Battery not charging

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Brunsdens
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Battery not charging

Post by Brunsdens »

I have a problem with the battery losing charge. I thought maybe the dynamo brushes may be worn but they were ok. I then replaced the dynamo but still have the same problem. The battery isn't charging. The red ignition light is very slightly glowing. This glows slightly more as the revs increase. There is no voltage increase at all. I have tested the new dynamo by bridging the terminals and get 15.5 v at tickover. If i increase the revs this goes down to 1v, but there is not any voltage increase above 12.5 at the battery. When the engine is running the battery voltage slowly decreases. I am at a total loss and would welcome any advice. I have read the manual but to no avail. It is a 1961, 948cc MM 1000 called Martha.
Last edited by Brunsdens on Sat Apr 11, 2009 7:56 pm, edited 2 times in total.
Brunsdens
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Post by Brunsdens »

Yvonne & Rob
PSL184
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Post by PSL184 »

I'm slightly worried that you are only getting 1v at a fast idle? Is that correct ???
The regulator contacts may have stuck together or need cleaning. Wires may be off the regulator. Poor connections to the battery or the regulator may need adjusting. Is it an old battery - it may be kippered? Try these then let us know what you find....
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Brunsdens
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Post by Brunsdens »

It is correct we are only getting 1v at fast idle. This is read from bridging the contacts on the new dynamo. I think the battery is still ok as it has held a charge for the last week. We only bought the car 1 week ago. I will check the contacts tomorrow and clean the connections and let you know. Thank you for the quick reply.
bmcecosse
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Post by bmcecosse »

Have you changed the polarity of the car ? If the dynamo is not same polarity as battery connections - it won't work. Take a wire lead from the non-earth connection of your battery - and spark it on the small dynamo connection a few times. Then run the engine -does it now charge ?
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Brunsdens
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Checks

Post by Brunsdens »

I have now cleaned all the connctions and still no joy. I followed the correct procedure for the polarity on the dynamo. I have put a temporary cable from each side of the dynamo to the regulator in case of cable breakage. Still no difference. It is possible I bought a faulty dynamo but how could I check that? I am at a total loss!!!!!!!!
mogbob
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Post by mogbob »

A reading of 1 volt would appear to indicate a "field winding fault" in your dynamo according to :-

http://freespace.virgin.net/tommy.sandham.dynamo.htm

Instructions on how to confirm this is given on the website.If the case is proved...it's back to the supplier that sold you the dynamo for a replacement.

Bob
Brunsdens
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tested dynamo

Post by Brunsdens »

We have now tested the dynamo and it is working OK. The reason why I was getting 1v was because the voltt meter was set at 20 as the revs increased the volt meter went to 1v. When I reset the volt meter to 200 we got a reading of 60volts as the revs increased.
My next course of action is to replace the regulator. I will keep you posted. What a bank holiday weekend!
PSL184
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Post by PSL184 »

Have you tried adjusting the output from the regulator?
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Brunsdens
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Regulator

Post by Brunsdens »

I havent tried that. Please could you tell me what to do, How to adjust the regulator? The car has only done very little mileage for the last few years (6 miles the last 18 months) but because I dont know any of the previous owners I cant say whether this has been an ongoing problem.
Thank you for your time.
bmcecosse
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Post by bmcecosse »

60 volts sounds a LOT!! I don't believe it!!
Easy way to charge the battery - start engine, connect the two terminals on the dynamo together - and connect a wire from these two to the non earth side of the battery - now rev up. What voltage do you get now - on the battery ?
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PSL184
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Post by PSL184 »

Section N.9 of the WSM tells you how. Ask bmc for a link to download it......
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LouiseM
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Post by LouiseM »

60 volts sounds a LOT!! I don't believe it!!

Our very own Victor Meldrew :lol:


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Brunsdens
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Post by Brunsdens »

Problem Solved !!!!!!

It was the regulator. We changed it for one off another minor we have and it worked.

hank you so much for all the help!!!!

Yvonne & Rob
bmcecosse
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Post by bmcecosse »

PM sent with Manual download.
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