450SL 107 Charging Voltage

Isdyldan

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Joined
Dec 9, 2008
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Location
Woking, UK
Your Mercedes
'71 350 SL, Mercedes 350 CLS SB, '94 Shogun 2.8 LWB, '73 Porsche 914
Hi - I've been having flat battery issues on my '72 450 SL. I have fitted a new battery and with the engine off it shows 12.7 Volts. With the engine running I have 13 Volts at the battery and the alternator. I swapped out the alternator and the regulator for replacement (not new - off the breaking wreck I have) but still the same. Someone told me that this is fine for this car due to the sensitive D-Jetronic injection system, but I have read elsewhere that a battery needs between 14.3 and 14.8 Volts to charge properly. Any ideas please? Incidently, the rev counter has started bouncing around the place and the indicaters have stopped indicating, but these could be unrelated!
 

television

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Is.8 or a touch more or the battery will not charge at all, the reg packs are under 320 from Bosch and thats all there is too it unless you have a very bad grounding on the battery.

Rev counter also point to a bad ground somewhere, possible engine ground
 
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I

Isdyldan

Senior Member
Joined
Dec 9, 2008
Messages
263
Reaction score
12
Location
Woking, UK
Your Mercedes
'71 350 SL, Mercedes 350 CLS SB, '94 Shogun 2.8 LWB, '73 Porsche 914
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Hi Malc, Thanks for the reply but for some reason the text has come out odd. Is that 13.8 or 14.8? Also mine has a separate regulator fixed to the body by the radiator about 2" x 3" x 4" in size. Should I be swapping out my alternator for a more modern one then with integrel regulator? I can't see this separate reg being cheap, if it's even available.
 

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