Antonnick Posted August 2, 2023 Share Posted August 2, 2023 Just reinstalled the Dynamo and the test . This time I increased the revs and sure enough the voltage climbed to 16V or more. So does that mean that the Dynamo is working as it should? From the Triumph manual ( I still cannot find this section in the Workshop manual) it mentions 730 rpm - this is tickover speed. Could it be that 1730 is meant? Quote Link to comment Share on other sites More sharing options...
glang Posted August 2, 2023 Share Posted August 2, 2023 Good, yes I think the revs is an error so as long as the voltage came up quickly and was steady, its working. However have you still got a problem? If so its either the wiring or the regulator... Im using the Vitesse/GT6 manual (has a really good section on the generator and regulator) and think it must also be in the Herald one somewhere but there might be some differences.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 2, 2023 Share Posted August 2, 2023 I have previously checked the wiring for continuity which seems to be ok. Perhaps I should redo the test with the wiring in place at the Dynamo but using the wires pulled off the control box, just to make sure. Have taken the battery out and put it oncharge now overnight. Tomorrow I will use the spare control box I have and see what happens. Quote Link to comment Share on other sites More sharing options...
glang Posted August 2, 2023 Share Posted August 2, 2023 No chance the problem has already been fixed by the dynamo overhaul? Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 2, 2023 Share Posted August 2, 2023 (edited) Nein - I did not check at the battery but the ignition warning light still shines brightly after I reconnected all the wiring and restarted the engine. Edited August 2, 2023 by Antonnick Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 3, 2023 Share Posted August 3, 2023 The plot thickens. This morning I did the F_D connection at the end of the wires , having removed them from the control box, ran the engine and got as before 18V +. So I am assuming the Geny is working. Reconnected the wires to teh control box, ran engine - ignition light stays on.# I did think I had a new after market control box to try out but in my chaos I cannot find it -perhaps I was dreaming. I do have an old one that I took off and so I have installed it to try out. At first , after the engine started, the ignition light flickered as the revs increased, it never completly extinguished but at least was not glowing red as the previous box did. I thought it might be worth cleaning the contacts, so disconnected the battery, cleaned up with emery paper, reconnected battery and started the engine. Back to square one - red light on all the time......... But I wonder, with the flickering, is that an indication of something? Quote Link to comment Share on other sites More sharing options...
glang Posted August 3, 2023 Share Posted August 3, 2023 I assume youve got the same RB340 regulator as fitted to the Vitesse (3 coils in a row inside the black case)? With the ignition off and wires D and F disconnected at the regulator measure resistance across these two terminals. You are measuring across the voltage and current control contacts both of which are closed so resistance should be zero. These contacts supply power from dynamo D to its field F the same as when you did the short test earlier so if not closed will result in insufficient dynamo output.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 3, 2023 Share Posted August 3, 2023 No I have the two coil RB 106 fitted. But I will measure this resistance and report back. Quote Link to comment Share on other sites More sharing options...
glang Posted August 3, 2023 Share Posted August 3, 2023 Ok yes the same measurement is valid but you'll be measuring just the voltage control contact resistance as your regulator doesnt have a current control facility... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 Good morning Glang. I measured just now , with all wires disconnected to be sure and the multimeter measured 65 ohm resistance from the D to F terminal tags. If this is supposed to be zero Ohm, then perhaps this is the root cause problem? I notice inside the control box, normally out of sight, there is a sort of "bus bar" connecting the F and D terminals. Do you know of its function and perhaps that is the fault? Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 This is the problem because current isnt getting to the field winding of the dynamo so it cant increase its output (the 65ohms is the resistor across the contact to reduce sparking). Here is the diagram and as you can see from D to F is a direct connection through contact 4 which should always be closed until the dynamo volts get too high. Im guessing that even though youve cleaned the contact it still has a high resistance and Ive struggled with this before because for some reason they refuse to stay clean. I wonder if they have a coating that wears off (the manual says cleaning them must be very gentle) with use and then the under metal oxidises easily so that the problem returns... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 Forgive my confusion. Are you saying that the 65ohm that I measured is ok as it represents an in-built resistor which is there to reduce sparking? Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 no when the contact is closed, as it should be all the time until theres too much voltage, the resistance will be zero but when it opens the reading wont go to infinity because of the resistor as you have measured. By hand you can try holding the contacts together better and I think the resistance reading of D to F will go to zero.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 The "contact" you refer to I assume is the cut-out coil of the two? The 65ohm measurement I get is there whether the contact is open or closed, it makes no difference. Is that good or bad? Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 there should one contact closed all the time (voltage control) and the other open all the time (cut out contact). The voltage control is the first and its the coil on the left when the terminals are facing you - its resistance reading should be zero... Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 If you put a bit of pressure on its lower contact plate to make better contact the reading should go to zero.... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 OK, we are getting there. thankyou for your perserverence. As before the resistance between F and D terminal tags is 65 ohm regardless of whether the voltage reg is open or closed. i have also measured the resistance directly across the top of the voltage control coil. That also records 65 ohm. This indicates to me that the contact is not clean. I have the whole control box out of the car in front of me. I will now try to clean between the points again and report back. Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 yes you could try just sliding paper between the contacts on maybe clean them with alcohol but as I say Ive had problems before and although you can adjust the contact pressure that might then change the voltage setting of the regulator😯 Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 Soooo, after running the fine emery paper through, the resistance has gone! Not totally - the meter records 6 ohm and buzzes, indicating a good connection Is this now possibly the solution and I should put it back in the car? Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 I would like to see practically zero ohms so have you cleaned all dust etc off? If so give it a try and you should certainly get some output from the dynamo now🤞 Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 Glang, you are brilliant! I reinstalled the control box and after brushing away any dust with an old clean toothbrush, the reading was still not zero but only 1,5 ohm. As good as. I then started the engine. Ignition light goes out - the cut out can be seen to function - the battery has over 13 V with the engine running. I call that a success - thanks to you. Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 Hey glad it worked! Hopefully regular use will keep the contact clean but if the ignition light does come up again you'll know the first place to look👍 Quote Link to comment Share on other sites More sharing options...
daver clasper Posted August 4, 2023 Share Posted August 4, 2023 Glad you got there. Regarding the dynamo testing. I got the same lower voltage figures at low RPM on 3 dynamos (this testing info appears on a number of info sources). Replaced the control box and been charging fine since. Ah well, at least Iv'e got 2 spare dynamos, that I'll probably never need. Quote Link to comment Share on other sites More sharing options...
glang Posted August 4, 2023 Share Posted August 4, 2023 Yes the dynamos are pretty bomb proof, the brushes seem to last for ages and of course the commutator even longer. However the front bearing might be the weakest spot especially if the belt is over tightened as it cant be lubed and is quite exposed to the elements... Quote Link to comment Share on other sites More sharing options...
Antonnick Posted August 4, 2023 Share Posted August 4, 2023 Not as glad as I am daver clasper. 😃 I had stumbled on to your thread when I got this problem and was consoled that the figures at low revs were similar to mine. According to Moss though you should get 16V or more at idle which is clearly wrong. I was never really 100% sure that the Dynamo was ok until Glang gave me the tip of measureing resistance on the regulator and indeed in giving the contacts a good wipe with emery paper. Before I had only lightly wiped it. It seems you have to be more forceful than recommended in the manual. Now , when the rain stops it will be time to enjoy the car again! Quote Link to comment Share on other sites More sharing options...
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