Alternator

[kingsonlim]

Have just noticed the headlight flickering a little while driving just now. The RPM is also flickering up and down. The volt meter show the alternator charging, but does move slightly between 13.8volt - 14.2 volt. Had cleaned the spade terminal with wire wool and replaced the spade connector. It only stabilized the Rev counter slightly and does not affect charging voltage as above nor the flickering of head light.

Shall I take out the alternator, soak it in a bucket of water to clean out the mud inside or is that a sign that the alternator is on its way to heaven?

[TwoSheds]

Tis many years since I stripped an alternator, but they certainly are not rocket science - strip it, clean it, check it and - if it looks ok, reassemble it. In all probability it will then be fine.. A couple of hours work and you may save yourself £70

[Zedman]

It could also be the voltage regulator, the alternator just pumps out ac current I would have expected the symptoms of a faulty alternator to be low charging to the battery and not eratic voltages ?, just a thought )

[kingsonlim]

How do I test the alternator checking if the 'voltage regulator' is on its way out?

[Zedman]

First thing i would do is diconnect the alternator and do a short ride and see if the problems go away, that way you have strong evidence its the alternator and i supect the voltage regulator is bolted to it.

Secondly i would phone some auto electricians as this is what they do for a living and casualy get some free advise over the phone.

Thirdly try and borrow an alternater off someone to see if this is the issue.

[TwoSheds]

First thing i would do is diconnect the alternator and do a short ride and see if the problems go away

I don't like the sound of this... I don't know why, but the thought of spinning up an alternator without it connected to a load makes me uneasy.

Have you eliminated general earthing and wiring problems yet? If my headlights were flickering I would suspect wiring before more expensive things...

You say your voltage is 13.8-14.2... So it IS charging then...

[kingsonlim]

Have you eliminated general earthing and wiring problems yet? If my headlights were flickering I would suspect wiring before more expensive things...

You say your voltage is 13.8-14.2... So it IS charging then...

Additional Earth had been added from engine block to battery -ve. Alternator IS charging, but current not stable hence the flickering of headlights. Alternator is coming out this afternoon, rain or shine, for a good clean up.

[Jabba]

I can't remember how you check the voltage regulator but have you checked the voltage when the engine is spinning well (not just at tickover)?

Flickering sounds to me like the electronics that convert from the AC produced to DC isn't working right. It's normally part of the regulator I think and should smooth the current out.

[dave willard]

Have you eliminated general earthing and wiring problems yet? If my headlights were flickering I would suspect wiring before more expensive things...

You say your voltage is 13.8-14.2... So it IS charging then...

Additional Earth had been added from engine block to battery -ve. Alternator IS charging, but current not stable hence the flickering of headlights. Alternator is coming out this afternoon, rain or shine, for a good clean up.

I have a spare alternator if you want to try it to prove it as I suspect your alternator has been damoged by off roading
Bear in mind that you may have to change the alternator pulley as two sizes used if you get a second hand/ another one & use the wrong one all will work ok but rev counter will be wrong & tension pulley not in correct position

I also have a good alternator that has a cracked case(dont ask) free if anyone wants it for spares only

dave

[kingsonlim]

All sorted now....

Before:
- idling....15.32v - 15.55v (flickering...not good)
- 2500 rpm.....15.48v - 15.62v (voltage too high)
- voltage drop test....0.08v - 0.14v (okay)

After:
- idling.....14.96v steady
- 2500 rpm......15.22v steady

Basically took alternator out, rinse through water numerous times, got rid of quite a bit of grit in there , blow dry (with wife's hair drier ), re-fit. Swapped the spade connector to a ring connector....job done!!!

[Matthews]

Dave , I'll have your alternator as I have a brand new one with the main terminal stud snapped off so hopefully out of the 2 I could make one good one.
Cheers
MAtthew

[tecnick]

Are you collecting alternators?

Cheers Nick

[davew]

If he is there are four in my skip he can have if he wants to come skip diving

[Matthews]

Yes , I'm trying to sort out a replacement spare for mine so I can give my current spare (your spare) back to it's owner(you Mr Adams).

[kingsonlim]

just seen this:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

230amp...is that any good? Am thinking of fitting this into the disco and keep the current one as spare.

Any down side to a high output one? OR, do they really exist??