Y33 Alternator Replacement: What else should I do while I am at it?

[pnanda16]

97Q with 150KMiles, 'battery' and 'Brake' lights came on this morning and staying on. Idle voltage on battery shows 12V. Underload, it shows 11.5V). Considering the miles on the car, I believe the culprict is Alternator after reading numerous threads from before. Of course I will get the reman Alternator from Joe.Many posts (by Dennis and others) also mention that this might be a good time to replace the 2+yr old battery, idler pully, bearings etc. Can i please get a list of what are the recommended replacements? This is a Y33. All the belts were replaced 6months ago.

thanks a lotPhal

[maxnix]

Have you replaced the thermostat? There is always the intake and plenum cleaning.
Modified by maxnix at 10:27 AM 5/22/2007

[elwesso]

I would certainly inspect the tensioner pulley and see how it is. if the bearing needs done then this is the time to do it. Other than that, I dont think thats there much labor overlap. Battery wouldnt be a BAD idea as 2 years is probably nearing the end of its life cycle... but it might have another year or 2 left in it, but IMO its not worth the strain on the brand new alternator.

[Skibane]

On a 150K vehicle, if I was replacing the thermostat anyway, I'd seriously consider doing the water pump - and maybe even the fan clutch - at the same time.

And...once you've got the fan out, you'll probably be shocked at the number of cracks in it...

[bullittandy]

Isn't there a recall on 97 alternators? Maybe yours is original and the dealer will do it for free.

[pnanda16]

Thanks to all the inputs...

I wanted the fix rightaway, so even though Joe was cheaper by $120, had to do the dealer way. Bought the part from Dealer (after returning the core, it was $350+Tax ), drove to a mechanic 1mile away and replacement cost was $120. Car started right-away, the original battery hadn't discharged much (it was showing 12.4V when the car was off).

Replaced alternators. The 'battery' and Brakes lights went away. Idled for quite some time and then drove around around. Then under load, the battery showed 13.8V. So I guess I am all good here. Belts were replaced less than 6months ago. Mechanic (& I) didn't see other issues (thermostat), or fans etc. Is this because california cars are blessed? Mild heat and mild winter that parts last a little longer? Who knows - for now, car is running good. In fact, I was getting an intermittent engine stumple during idling which seems to have vanished after the replacement (any connection?). Only more driving will prove that.

thanks everyonePhal, San Jose, CA1997.5 Q45, 149K miles

[Skibane]

I was getting an intermittent engine stumple during idling which seems to have vanished after the replacement (any connection?).

Yes - If the alternator isn't putting out enough current at idle to keep the battery voltage from sagging, the idle and low-speed drivability can suffer.

BTW, a battery reading of 12.4 volts isn't completely dead, but it ain't healthy, either. Sounds like you dodged a bullet by replacing the alternator when you did!

[maxnix]

Sounds like you dodged a bullet by replacing the alternator when you did!

Maybe not if the battery is weak, it will stress the alternator immediately.

Highlights the "preventative maintenance" concept vs. "drive it till it breaks and pay the dealer now" methodology. Former is usually cheaper and less down time.

[pnanda16]

I am the preventive type - have done all the flushes every 2yrs/30K religiously. Car runs great. So here is my question on the battery replacement:

What should be the ideal reading on the battery when:1. engine is off2. idle3. under full load (AC, Lights, Audio @ high volume, rear defroster...)

After replacing the alternator, I have done the #3, to be close to 13.6V. What are the ideal numbers for the above 3 scenarios?

If they are off from the ideal #s, I will replace the battery ASAP.

About the engine idle stumble issue: I had done tons of research, done all the MAF/intake cleaning and then had taken to dealership. Dealership really did a very thorough investigation (but somehow missed the alternator failing signs?) - even checked sensors, spark plugs etc. and couldn't find a fault for the intermittent stumble. They had said to wait until problem became more apparent and diagnose from there. In the meanwhile, they had advised to replace the coil-sets and see if that helps ($2K+ to see if that fixes). I had taken their former advice and waited. It waited for just 5-days and the alternator failed. Seems to have taken care of the stumble - at least so far I haven't seen it.

If I see that alternator has really fixed the stumble issue, I believe this will be a new learning for this group. I had read a lot about the stumble issue (and most often MAF had turned out to be the issue), but now we should also recommend to do a full test of the alternator!

By the way, on a summary on this car: in 10yrs and 150K miles later, only 2 parts have failed. 1. ABS Relay ($25 part) failed at 146K miles2. Alternator ($300ish part + $120 labor) failed at 149K miles

Has been a super reliable car I would say. "Touch Wood". And thanks to the amazing folks here in this forum advising how to take care of the delicate darling to get years of great service.

thanks a lotPhal

[Skibane]

1. engine is off

Although the battery voltage will be higher immediately after you shut the engine off, it shouldn't eventually settle to any thing less than 12.6 volts (edited for brain fart!).

Quote »2. idle[/quote]The voltage will be between 14.1 and 14.7 volts, depending on ambient temperature, battery state of charge, etc. In cold temperatures, the voltage is highest, and drops as the temperature increases.

Quote »3. under full load (AC, Lights, Audio @ high volume, rear defroster...)[/quote]This voltage depends on how many loads you have connected - pretty hard to put an actual number on it.

Rather than guessing about your battery's condition, you might consider having it load-tested. Auto Zone (and other places that sell batteries) will usually do it for free. Essentially, this involves placing an exact, heavy load on the battery while checking to see how well the battery voltage holds up. If the battery passes this test by a comfortable margin, it's probably still got some life left in it.

[pnanda16]

Great, thanks for the detailed readout.

At shut-off, it shows 12.8V.

At idle, it shows 13.8V though. I think this is where the battery is showing its weakness (or is it that the reman alternator is not performing at its peak level)?

I will visit Autozone and verify with them...