Battery drain, help please!

[AlBundy]

Hi everyone, I have a 1986 1.6 Diesel that has a battery drain issue.

I have checked for parasitic draw and with the alternator disconnected I get 0.04. With the alternator connected i get 0.74. I cant post pictures unfortunately, says my region is blocked? I am in the UK.

Does this sound right, can an issue with the alternator cause this problem? I tested the other cables coming from the battery (battery tender cable, upgraded lights, and connection to Sargent EC155 and they don't seem to cause the same problem.

Due to go away in the van tomorrow with the family for 8 days, so its all a little last minute and I really don't want to cancel!

Thank you in advance.
Al

[Lillythefrenchie2026]

Long shot, but does your head unit have a contact live feed to it. I had this issue on mine when I fitted a new stereo.

[R0B]

If you type battery drain in the search box, there will be a few pointers there.

[AlBundy]

Thank you both, I had had a look through, and was mainly wondering whether it's worth working through all of the rest of the tests if my theory about the alternator is right, if it helps I can explain what I have done so far.

I removed all 'additional' cables that run either to or from the vehicle battery, and tested the drain by linking a multimeter between the -ive terminal on the battery and the -ive battery terminal cable, adding the cable connections one by one, and testing again. 

+ive attached to: Fuze box, lights, sargent ec155, battery tender
-ive wire attached to: engine block, battery tender

ampage when set to test 10amp, was 0.04.

+ive attached to: Fuze box, lights, sargent ec155, battery tender, and alternator
-ive wire attached to: engine block, battery tender

ampage when set to test 10amp was 0.55.

This to me suggests that testing the fuse board, upgraded lighting and Sargent system wouldn't result in finding anything as there wasn't significant draw from those systems (unless 0.04 is significant enough to completely flatten a battery in 5 days)

If this logic holds up, and there is a potential / probably fault with the alternator, then I can hopefully (if the wind blows in my direction) get a new one, fix that 'quickly', and my holiday is back on  

If this logic doesn't hold up, then I will likely need to send the van in to be fixed, and the holiday is off

E D I T: I also found that with the alternator attached to the battery the battery tender (that had been attached the whole week) wasn't getting the vehicle battery to go above 6.3v, when I removed the alternator cable and reattached the tender it had quickly gone up to 7.4v (and rising).