Suspect Alternator

[philjw]

Hi All,

I'm having some charging issues. Measuring the charge voltage first thing in the morning my Uni-T UT203 shows a current of around 30 Amps from an Iskra 11.203.918 alternator rated at 80A fitted on a Lombardini LDW1404 engine. The alternator has done about 2 years service.  This is going into a battery bank which was originally 4 X 115 Ah batteries about 5 years ago.   The alternator achieves 14 + volts.  The rev counter has also stopped working.  What do you all think?  I have tested the alternator using the diode setting on the UT 203 and I get readings of 0.885 with the red lead on the alternator casing and no reading when reversed.

What other tests should I be doing?

I would have thought that the battery bank is sufficiently discharged to call for more than 30A first thing.  I don't have any fixed battery monitoring kit.  I do have the voltage reading from the Victron app from the solar panel controller which with no load this morning in the dark showed about 12.3V so around 60% charged.

I'm looking at replacing the batteries before long and I'd like to be sure that I can keep them properly charged.

 

Thanks,

 

Phil

[Tony Brooks]

I suspect a diode on one or two phases has failed, so the   output is low, and the rev counter is not getting its half-wave rectified pulses.

 

Point of order. Voltage is measured in Volts, and current in Amps, but I think we know what you mean. I am a bit surprised you are getting 14V+ because a failed diode tends to reduce the voltage, so maybe the solar is doing better than you think, but not with a rested voltage of 12.3V. I suggest taking it off and getting it tested. Give us a rough location and hopefully a local member will point you to a suitable company for testing

[BEngo]

Wherever you are give Lancashire Rotating Electrical a call.  Their courier services is very good, their turnaround is quick,  and their prices are OK.  I have not seen any adverse feedback on here either.

 

There are various threads on here where Tracy d'Arth has posted their contact no.  I think you can also contact them by e-mail.

N

 

[philjw]

Point of order. Voltage is measured in Volts, and current in Amps,

 

Yes, I should have said current of course  .   

 

Your thoughts re diode(s) echo what I was afraid of. I believe that the top limit on the diode test is 800mV.

I'll be heading towards Birmingham in a couple of days from Stratford upon Avon and I think that a company called Rotating Electrics in Stetchford is within striking distance of the GU so I will try them first.  Has anyone any experience of them?

 

Thanks for the prompt replies.

 

Phil

[Tony Brooks]

Best check all the connections just in case one has fallen off. Had a Ford in once with an intermittent rev counter and it was just a loose female lucar on the phase tap terminal, but I suspect yours is a nut and stud job. Caused a bit of head scratching because the current  nd voltage looked OK and then while testing that terminal got joggled.

[Fender151]

1 hour ago, BEngo said:

Wherever you are give Lancashire Rotating Electrical a call.  Their courier services is very good, their turnaround is quick,  and their prices are OK.  I have not seen any adverse feedback on here either.

 

There are various threads on here where Tracy d'Arth has posted their contact no.  I think you can also contact them by e-mail.

N

 

Another thumbs up for Lancashire Rotating Electrical, they recently supplied me with a replacement alternator, 70amp, only used for charging engine starter battery. Great service in response to my question regarding connection posts on the alternator body, quick delivery, couldn't find a better price, £130 + £10 delivery from memory.