Starting issues! / give me a lesson in using a multimeter?

Well I have some starting issues.

Top put in context, the vehicle is a 200tdi.
Its had a new starter motor which is in good health.
Its just had a new alternator - as my alternator was dead, the replaced with one from a mate which was also dead, and then replaced with a new one.

The three questions i most want answering are:

Can anyone confirm my alternator wiring is correct, the original had the lucas plug, and it was replaced with one with posts, I put the two thick wires on the on the main output post and the thin brown and stripe or whatever it is on the D+ post.

How do i test for a parasitic drain?

How do i test my battery to see if its that that's knackered?

My gut tells me its the battery, the dead battery light is coming on every time i start up so somethings not right struggled to start yesterday and i jumped it off another battery i had with me. Ran for 20 minutes flat out back home, when i set off i put an el cheapo meter in the fag lighter and on tick over it said the battery was dead but the alternator output was fine - touched my accelerator and the battery was reading charged - I need to test it with the multimeter which i have but I'm not clued up enough to know what I'm testing or what I'm looking for.

My only other "suspect" is that ive recently replaced 3 out of 4 glow plugs ( fourth one seemed unwilling so its stopping there until i grow some balls ) Could it be possible that the glow plug relay is stuck on an that's draining the battery? How would i test that? only reason it comes to mind is my no/1 glow plug was absolutely cooked and since they are wired in series wouldn't that stop all the others working? So now Ive replaced them i might be left with glow plugs draining the battery. - I'm just trying to think logically based on things that Ive changed recently!

Quite capable of putting the multi meter on 20V setting and prodding things but beyond that i don't really know what im doing so if i need to test the battery what settings should i have it on and what numbers should i be looking for -

Will report my findings!

YouTube is your friend.
There are thousands of multimeter tutorials uploaded. Informative ones too.

what year what type of alternator fitted ,has it the correct pulley and is the belt tension OK have you checked for good earth on engine and chassis,you should never try charging flat battery via the alternator ,connection are right .have you connected the starter motor correctly battery feed and alternator feed on same terminal
If you measure the voltage (20 volts DC scale ) with the battery disconnected flat battery should read around 11.18 volts any reading below would indicate faulty battery ,charge the battery fully and measure voltage
should read around 13.6-13.8 volts ,refit and start when running measure voltage on battery terminals the reading should rise to 14.7 volts when rev's
increased to confirm the alternator is charging would not worry about parasitic drain till you have confirmed the battery and alternator are OK

As above - you can look up the state of charge curve for you’re specific battery but > 12.85 indicates 100% SOC for most batteries. Less than 70/80% SOC normally means new battery time.

Check alternator as above >14.2 at tick over rising with revs normally indicates a functioning alternator.

To look for parasitic drain. Pull each fuse in turn and measure the drain across the empty fuse terminals.

You can check for parasitic drain using the amps reading on the meter. With everything turned off, disconnect the positive terminal and connect the meter between the terminal and the positive lead. Any current flowing to the battery will have to go through the meter. If there is some current flowing, remove fuses until it stops to identify which circuit is faulty. DO NOT attempt to start the vehicle with the meter in the circuit, you will likely start a nice fire.

When parked up, disconnect the earth from the battery, this stops all drains and will tell you if battery is dying on it's own. Next day it will show if still full of life or down a bit.

By dead battery light I guess you mean the ignition charge light ? With a land rover 200 the tick over speed tends to be to low for the light to go out at start up. A touch on the throttle and it goes out.

Just becareful with your multi meter when measuring current it’s very easy to fry the thing, make sure when you measure the ignition is off and the keys out, doors shut, no lights on both internal and external no radio one, everything you can think off.

Checked everything problems were many as usual.

Alternator alignment was poor and pulley wheel damaged so was shredding belts so constantly running slack so charge output was poor or inconsistent. Fixed that.

Battery was draining constantly slowly, not from issues with vehicle wiring just a dud battery (annoying!) My "known good" battery leaked acid everywhere New battery fitted supplied by Tayna who were brilliant. Got a monster of a battery in now ( had to weld in a bigger tray ) and it starts on the button. Happy days

90deftdi said:

New battery fitted supplied by Tayna who were brilliant.

Click to expand...

Read this as, "New battery installed by Tanya..." and thought to myself..."Could I have her number, please...?"