alternator pulley Topic is solved

[oragex]

- My 2007 V70 with 104K runs fine, zero issues, but I am wondering...

- Does anyone know the lifespan of alternator decoupler pulley?

- How do you diagnose a bad alternator decoupler pulley?

Remove the belt (you may find it's tricky as I think it takes a special torx tool to release the tensioner) then rotate the pulley by hand to feel if it turns smooth without grabbing, then use a screw driver to inspect the clutch - check youtube videos. May also give the pulley a kick, it should keep turning 2-3 turns without stopping too quickly, should have some inertia. But it's the clutch that would go bad first. I think the alternator is tricky to remove from the turbo engine, maybe it has to come out by the headlight hole after removing the headlight .

But while there also inspect the tensioner and especially the A/C pulley bearing - turn it by hand and feel for roughness/dry noise. At 110K miles I would rather look into the tensioner and A/C pulley bearing, the alternator pulley should be good to go up to 120-130k miles at least.

[cn90]

- Serp belt Pulley is loose (free-wheeling), so I will replace it soon with INA. Will also replace the serp belt itself.

- The AC Pulley has only 104K and seems OK, I spun it and no significant noise.
What is your experience with AC Pulley bearing?

- FYI, my 1998 S70 GLT AC Pulley bearing was loose at 180K and I replaced it at 180K.

[vtl]

- My 2007 V70 with 104K runs fine, zero issues, but I am wondering...

- Does anyone know the lifespan of alternator decoupler pulley?

- How do you diagnose a bad alternator decoupler pulley?

Volvo alternator rule of thumb: 10 years since manufactured - rebuild yourself. Good quality bearings, voltage regulator, test diodes (or simply put new), contact rings, and, yes, pulley. Quality parts would cost you around $200-ish, but the result is a better alternator than anyone around rebuilds, or even Volvo puts in new cars now.

It is important to get the right class of bearings (low friction seal, high temp, if I remember correctly), otherwise even good ones will die soon. They are not cheap and you have to sources them from overseas, but my rebuilt alternator is silent.

[oragex]

This was my pulley at 120k miles. Still working but could definitely hear it when span (?) by hand. Noticed quite common when working at the junk yards. But if it feels smooth with no 'dry' noise, I'd leave it there, maybe it was already replaced by a PO

If replacing/refurbishing the alternator, I recommend not discarding the original regulator. Too many issues with replacement alternators, plus I've already had two replacement Bosh regulators going bad with the brushes still in excellent condition.

[cn90]

vtl,

- I used to rebuild my BMW, Volvo Bosch alternators all the time, so very familiar with it. I used only Bosch Voltage Regulator, Nachi bearing etc.

- However, pricing for Genuine Bosch alternators have come down and very competitive.
For ex, the BOSCH AL0805N is about $240 (serach ebay and you will see $240).
This is the part that is critical to the car's function and usually replaced at 150K miles, so basically once in the life of the car, so $240 is not a bad price for a part that lasts 150K.

- Now, I buy only new (not rebuilt b/c rebuilt is done with cheap Chinese VR, bearing etc., basically a very bad job).
When looking for Bosch, look for "N" in the suffix (new) and not "X" (Rebuilt).

[vtl]

vtl,

- I used to rebuild my BMW, Volvo Bosch alternators all the time, so very familiar with it. I used only Bosch Voltage Regulator, Nachi bearing etc.

- However, pricing for Genuine Bosch alternators have come down and very competitive.
For ex, the BOSCH AL0805N is about $240 (serach ebay and you will see $240).
This is the part that is critical to the car's function and usually replaced at 150K miles, so basically once in the life of the car, so $240 is not a bad price for a part that lasts 150K.

- Now, I buy only new (not rebuilt b/c rebuilt is done with cheap Chinese VR, bearing etc., basically a very bad job).
When looking for Bosch, look for "N" in the suffix (new) and not "X" (Rebuilt).

Yeah, Bosch used to be more expensive, almost to the point where Volvo OE price was not that far away. However, the quality has dropped significantly in past 5-10 years, they begun to use cheaper bearings. I have a buddy who runs Volvo shop, they don't install Bosch anymore, because the clients do return in a warranty period with excessively loud bearings. They have a bit harsher climate then even we do in northern US, but does that matter much?

As I said, new Bosch alternator in then new 2016 XC60 was already whining.

I purchased exactly same NTN bearings that were pressed out of original alternator. Just in case added some more Mobil Polyrex EM grease, won't hurt. Old bearings were still good after 12 years and 160k miles, but the parts were already sourced long ago, and I had some free time waiting for UPS failing to deliver my camshaft lock tool due to a snow storm, so why not?

[cn90]

..I have a buddy who runs Volvo shop, they don't install Bosch anymore, because the clients do return in a warranty period with excessively loud bearings. They have a bit harsher climate then even we do in northern US, but does that matter much?

My guess is the Volvo shop installed the "X" and not "N".
In other words, BOSCH AL0805___ is available as BOSCH AL0805N and BOSCH AL0805X.

"N" is new with new VR, Nachi or NTN bearing.
"X" is usually rebuilt in a very cost-cutting approach (Chinese VR, Chinese bearing etc.).

[vtl]

My guess is the Volvo shop installed the "X" and not "N".
In other words, BOSCH AL0805___ is available as BOSCH AL0805N and BOSCH AL0805X.

"N" is new with new VR, Nachi or NTN bearing.
"X" is usually rebuilt in a very cost-cutting approach (Chinese VR, Chinese bearing etc.).

I guess, Volvo put X version into wife's new car

Out of curiosity, any chance you have (access to) N version that is about 10 years old?

[cn90]

- Back to my 2004 V70 with 105K miles...

- Serp Belt and Pulley are new.

- I didn't lock the alternator with a screwdriver but when I spun the Pulley Clutch, it seemed to "locked in", i.e., it is almost the same as a solid pulley from the good old days. Whether I spun CW or CCW, the alterntor moves along with it, so I assume my Pulley Clutch was seized in a "solid manner".

- Basically what I have now is a solid pulley, does anyone know if I can get a solid pulley anywhere as I'd like to convert to solid if possible? My 1998 S70 had solid pulley and zero issues for years and years. This Pulley Clutch system is fancy engineering for nothing (other than trying to prolong the life of an inexpensive serp belt!).

[oragex]

..I have a buddy who runs Volvo shop, they don't install Bosch anymore, because the clients do return in a warranty period with excessively loud bearings. They have a bit harsher climate then even we do in northern US, but does that matter much?

My guess is the Volvo shop installed the "X" and not "N".
In other words, BOSCH AL0805___ is available as BOSCH AL0805N and BOSCH AL0805X.

"N" is new with new VR, Nachi or NTN bearing.
"X" is usually rebuilt in a very cost-cutting approach (Chinese VR, Chinese bearing etc.).

I got a used X version, it says 'Premium' Bosch on the regulator cover. The bearings and clutch are fine but the replacement regulator has failed and it still had long brushes (it has the same numbers as the parts sold on Fcp for example, not a chinese one). The regulator is also secured with two male torx screws, I had to buy female torx sockets off Aliexpress to swap it.