Alternator condition - How to check?

[scot850]

I pulled an alternator from a 2004 C70 that was in the junkyard after being rear-ended. So applying some limited logic, as the accident was at the rear, there was a fair chance the alternator was running at the time of the accident so should be a good stand-by from my 2000 R.

Well first the confusion. I don't know what alternator actually is correct for my car, as even the Volvo dealer websites conflict. Some say it fits and some say no.

Anyway, as it only cost $35 CDN, I thought it may be worth keeping as a back-up for my car or someone else's in the future even if it turns out not to be correct for my car. I replaced the alternator at the end of 2012 with a re-built Bosch unit direct from Bosch Canada. I have found the receipt and it is a Bosch AL-0805-X. Interesting as the Voltage regulator on the original alternator to the car was Bosch part #:

BR14-M1 and F OOM 145 230. The replacement regulator is also a BR14-M1 but the other number is F OOM A45 207

This alternator has the regulator part # F OOM 145 230 as seen here:

Regulator part number

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Going by the regulator can I assume it is the correct alternator? The part numbers on this alternator are:

Alternator part number

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I can't find a cross reference for the alternator and the only part site I can usually rely on for part numbers for my car is IPD as they are the only site that lists the correct 2.4 liter engine (B5244T2) for my car, everyone else lists a 2.3 liter engine. However the part number on this alternator is Volvo # 9459077 which is not listed a an alternate for my car but the Bosch # AL0805-X is.

A local parts supplier I use occasionally said they could test it off the car which they have done for me before with other alternators. However, they said there are 2 different alternators in 2004 for the C70 depending on if the car had a 2.4 or 2.3 liter engine. Naturally this must be from a 2.3 as they did not have the connector cables for the alternator but then suggested taking it to a starter/alternator shop and gave me a name. I took it there today, but I am always suspicious when they take the unit to a back room where you can't see what is happening and then come back and say the unit is bad and needs a total re-build at a cost of $250 CDN including a new clutch. They said the stator was badly grooved and would need replaced.

Call me cynical, but I decided against a re-build and will remove the voltage regulator and have a look internally for wear. I have found another parts shop I plan to take it to tomorrow assuming they have the correct connector.

The bearings are quiet so I had been thinking of buying a Bosch voltage regulator and cleaning it up and sticking it on the shelf, or would I be better keeping the regulator and only fitting if it is needed in the future?

If it is bad I can return it for a credit at the junkyard withing 30 days.

UPDATE: If I use the Vin # for my car in the Volvo dealer sites, they give the alternator as # 9459077. So I guess this is correct as they also list the engine as a 2.4 liter turbo.

Thoughts please!

Neil.

[abscate]

The 2004 C70 is a P80 chassis so it should work with your P80 as well

[scot850]

It was the auto parts store that made me doubt all this and that there were 2 different engines/options, but all the various websites seem to be conflicted. Because my car is the bastard of the bastards with lots of one year/model parts it can be sometimes difficult to pin the correct parts down.

Appreciate the input.

Neil.

[scot850]

Well all for nothing! Seems finding someone else to test an alternator in Calgary is becoming a very hard thing to do, especially for P80 alternators. No one seems to know how to test them or have the correct cables for their machines.

After 3 attepts today I finally found a parts place who said they could test it. After a lot of faffing around they macgiver'd a connector and then said the unit was totally pooched! They said the main windings were bad so the machine could not test it.

https://www.picknpull.com/check-invento ... D24J050182

From the arrival picture for the junkyard, the front is undamaged, it is only the rear panel that was pushed in. Hard to believe the alternator was the cause of the car's demise, so how can the alternator be so badly failed? Have to believe the guy testing it yesterday did something to the unit when testing or inspecting it. Either way I will return it to the junkyard and look for another.

Neil.

[454cid]

I would start looking on youtube for testing Bosch alternators of this generation/design. Alternators are all going to be similar.

[wizechatmgr]

All else fails, swap it out and see if it works. Takes about an hour if all is going well. 45 minutes of that is playing "Alternator Tetris."

[scot850]

If it was an NA motor and not a turbo (mind you not sure if it is much worse) then I would have a go at swapping it out. But I now think that the guy yesterday may have damaged it either in error or on purpose to get me to re-build it. At that point I would rather buy a Bosch re-built unit with warranty for a little more.

I will return it and and wait for another to hopefully turn up. The 'R' unit has only done about 15,000km in 10 years so hopefully it will be good for many more. Also, the car is on winter sleepover until spring (any way from April to May) and is on lay-up insurance until then.

Thanks for support and advice.

Neil.

[crlande]

misha from Serbia can help guide you thru testing. He did right for me!

[scot850]

I have equipment for testing an alternator on a car, but other than electrical meters and a 0-30V power supply I don't have anything for testing an alternator.

I can get a Bosch rebuilt unit from Rock Auto for $240 CDN + shipping and a $95 core charge and with a 24 month warranty. But then as it is a heavy lump there will be a fair bit for returning that. A local re-build would be good but there are none locally with a good reputation or I would trust.

I just need to decide if I shall return this for the Approx $40 in store credit at the junkyard.

Neil.

[abscate]

Rebuild at my awesome electric shop,is $100-150 and is much better than the Rock Auto crap.