Alternatori

[richard mackay]

Decided to see if my zetec blacktop would would turn over for the first time.

After a few turn and fiddling about i noticed the alternator was quite hot

which made me think what have i done.Its a new ATR seal alternator.

Cheers

Richard

[sj-bradley]

Sounds like a short circuit somewhere overworking the alternator or possibly the internal regulator is toast. Or possibly bearings shot.

 

Are the large wires also getting warmer than you'd expect?

 

What is the out put voltage doing?

 

Simon.

Edited March 1, 2015 by Simon B

[knights_templar]

the small alternator used on the Zetec does have an ignition feed for the internal electronics.

 

If the ignition was left ON whilst you fiddled, it may get warm, but hot?

 

if you did not start the engine, the alternator will not produce any charge, or turn fast enough for a mechanical fault to be apparent, so must be electronics, which do produce heat, but to what degree is debatable.

[sj-bradley]

An alternator needs a starting voltage and current to produce the initial magnetic field for the rotor windings. Once it is running, it can use the output it generates to feed back into these windings to keep the magnetic field present.

 

If it is not running, the internal fan will not be providing the necessary cooling air flow, so it will warm up and, yes, possibly get quite hot.

 

If you need to have the ignition circuits on for any length of time without the engine running, you might consider unplugging the small feed wires to the alternator to stop this effect. It would also take much less current drain from your battery during your testing.

 

I would also stick a post-it note on your windscreen to remind you that it's disconnected.

 

Simon.

[richard mackay]

Could i have the two small wires on wrong way round do you think.The battery drained

very quickly

Richard

[sj-bradley]

Post up your wiring diagram and we will take a look. Pictures would help too.

 

Thanks,

Simon.

[Longboarder]

Could i have the two small wires on wrong way round do you think.The battery drained

very quickly

Shouldn't make much difference. Both the small wires should be 12V positives, one from ignition live and one ignition live through the ignition dash light. Getting them the wrong way round just fails to extinguish the ignition light when the alternator is running. Duff alternator I think.

 

Nigel

[richard mackay]

When the ignition is on it should only be the big wire that's connected on this alternator with

a ring connector and nut that is live and the two small wires (ignition wire & dash light)are live

only when the engine is running.Well i seem to have the small ignition wire live with the ignition

switched on and not running.I wonder if that's why the alternator got hot.I'm probably not explaining

this very well but what do you all think now.

 

Richard.

[Longboarder]

Disregard my last posting. I'm uncertain as to what alternator you have. Can you supply a picture of the connections. Pinch one off the internet if you can't take one yourself.

The bolt on big wire is direct to the battery positive so is live all the time. Other small wires will only be live with the ignition switched on, engine running or not.

The diagrams below show some fairly common configurations.

 

Nigel

[richard mackay]

The Name of the alternator i have is an ATR seal Supplied by GBS. its the type 1 connections

according to your diagram Nigel plus the big wire which is not showen

 

Richard

[Longboarder]

OK. Reinstate all my information.

The B post is wired direct to the battery positive, maybe via the positive post on the starter solenoid(if that is convenient for the wiring.)

The L terminal gets a positive supply via the dash ignition light and is live as long as the ignition is on.

The IG terminal gets a positive supply from any ignition live source and is live as long as the ignition is on.

Check this is how it is wired.

Don't discard the alternator till you have the car running and can check its output.

 

Nigel

Edited March 8, 2015 by Longboarder

[knights_templar]

would agree with longboarder

[richard mackay]

Thanks for your help gents. i won't get back to the car till the week end as i work away

from home but i'll let you know how things go

 

cheers

Richard