This morning the voltage across terminals was 11.94V. I started the engine and voltage was 14.3V and after few seconds dropped to 13.96V. After 10 minutes it showed 12.61V. Bonnet (Hood) open all the time.

With the engine running current drain was 14 to 15.07Amps, dropped to 4.19A after few minutes. With engine stopped after 30 minutes current is constant 0.15A Bonnet still open.
The new battery sticker says "Keep above 12.01V (50% discharged) and Warrantee (4 years) VOID 10.6V (100% discharged)"
What deductions can be made from these readings? Is 0.15A drainage still high?
Are you saying the voltage dropped to 12.61 with the engine running? If so the alternator is toast and may be the cause of the battery drain.
0.15A after 30 minutes is too high. Pull fuses one at a time to help identify where the drain is coming from.
 
Have you still got the old battery? No way a new battery should drop that low with engine running unless it is duff.

Sounds like diode in the alternator might be letting current go the wrong way.
 
Before fitting, the battery should have been fully charged as it may have been sitting on the shelf for some time and been in a low state of charge. With a small 4 amp charger it might need 24 hours or more to reach a full charge.
I have MF31-1000's in both my P38's and similar Hancook batteries in my transit and other cars, never had a problem with them.

1. What charger will do the job?
2. The P38 alternator voltage is set at 12.2V but this battery needs 14.7V. How can the setpoint be set to 14.7V?
3. I read a new voltage regulator need to be fitted. I googled but cannot find any regulator.
Help
 
Ty
1. What charger will do the job?
2. The P38 alternator voltage is set at 12.2V but this battery needs 14.7V. How can the setpoint be set to 14.7V?
3. I read a new voltage regulator need to be fitted. I googled but cannot find any regulator.
Help
Type 14.7 voltage regulator into the search box top right of page there's loads of posts.
 
1. What charger will do the job?
2. The P38 alternator voltage is set at 12.2V but this battery needs 14.7V. How can the setpoint be set to 14.7V?
3. I read a new voltage regulator need to be fitted. I googled but cannot find any regulator.
Help
No P38 regulator has ever had a 12.2 volt set point so I suspect your regulator is duff
Linky no worky:)
 
1. What charger will do the job?
2. The P38 alternator voltage is set at 12.2V but this battery needs 14.7V. How can the setpoint be set to 14.7V?
3. I read a new voltage regulator need to be fitted. I googled but cannot find any regulator.
Help
A 4 amp smart charger will do the job but may take more than 24 hours,
A link to the correct regulator was posted a couple of days ago, the regulator is from Mobiltron
Mobiletron VR-VW010 alternator regulator.
 
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Are you saying the voltage dropped to 12.61 with the engine running? If so the alternator is toast and may be the cause of the battery drain.
0.15A after 30 minutes is too high. Pull fuses one at a time to help identify where the drain is coming from.
I will have to start doing that. I believe you have mentioned somewhere that you have rigged up so you can monitor the drain with all doors closed. Could you give me an outline how you have done that. I would like to rig up and connect to a laptop and monitor for few hours.
 
I will have to start doing that. I believe you have mentioned somewhere that you have rigged up so you can monitor the drain with all doors closed. Could you give me an outline how you have done that. I would like to rig up and connect to a laptop and monitor for few hours.
i just use a clamp meter to detect current flows, never found a need to monitor over a period of more than the few minutes it takes for the BECM to go to sleep.
 

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