Strange noise with battery load

[jindle]

Been doing minor fixes and washing her all day to finally get the cover on, but noticed a strange a strange intermittent wailing noise when I turn both the full beam and lower fogs on.

I know the car has various wiring issues so doesn't behave well if there's too much load on the battery, but anyone come across that noise before?

[Yatesy350i]

Bit of a guess. Does the car have an alarm? Could be something to do with the battery voltage dropping away and triggering something in the alarm?

Other than that no idea.

I'm seriously depressed with wiring at the minute. So much in fact the Stella has be opened a little early today.

Karl.

[mrzigazaga]

I get a weird high pitch robotic type noise for a few seconds coming from the ECU area when i turn the steering wheel a little bit..I hear the pod motors operating but not a whaling noise though..Ziga

[adam quantrill]

It could be the belt, new ones are just over 6 quid. Or put a couple of drops of neat washing up liquid on it.

[mrzigazaga]

Mines definitely an electrical whine...Like when you gently press a cordless drill trigger without it moving..Bbbzzzzzsssssbbb...

[superwedge]

its just the load from everything going ,i get it as well,i got big mother ducker battery on my 680 amps, you have to have the right one on thses;s cars,

[jindle]

Zig my other car makes that same noise, something to do with the PAS.

Super any idea where the noise is coming from though?

[superwedge]

its just the pump with under load,

[V8 Fettler]

Those didode things make weird noises when passing high current.

[superwedge]

a big battery does help.

[jindle]

Either that or the goat tied to my bed...

Any battery recommendations? Some sort of Bosch unit presumably?

[V8 Fettler]

jindle said:

Either that or the goat tied to my bed...

Any battery recommendations? Some sort of Bosch unit presumably?

The biggest (amp-hour) you can fit, use a local supplier so you can take it back if it goes wrong.

[superwedge]

my one is 670 amps , size is 250mm long /170mm wide, and 170 mm high,fits tight as a duck ass thou,

[RCK974X]

The common sense, boring, question........

Are you sure the fanbelt isn't slipping ???

They can do that under load as well as when revving the engine.....

[carob]

Used to know a mate;) Who Knew a lass that made a strange noise when the batteries where under load also.

Rob

[Skyedriver]

V8 Fettler said:

Those didode things make weird noises when passing high current.

I also make a strange noise when passing... oh sorry meant to post this in "Health Matters"

[jindle]

Why would the fan belt slip under heavy load?

[wooly350i]

Hmmm, it could slip under heavy mechanical load ie ; power steering or putting ya foot down but I don't about slipping under electrical load.
Just my sixpence worth.

[Wedg1e]

jindle said:

Why would the fan belt slip under heavy load?

Because the load on the alternator causes it to be slowed down (electromagnetic drag, if you will) while the crank pulley is still trying to drag the belt around the alternator pulley.
That's why you often get belt squeal for a few seconds immediately after starting the engine: the battery has had a severe depletion by the cranking effort and the alternator is trying to replenish the lost charge, thus it gets slowed by the magnetic field being created in the windings.

[RCK974X]

Agree - An alternator is an electric motor in reverse (that's a simple way to think of it), so the more current you demand from it (headlights, flat battery, etc) the more power it takes to turn the pulley.

So if putting the headlights on makes it squeal or whistle, it is possible the belt is slipping slightly, and a lot of owners don't realise that.

If the belt is old and shiny on the 'V' then it's even more likely.

Wooly - the way to respond to your statement is "where do you reckon the electrical energy (= power) comes from then ?" - It can't appear by magic, so must demand energy in from somewhere else to generate the electricity (i.e. the engine via the fan belt).

Edited by RCK974X on Sunday 29th December 08:28