Alternator or Battery?

Hi gys & gals,

just got back into the Land Rover loop with a 1975 Series III 88" Petrol.

She's pretty solid (for the little I paid for her) but I'm a bit concerned about something.

When I start her in the morning the turnover is pityful, as if the battery is dead, just about turns over once, but enough to start her up - just. Only the one morning I had to drop the battery on charge for an hour.

When I'm driving along at night the brightness of the lights dims until I rev the engine. And when sitting at a junction even the indicators slow down unless revved up.

I've been to a local garage and they tested the Battery and Alternator and said both were fine, although they didn't totally rule out a duff battery.

Idea's?

Only my budget is tight and I didn't want the expense of replacing the wrong thing.

Thanks in advance.

try a new fan belt first and do the tension correctly.

if money is tight, can you not borrow a battery off someone, say for a weekend to try out?

then you will know which is the problem component.

my gut instincts tell me its the alternator.
you may just require a regulator though and not a rebuilt unit.
someone on here local to you, might have a spare alt to try???

im new to landrovers myself but been mechanic for 15 years sounds like bad earth to me just kleen or even replace starting with the ones to the engine

Borrowing spares is probably not an option, but a good suggestion.

I'll check the earthing and fan belt tomorrow, cheers.

a bad earth is very common with any lecky fault, but in this case (lights dim etc..) its prob more likely the options in my previous post.

if you're sure you can trust the bloke that tested the batt and alt then bad earth sounds like the cause

When he tested it what did he use? A little meter with stupid little wires?

The only real way to test a battery is to put a meter which consits of a huge resitor and volt meter, I had a guy about a year back "check" my battery, he put a little meter on it with wires that wouldn't even carry an amp, his test said the battery was fine, was it hell!

discomania said:

When he tested it what did he use? A little meter with stupid little wires?

Click to expand...

Actually, yes it was

Had a check today and found one of the earthing wires was loose, so that wouldn't help! I've tightened that up, so I'll see how it goes.

I'm planning on wiring in a CD player, so if the battery is weak that'll probably finish it

i'd be wary of stickin a cd player into a series. as you know the ride int smooth and this will probably cause the cd's to skip. i put one in a sports car and the cd's jumped all over the place during hard driving so i assume the series will do the same but only during any driving.

you'd be better wiff a mp3 player

Found a bad earth from my battery, so I'm hoping for now that's all it was. Started a lot better this morning. So I'll just give it a couple of days see how it goes.

As for the CD player, well it's a pretty good anti-shock. I had it in my MGB, another bumpy ride, and didn't skip when driving over cobbles. If it does prove no good in the Landy then I will be going the MP3 route as you suggest

This isn't a Landy question, but I'm figuring the answers are going to be generic.
Can anyone remind me what the voltages are to test battery and alternator.
Is it 13.7v on standstill, then check for 14+volts with engine running?

Then is there something to look for with the voltage dropping when you switch the engine off?

The reason I ask is that my collegue hailed me down to help her start the car this evening, she says it never starts on a cold day. My first guess is the battery but she says she's had this checked out. I said I'd bring my meter to see if i can check it.

anything over 12.5 volts will charge a 12v battery but 13 to 16 is best over 16v will burn battery out under 13v charges it to slow check for voltage drop if present put bulb between negative terminal and negative lead if it lights its got a drain.check levels in battery even if these seem alright battery probly scrap i checked everything on my pajero even got them checked by batery specialist all seemed ok i changed the battery and problem was gone

yer 12 volt battery is actually 13.2volts as each cell is really 2.2volts.
anything less than 12v will have difficulty in turning yer motor over . and these quick boost charger will blow the ship oot yer battery if used too much. slow chargin is much betta fer yer battery

a battery looses 10% of its efficiency every for 1 degree temp drop, (below a certain figure which i cannot remember from day release some 40 yrs ago).

so anywhere near the present day/night temps will cause any battery not 100% fit, to give big problems. if youve got a diesel, so much the worse.

also batteries over 3 yrs old do start to go off.

put all 3 items together and you are almost certainly walking home.

Some of this explains my 2.25 diesel's HORRIBLE cold morning start syndrome.

I changed the starter & alternator, and upgraded the glow plugs and put a 650cranking amp battery on and she was fine through the summer. About October she started (or didn't!) again. It'd take a full minute on the plugs and even then she'd take a good long crank to start.

I dropped the oil, flushed the engine and replaced new oil and filters and she was much better for a short while. Now she's just as bad again. On very cold mornings I invariably have to use the heavy start charger. Once warm though, she's fine for the remainder of the day unless left a long time.

Are there any solutions to this problem? After reading the above posts I'm concerned I'm going to end up replacing the battery every 6 months and cleaning the glow plugs every week!

the solution is really to make sure the injun is in good condition and the battery is big enough for the job. also the battery must be 100% fit.

any weakness in the whole system will cause problems in the winter months.

you might try warming the injun first, by other means. or keeping the lump a bit warmer overnight.
under the sump heater perhaps?
a blanket?

i int check back thro the fred but have you checked all yer earths and other connections yet?