Fitted wrong AMP altenator

[CrankmasterII]

Hi
I recently fitted a replacement altenator which was rated the wrong AMP
Origional one was 120A and fitted with a 115A
Has lasted me 6 weeks and packed in last night
I am going to rebuild my origional one and refit it the weekend but I need to get the car for MOT tomorrow eve for test
Does anyone know what would be the cause of the failure?
Brushes or Regulator? I wil test the regulator this evening anyhow
My thinking been that the brushes are cheap and can fit them in situ just to get the car running for tomorrow evening, rather than paying out for a regulator for the one on car at moment and still having to change it back to origional rebuilt unit the weekend
Many thanks in advance.

[SD1too]

I recently fitted a replacement altenator which was rated the wrong AMP
Origional one was 120A and fitted with a 115A
115 amps maximum output is absolutely fine Willie. It's not "wrong".
I am going to rebuild my original ... Does anyone know what would be the cause of the failure?
What were the symptoms? Mechanical noise, or constantly illuminated warning lamp or charging voltage excessive?

Unless you've been very unlucky, it's rather odd that two alternators should fail within 6 weeks. Has anyone been running the engine with the alternator disconnected? Is the battery OK; perhaps it's drawing excessive current?

Simon

[CrankmasterII]

Hi simon
Battery light just came on while driving home last night
Got 12.5 volts ignition off and 12.1 whith engine running
I've ordered new brushing a which I'll put in and should be ok and check the reg later.
Few variables into the equation at the moment
1. While changing alternator the last time I busted the hydro mount
I just used skis fast glue and stuck it back that way, small increase in vibration
2. Last week while towing caravan power went right down, been up and down since and UBP had started acting up needing a few taps sometimes to get it started
(This may also be to alt on the way out?)
3. Found my plenum a with about 3 inches of water which I reckon filled up during the week I was on hols as it pelted down for 5 days and had car parked up under a tree.

So all in all a few gremlins there
Going to fix alt and have a new pump on order and see if everything works out

[Snagger]

If you still have problems with your alternator after your refurb


http://www.the75andztclub.co.uk/forum/showpost.php?p=2138341&postcount=7


Snagger.

[DMGRS]

115A should be plenty. First thing to try to 'revive' a failed alternator is a brush and regulator pack. :)

[CrankmasterII]

Well just fitted new UBP and fired up no problems
Took the regulator off alternator and brushes were well worn
Slip ring was fine just had to give one if them a rub of sandpaper to clean up the dirt on it
Awaiting new brushes tomorrow all ready to fit
Was talking to an alternator specialist today and he told me to check continuity between the two slip rings, he said it's a test to see if the rotor has failed
Also said the 115A never give trouble on the rotor and only the very rare one on the 120A
Handy to check it anyway once you have the slip rings exposed
Will report back on the assembly tomorrow

[munroman]

Well just fitted new UBP and fired up no problems
Took the regulator off alternator and brushes were well worn
Slip ring was fine just had to give one if them a rub of sandpaper to clean up the dirt on it
Awaiting new brushes tomorrow all ready to fit
Was talking to an alternator specialist today and he told me to check continuity between the two slip rings, he said it's a test to see if the rotor has failed
Also said the 115A never give trouble on the rotor and only the very rare one on the 120A
Handy to check it anyway once you have the slip rings exposed
Will report back on the assembly tomorrow

Always worth checking that the engine earth connections are in good order too!

[CrankmasterII]

Well was let down by the post office for delivery of my brushes
I ended up drilling out the old brushes and soldering some wire onto them and re attaching them to the regulator for a temporary fix and also to see if that would cure the problem
Worked a treat.
Went to NCT (Irish equiv to MOT)
Failed on front right shock, anti slip cover on clutch pedal, handbrake effort,headlight bulb out of focus and a tyre.