Alternator?

[clickman]

If anyone can help me with suggestions for this electrical problem, that would be much appreciated.

I hadn’t driven the car for a few weeks, but put the CTEK battery tender on it a few days ago, and it went green a day or so later. I drove to work (about 100 km) on Thursday, and at the end of the day before I started the car I put the top down, which went really slowly in retrospect. I stopped once for a few minutes on the way. When I got home I turned off the engine, then tried to restart a minute later. All I got was a few clicks and weird lights in the dash. Jumper cables easily started the car. After driving it about another 10 km and shutting it off, I tried starting it again right away; no go, with same low battery symptoms.

Battery last replaced April 2011. Ignition switch replaced last summer (had trouble getting the key out). I've been having some issues with the central locking for some months now – sometimes I get the proper lock and alarm activation (2 flashes) and sometimes I get only one flash and the beep. I also just noticed that the spoiler wasn't all the way down, but manually lowering it worked.

The voltage across the battery when it was flat was 11.65. I tried the battery open-circuit voltage test from the Bentley manual and got 11.51 after leaving the lights on for about a minutes. Then I charged the battery again with the CTEK until green light, and did the test again. 13.15V dropped to 12.82.

I started the car ok, ran it for about a minute, shut it off and measured 12.90. Leaving it and coming back the next day I measured 12.93.

Today while running the engine I measured about 14V initially, but this steadily dropped until I shut the engine off at 12.5V. The voltage drop was slowed by revving higher.

I store the car for the winter, but use the CTEK maintainer.

Battery? Alternator? Voltage regulator?? Any suggestions welcome. Thanks.

[Steve Tinker]

First off, check to see what drain you have when the car is stationary with everything switched off.
Do this by disconnecting the neg side of the battery and connecting your multimeter between the gound wire and the battery terminal. Put multimeter selector to mA and take reading - with everyhing off (including interior lights) you should see +/- 30mA. Anything much more and you have a parasitic drain which is slowly flattening your battery.

A fully charged battery should read 12.6v after charging and then applying a load (headlights) for about a minute as you have already done. 12.3v has the battery @ about 50% charged.

Alternator charge rate usually starts off +/- 14v, dropping to 13.6v after a few minutes running with a fully charged battery. Anything lower than 13.2v could be a faulty alternator / regulator.

[clickman]

Thanks, Steve. The voltage appears constant over time when not running the car, so I don't see how the parasitic drain could be applicable.

On the other hand the dropping voltage while running sounds like the alternator or voltage regulator. Any way to confirm which?

I'm taking the battery in to have a load test on Friday just to rule that out.

[Steve Tinker]

1) Parasitic drain is in mA not v - it is a continuous drain on the battery & over several days will flatten the battery.But by what you said it may be OK, but it costs nothing to check...

2) You need a specialised tester to determine if the alternator vs regulator is at fault - I can't help you with this.

3) Load testing the battery is a good idea - even if its only 30 months old and maybe still under warranty.

[clickman]

The battery load tested Good, so it's the alternator or voltage regulator. I'm trying to get the alternator out and am stuck.

Looking at Bentley and 101 Projects, both talk about "tapping" the idler pulley bolt such that the back bushing gets loose, allowing the alternator to be removed.

I've been doing a lot of tapping (some I'd have to call quite a bit harder than that) and wiggling. The alternator moves around a little, but won't come out.

The back bushing seems locked in the alternator flange and appears to require an awful lot of force to break loose from that flange. Look at the attached pic - that bushing is in there solid.

Is breaking loose of the bushing in the flange really required? What exactly is holding the alternator in on the idler pulley side? Is it squeezing of the support slot by the flange in the back and the pulley in the front? Now that things seem loose, can I just take a pry bar and lever up the idler pulley side (as one other forum member has done)?



To make more access, Bentley also talks about removing the U-shaped protective shield above the idler pulley. Of course it doesn't say how, and the bolt holding it down is impossible to get a wrench on without taking off the shifter cables. Anyone get it off?

[JFP in PA]

Originally Posted by clickman

Is breaking loose of the bushing in the flange really required? What exactly is holding the alternator in on the idler pulley side? Is it squeezing of the support slot by the flange in the back and the pulley in the front? Now that things seem loose, can I just take a pry bar and lever up the idler pulley side (as one other forum member has done)?

Yes, giving the mounting bolt a solid smack is required as when tightened, it pulls forward and traps the mount. Once moved sufficiently by a couple of whacks, the alternator should pop right out.

[clickman]

I give up. I don't see any alternative now but to take off the intake to make some room to work (and to retrieve a lost bolt).

After shooting some PB Blaster on the bushing, I finally managed to knock it back about 1/8", and the alternator seems loose, but there's just no room between the idler pulley and the U-shaped shield above to rotate the idler pulley bolt up and out of its cradle.

I thought there was only one bolt holding on the shield (which Bentley blithely says to remove, without any instructions). I managed to finagle an offset socket through the cables and hoses onto it from the engine compartment, but once I had it out I managed to knock it back into some inaccessible crevice, even with my magnetic retriever. I then discovered that there's a 2nd bolt I can't seem to get a wrench on at all. Grrrr.

I sure wish I could have watched one of you successful folk actually perform this major PITA.

Damn good thing this isn't my daily driver.

[Steve Tinker]

Clicky....
Don't give up yet. My alternator was also difficult to remove, in the end I found that removing the outside 10mm bolt holding the black intake manifold gave me an extra bit of space to rotate the alternator. The bolt is easily seen and only takes a minute to remove.
Also the bushing (once loose) should go back a little further than 1/8". Loosen the bolt out a bit more and give it another tap with a hammer after hitting it again with PB Blaster.
I didn't remove the shield either....

[pjq]

Clickman maybe this angle will shed some light.

[clickman]

OK, I admit it, I take instructions too literally, instead of applying a liberal dose of common sense.

I just backed out the idler pulley bolt the rest of the way and removed the pulley. The alternator then had oodles of room to come out. I had been following the Bentley and 101 Projects too closely, neither of which say to do this. And I read or saw on a video where one guy had tried backing out the pulley bolt and it wouldn't separate from the bushing.

Anyways, the alternator is out now, was tested, and the VR is being replaced. Interestingly, the decoupling pulley wasn't working either so it's also being replaced.