completely stock. I’m happy to say that it seems a big improvement! On start up, intial charge showing on the ammeter was well above 15 amps, but fairly soon came down to a steady 10 amps or so, indicating that the batteries were in a pretty low state of charge, I reckon. Anyway, the ammeter is behaving as I would expect and is a marked improvement on what it was showing with the old points-type regulator. I even think the engine seems to be running a bit more smoothly!
I have a quick question on this topic. Recently, I bought one of these small portable jump starters - I settled on an Audew after some research on YouTube etc. The (1 year old) 6v batteries in my 120 were sufficiently discharged so as to be unable to start the car, though the starter was turning the engine over. I fitted a WOSP gear-reduction starter a while back, but it never really sounded much different to the original starter when being operated, which I thought was a little strange…
So, I hooked up the mini jump starter - it has very short leads which won’'t go anywhere near stretching between the two batteries, so I hooked up the negative to the negative terminal of the first battery, and earthed the positive lead to the battery retaining clamp. As the jump starter was advertised as being able to start a 6.2 litre diesel, I was interested to see what it would do. I was relieved and a bit surprised when it spun the starter over like crazy, and the car started fine. I’d never heard the starter spin over like a maniac before! Why didn’t it behave like that with fully-charged batteries…??
I’m wondering how good the earth connection is from the other battery’s positive terminal. A previous owner had installed a cut-off switch on the vertical panel behind the passenger seat (the left one, as it’s RHD). I’m suspecting the earth contact is not all it might be with that switch, so I’ve ordered another one. I’d be interested to hear if anyone has any thoughts, and if they think I’m on the right track.
Thinking about it some more, I realise that if the jump starter spins the engine so vigorously, there can’t be much wrong with the earth through the cutout switch, as it would have been flowing through that anyway. Then I thought it might be a lack of earth from engine to chassis, but that would be the same deal. The only thing I can come up with is that the batteries are just not up to the job, even when fully charged… I really did want to retain the two 6v batteries for the sake of originality, but maybe I’m going to have to go with an Odyssey 12v or something. I just want to hear that starter spinning like a mad thing without the jump starter!
Hello Chrislackner - just wondering how “clean” are your connections between the batteries, since your test method bypassed the route through these connections - Tex Terry, II - 1991 XJS V12 Classic Coupe, 1986 XJS V12 Coupe - sent 1/20/2021 1435hrs. EST USA.
Tex, I had made up a new heavy-duty cable with soldered terminals connecting the two batteries, so no issues there, I think. In any case, when I hooked up the jump starter, the current would still have been flowing through both batteries. It’s just that I couldn’t reach the earth terminal on the other battery so earthed it directly to the body. It amounts to the same thing, doesn’t it?
Measure the voltage on the output of that jump starter pack. You might be surprised
Chris - when you connected the earth lead, of the jump pack, to the body, the path would be from body to engine block to starter case, which apparently must be very good - the existing earth battery lead, from the battery to wherever you have it, body or engine block may have some corrosion at the connection therefore may cause reduced flow to the starter case earth - this is why I made the suggestion - and, as Phil stated, the jump pack may well have more “power”, thereby getting through any “poor” connections better than your battery “power” - Tex Terry, II - 1991 XJS V12 Classic Coupe, 1986 XJD V12 Coupe - sent 1/20/2021 1908hrs. EST USA.
Good thought, Terry - worth checking out. Thanks!