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Subject:Re: Alternator Troubleshooting
From:Roger Whittaker
Date:Sun, 30 Oct 2011 13:06:16 -0700

Dear light up your life

Been my experiance with a variety of vehicles that those symptoms lead
to a new alternator if the wires are all I'n place
Good luck
Regards

On Sunday, October 30, 2011, Jim Felder <jim.felder@gmail.com> wrote:
> I quickly realized
>
>> that the pulley�s were different between the alternator in the van and the
>> rebuilt one in the box, so no-go for a quick and easy swap since I don�t
>> have an air compressor strong enough to power an air-wrench to �bump� the
>> retaining nut on the pulleys. Tried holding it with a vice and such, but
>> really it�s on there tight.
>>
>
> You can hold the alternator body in a vice, gently and padded with
> cardboard, and hold the pulley with an oil filter strap wrench while you
> put a socket on the nut.
>
> Jim
>
>>
>> So, some quick testing with a voltmeter:
>>
>> Test 1: with the engine running, I put my positive lead on terminal B and
>> the negative lead on terminal D. The voltage was 7.1V. Battery light still
>> on dash.
>>
>>
>>
>> Thinking this is a bad voltage regulator or brushes, I pulled the voltage
>> regulator out. A little grimey at the metal contacts, but the brushes
>> looked fine. Cleaned the grime off and re-installed the regulator. Restart
>> the engine and check voltage across terminals B and D and I get 7.1V.
>> Battery light still on dash.
>>
>>
>>
>> Just for kicks, I pulled the regulator out again compared it against the
>> one in the new alternator from FLAPs and they look identical physically.
>>
>>
>>
>> Test 2: Installed the new voltage regulator into my old alternator. Started
>> the engine and tested across terminals B and D and I get 6.9V. A few other
>> measurements at this point (wish I had taken them in previous tests):
>>
>> Terminal B to alternator housing: 11.75v, dropping to 11.5v after about 30
>> seconds
>>
>> Terminal D to alternator housing: 4.57v
>>
>>
>>
>> So, given that information and testing, I�m thinking either I have a bad
>> alternator (diode, perhaps) or I�m chasing down the wrong path altogether.
>>
>>
>>
>> One other caveat to mention: on my original alternator, the suppression
>> condenser was not mounted the same as the new alternator from FLAPs (which
>> was connected to terminal W and the alternator housing). Mine has had the
>> connector cut off and mounted to Terminal D, and the condenser itself had
>> the hole enlarged and mounted to terminal B. Don�t know that this would
>> cause an issue, but thought I�d mention it. It�s been this way since I
>> acquired the van earlier this year.
>>
>>
>>
>> Any thoughts or advice on other things to check? Or, next steps to take? Do
>> I replace the alternator at this point (find a way to swap the pulleys or
>> get a replacement one with the correct pulley)?
>>
>>
>>
>> Thanks in advance!
>>
>> Gregg
>>
>>
>>
>> 91 Westy (Blueberry)
>>
>

-- 
roger w
 From Proverbs:
Under three things the earth trembles, under four it cannot bear up: a
servant who becomes king ...
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