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TR4/4A TR4A Charging system

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S

SBooth

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Now that it runs after an 18 yr. coma, I not getting anything out of the charging system.
I've been told that because of the relationship w/ the regulator, I won't get a true voltage reading by checking the generator output.
Can't find a local shop that can check the generator while it's off the car. Suggestions / instructions on trouble shooting the generator / regulator so I'm not replaceing good parts ?
Thanks !
 
The usual problem with generator output is worn or stuck carbon brushes. It is fairly easy once you have the generator out of the car to take off the pulley and fan, remove the "nose cap" and find two small blocks of carbon, spring loaded to make contact.
Often they are rusted or stuck in place or simply worn down too far.
Replace or free them up and you may solve the problem. There could also be some other problem which may be visible. Some of the wires on mine had got too hot from the exhaust manifold being close and the insulation cracked and fell off.
Good luck, Simon.
 
If you want to check the dynamo in the car then there is a directive in the Bently manual. You need an analog volt meter to do this. (maybe a digital will work...I haven't tried) Just connect the two terminals on the generator together , run the car and check the voltage. That's one lead to ground and one on the connected terminals. This check should last only a few seconds as the unit can generate around fifty volts but not for long.

Alan T
 
Since the car has been in an 18 year coma, it's quite possible that the pole shoes have lost their residual magnetism and the generator needs to be "polarized".

Here is a link that will tell you how to polarize a Lucas generator. be sure to read the links within the link I gave you, as it goes into more detail.
 
When I ran my car for the first time after a 25 year hibernation, all that I needed to do to get it charging again was to clean the corrosion from the contacts of the regulator with some emery paper.
 
[ QUOTE ]
The usual problem with generator output is worn or stuck carbon brushes. It is fairly easy once you have the generator out of the car to take off the pulley and fan, remove the "nose cap" and find two small blocks of carbon, spring loaded to make contact....

[/ QUOTE ]Uh, Simon, I'm pretty sure that the brushes are on the other (back) end of the generator, in that end plate. /ubbthreads/images/graemlins/smile.gif
 
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