Alternator Pulley Fell Off Topic is solved

XC70Rider · Post by **XC70Rider** » 27 Oct 2020, 15:08

On the way to work the alternator pulley fell off
I feel no damage to the clutch bearings and no damage to the pulley threads. Can I just turn the pulley back on alternator, throw on new belt and drive safe for a few days? I ordered a replacement kit from FCPEURO 30667878 that I'll get in 2 days.

Being towed home while writing this thread.

Post by **RickHaleParker** » 27 Oct 2020, 19:15

You have the right tools to tighten it?

XC70Rider · Post by **XC70Rider** » 27 Oct 2020, 19:27

The kit I ordered comes with the thread w splines and the 10mm stud. Tonight I just hand tightened the pulley while holding the clutch fins held in place.

I found no damage to the clutch nor pulley bearings and belt had no cracks. I threw the belt back on and drove for 5 miles tonight. No squalling while idling and all pulleys are in good shape.

The pulley threads back on CCW in same direction as the belt flows. Scratching my head on how it fell off in the first place?

Post by **RickHaleParker** » 27 Oct 2020, 23:29

XC70Rider wrote: ↑27 Oct 2020, 19:27 Scratching my head on how it fell off in the first place?

When the belt slows down, the inertia of the Alternator Rotor produces a relative CW spin between the shaft and pulley.
Indicates the pulley is not “free-wheel” or “overrunning” like it should.

Post by **darrylrobert** » 28 Oct 2020, 05:27

you can drive the car about 100km without an alternator, thats without using headlights/turn signal/radio/seat heater/avoid using brake light .

XC70Rider · Post by **XC70Rider** » 28 Oct 2020, 17:54

With oe pulley and replaced belt thrown back on I drove 190 miles to and from work with no issues today.

At 146k miles the alternator might not last much longer so I ordered a new Boach from FCPEURO. I'll throw on the new alternator with a new belt and tensioner this weekend.

I'll rebuild the OEM alternator and keep it for backup. I'll search tor threads on what else to replace along with a new pulley and voltage regulator.

Post by **cn90** » 28 Oct 2020, 19:20

Agree with new alternator.

Pulley: life is about 140K-160K as you have learned.
Alternator lifespan is about 180K-200K (bearings, brushes etc.), the VR can fail any time between 100K-200K.

So a brand-new alternator is the way to go, less future headache.

I guess you can return the pulley (FCPEURO 30667878).

Post by **ljsommar1** » 29 Oct 2020, 09:00

The pulley on my alternator came off while I was about 90 miles from home. Almost unbelievably I was able to make it home. The serpentine belt still drove the alternator shaft. I did not even discharge the battery.
I ordered a new (not rebuilt) and have not had a problem since, about 30K miles. I rebuilt the original to have as a spare. It is worth noting most alternators sold are rebuilt units and most do not replace the bearings and if they do, they use cheap Chinese ones.

Post by **xHeart** » 29 Oct 2020, 10:58

XC70Rider wrote: ↑27 Oct 2020, 15:08 On the way to work the alternator pulley fell off

Why would a pulley fell off? how old is the tensioner?

ignatz · Post by **ignatz** » 29 Oct 2020, 12:04

I also had a clutch pulley grenade on my past 2001 V70. I heard a noise in that area, but somehow I thought the power steering pump was making the noise. I was changing the power steering fluid and no improvement was made. Not too long after that, the clutch pulley gave loose.
I also remember that the shop put on a rebuilt alternator with a solid pulley. They probably figured that I don't go over 3 grand too much.