Alternator died

[Len1955]

My 100 amp alternator died after just 3800 ks.
Is a Bosch BXH1238A a good replacement.
Cheers
Len

[Innuendo]

What was the brand that died?
The Bosch should be fine although only a 70amp alternator.

[Len1955]

I do not know it was an ebay one that looked like an original alternator, Yes I know it's hard to believe an ebay product failed.
Would 70 amps be enough or are there reliable bigger one's at a reasonable price.
And I have just fitted aftermarket gauges with no alt warning light, does the alt need the warning light connected to work.

[maxsandman]

Yes, the alternator does need a warning light, the spade terminal on back of the alternator is called exciter, as it excites it to charge. You can have a bulb wired in line under the dash or under the bonnet if you don't want it in the dash, but without a bulb lighting up, the regulator won't act. A sparky could also prob put a resister in the wiring to do the same job, if you want to check that out.
70amp alternator is fine unless you have a lot of electronic gear, stereo, heap of lights etc in the back. Most of these cars originally had 35 or 40 amp alternator unless factory a/con, & then it was 55 amp

[Len1955]

Thanks Max I will try that, I did read on another forum that the bulb could only but 2 watts is that right
How can I test my alt with a multi meter to see if it is OK.
Cheers

[Len1955]

OK I just hooked up a T10 5 watt bulb and test ran, it's putting out 14 volts so alternator is working OK.
Would it be OK to use a 5 watt bulb permanently.

[maxsandman]

OK I just hooked up a T10 5 watt bulb and test ran, it's putting out 14 volts so alternator is working OK.
Would it be OK to use a 5 watt bulb permanently.

Im no expert, but i think that would be OK, just need to "load" the alternator up to tell it to charge.
Also, I have found when using LEDs as warning lights, sometime it's not enough load for the alternator to charge, in case you were thinking of going that way

[Len1955]

Thank's Max for the help, I have done some research and measured the resistance of the original dash bulbs and get about 13 ohms so for now I will get a resistor close to that and a diode and make up a lead to go under the bonnet, latter on I will fit an alternator led in the dash.
The 5 watt is about 3 ohms.
Cheers