Richardtr3a Posted August 12, 2007 Report Share Posted August 12, 2007 I seem to remember that it is necessary to polarise the new dynamo before fitting to the car. Is this cirrect and does any one know the procedure. I am still struggling with my electrical problems. Why is the fragile end of the dynamo jammed up against the exhaust so that the wires get hot, and is there anything we can do about it. My terminals are showing signs of melting. Any help would be apreciated. Richard Quote Link to post Share on other sites
Steve R Posted August 12, 2007 Report Share Posted August 12, 2007 Richard To re-polarize the generator, connect a jumper wire from the small terminal on the generator and touch it several times to the positive side of the battery. You will see a small spark. The generator's magnetic field is now polarized. You can now re-connect it. Did you run new wires from the dynamo to the regulator? I've had them cause a problem, I suspect they fused together in the harness and caused the sort of problem you described in an earlier thread. Steve R Quote Link to post Share on other sites
Richardtr3a Posted August 12, 2007 Author Report Share Posted August 12, 2007 I have run two new wires to the lod dynamo and the situation improved straight away. However the small cable at the dynamo end is damaged and I have a spare unit so that is going in tomorrow. My car is positive earth and are your instructions correct for positive earth. There does not seem to be anything in the manual about the polarity issue. Thank you Richard Quote Link to post Share on other sites
Steve R Posted August 13, 2007 Report Share Posted August 13, 2007 Hi Richard You just have to touch the wire from the small terminal to the negative side of the battery. Keep at it, You'll get there. Steve R Quote Link to post Share on other sites
Richardtr3a Posted August 22, 2007 Author Report Share Posted August 22, 2007 I have spent the evening fitting a recon dynamo and the new cables to the regulator. At first the ammeter needle jumped around a lot. I fitted a new Durite regulator and it went to full discharge on the ammeter. Then it refused to close the points on the new cut out at all. I put the old unit back and now the needle is steady but you have to rev to 3000 to extinguish the light and if you put the headlamps on the needle slips over to discharge even at high revs. Shall I attempt an adjustment or buy more units. All the contacts are clean and my back is aching from bending over the engine bay. Has anyone successfully adjusted one of these units at home? I remember why I made friends with the local garage when I lived in a village. Any help gratefully received. Richard Quote Link to post Share on other sites
stuart Posted August 23, 2007 Report Share Posted August 23, 2007 I have spent the evening fitting a recon dynamo and the new cables to the regulator. At first the ammeter needle jumped around a lot. I fitted a new Durite regulator and it went to full discharge on the ammeter. Then it refused to close the points on the new cut out at all. I put the old unit back and now the needle is steady but you have to rev to 3000 to extinguish the light and if you put the headlamps on the needle slips over to discharge even at high revs. Shall I attempt an adjustment or buy more units. All the contacts are clean and my back is aching from bending over the engine bay. Has anyone successfully adjusted one of these units at home? I remember why I made friends with the local garage when I lived in a village. Any help gratefully received. Richard Richard Try and repolarise the dynamo first of all as it sounds as if there is no charge coming from the dynamo. When the ammeter went full scale discharge that was a dead short so it sounds like that Durite unit isnt any good. If you do a search on here you will find information on adjustment of control boxes. A lot of the repro ones around arent very good. Stuart. Quote Link to post Share on other sites
Richardtr3a Posted August 23, 2007 Author Report Share Posted August 23, 2007 I have bought a moving coil ammeter and have the manual. I am nervous about adjusting a control box and hoped that full scale renewal of the two units and connecting cables would get me out of trouble. This is getting very long winded. Thank you for your help. Quote Link to post Share on other sites
stuart Posted August 23, 2007 Report Share Posted August 23, 2007 I have bought a moving coil ammeter and have the manual. I am nervous about adjusting a control box and hoped that full scale renewal of the two units and connecting cables would get me out of trouble. This is getting very long winded. Thank you for your help. Richard if you need more help give the workshop a ring on 01726 882680 and I will try and talk you through it. Stuart. Quote Link to post Share on other sites
Richardtr3a Posted August 24, 2007 Author Report Share Posted August 24, 2007 In my collection of 11 control boxes I have genuine Lucas , green box Lucas, reproduction, B90 nos dated 1988 and 1977,new Durite and others. Last week I bought a second hand box from e bay for £3.00. It is very dirty outside and comes from a Triumph Herald. I fitted it last night and now everything is just as it should be. I am very pleased because this now allows me to test all the other stock and identify if they work or not. The date on my old box is 1964. This kit is 43 years old and works immediately with a nice steady ammeter needle. I am becoming obsessed by this subject and will now spend months checking the ammeter instead of watching for speed traps. Can fitting a duff control box upset my new Dynamo? Thank you to all who have helped. Quote Link to post Share on other sites
Steve R Posted August 24, 2007 Report Share Posted August 24, 2007 Well done! and just in time for the bank holiday. I don't know if you can damage the dynamo with a duff regulator, one source I've found suggests you can. This source http://www.starautoelectric.com/Technical.htm says you also need to repolarise the regulator. 11 duff units seems a bit much! Steve R Quote Link to post Share on other sites
Richardtr3a Posted August 24, 2007 Author Report Share Posted August 24, 2007 This is a very useful website and I will be sending them some questions. I have never polarised the control box but will certainly do so in future. Thank you. Quote Link to post Share on other sites
Richardtr3a Posted August 29, 2007 Author Report Share Posted August 29, 2007 I am sure that there a lot of people out there who have fitted a new control box. The question is does every one polarise the control box as well as the dynamo. I am getting advice from an expert that it is essential. This could be my main problem. Also there is a motorcycle web site who claim that the control box is built for either positive earth or negative. Does anyone know the specification for the Lucas RB106/2 Quote Link to post Share on other sites
Richardtr3a Posted September 2, 2007 Author Report Share Posted September 2, 2007 I have been taking advice from different sources and it may be that the quality of the dynamos which I have been fitting is not good enough. When I went to the distributor Doctor and spent heavily I achieved a great result and the car starts first time hot or cold for the first time in many years. So I am now having a correct C39 PV/2 dynamo specially built for me by Bernard Bryant and a matching Control box to be delivered to Beaulieu next weekend. The dynamo as fitted is a C40/1. It does not look as if there is much difference but I would be interested to know. Has any one any experience in this area. How is it possible to identify new field coils so that I can make sure that I am not been fobbed off with some old parts? Quote Link to post Share on other sites
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