While driving on the freeway for about 45 miles, I heard a quick screeching and a clunk, and then the computer said there was an electrical system loss. I pulled over and found that the free wheel pulley had spun off of the alternator. The belt was intact and did not look damaged. After quite a bit of research, I've come to the conclusion that one of two things happened: a) the pulley bearings got hot and didn't allow the pulley its reverse spinning motion, or b) for some reason the alternator stopped rotating and spun the pulley off. The alternator spins currently with no apparent resistence, and the pulley bearings aren't so tight that I can't move them. Struggling to figure just why such a symptom would occur, since the belt constantly applies positive force to the left-hand threaded pulley.
So, I'm looking for advice on two fronts. First, if I simply need a pulley, how can I diagnose the old pulley? Second, if I need an alternator, there is a wide range of pricing out there with the Volvo dealer topping the list at about $550. If the pulley is bad, it's $90 at the Volvo dealer, but I don't have the tool (so I guess I'd be stuck with them doing it).
Thoughts on after-market re-manufactured alternators? Thoughts on pulley diagnosis?
2004 V70 2.5T FWD
68,888 miles
Vancouver, WA
V70 free wheel alternator pulley spin off repair advice
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RaymanSean
- Posts: 246
- Joined: 26 September 2010
- Year and Model: V70 XC, 2001
- Location: columbia, sc
I don't know what you mean by free wheel pulley. If you mean the pulley that bolts onto the front of the alternator, then chances are that it was not torqued to the proper specification.
Yeah, I had no idea about it either. For an interesting post on VW's that have the same style pulley, check this out:
http://forums.tdiclub.com/showthread.php?t=139424
The pulley "is" the nut.
http://forums.tdiclub.com/showthread.php?t=139424
The pulley "is" the nut.
'04 V70 2.5T
'92 245
'74 145
'92 245
'74 145
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JRL
- Posts: 9350
- Joined: 22 November 2005
- Year and Model: Several
- Location: 19333
- Been thanked: 16 times
I'm not 100% sure what you're saying here but the pulley is part of and comes with the alternator.
It sounds as if the pulley may have seized (pretty rare) then snapped under load.
You probably need a new (or used) alternator
It sounds as if the pulley may have seized (pretty rare) then snapped under load.
You probably need a new (or used) alternator
Mod note. Jim passed away in early 2022, his contributions to this forum are immortal, and he is missed. RIP
2000 V70R Black, 144,000 miles Wife's R.
2007 V70 2.5T White/Oak 111,000 MILES. Polestar tune, IPD bars, rear spoiler, dark grey Thors, DWS 06, HU850, sub.
2000 V70R Black, 144,000 miles Wife's R.
2007 V70 2.5T White/Oak 111,000 MILES. Polestar tune, IPD bars, rear spoiler, dark grey Thors, DWS 06, HU850, sub.
Yep, again, this is a weird situation. The pulley didn't snap, it "spun" off. Unthreaded itself. It has not seized, as it can be rotated. I have threaded it back on as far as I can get it without the tool. I guess I'm trying to avoid the expense of a new alternator if someone can help me diagnose the pulley.
'04 V70 2.5T
'92 245
'74 145
'92 245
'74 145
Guys, please forgive the revive on this old thread, but I'm a new Volvo owner and need help. I had this exact thing happen to my 'new' 2005 V70 (2.4L non-turbo) a couple days ago and the car is parked.
Started the car, heard thumps and flapping noise, and immediately turned off the ignition. Upon inspection, pulley wheel had unthreaded (!?) from the alternator and was lying on the ground under the car, serpentine belt hanging! There is a fine reddish dust around the alternator thread area, and the threads look slightly cross-threaded, but the alternator rotates fine, and the pulley wheel seems intact. I really don't want to buy a new alternator if all that's needed is a reinstall of the pulley wheel.
So, a few words of guidance from some of you Volvo experts will go a long way. What should I do? Is this a sign of bigger issues? How the heck do I get that wheel back on? What size/type of wrench do I need, etc?
Thanks in advance, and I'm thrilled that this site has a thread regarding my exact issue!
-D
Started the car, heard thumps and flapping noise, and immediately turned off the ignition. Upon inspection, pulley wheel had unthreaded (!?) from the alternator and was lying on the ground under the car, serpentine belt hanging! There is a fine reddish dust around the alternator thread area, and the threads look slightly cross-threaded, but the alternator rotates fine, and the pulley wheel seems intact. I really don't want to buy a new alternator if all that's needed is a reinstall of the pulley wheel.
So, a few words of guidance from some of you Volvo experts will go a long way. What should I do? Is this a sign of bigger issues? How the heck do I get that wheel back on? What size/type of wrench do I need, etc?
Thanks in advance, and I'm thrilled that this site has a thread regarding my exact issue!
-D
I'm sorry to say that I didn't choose to go the difficult route on this one -- I took it to one of the area Volvo shops. about $600 dollars later and I had a refurbished alternator. The job is quite a bit more difficult that you might think. When the shop explained it to me, I felt better about leaving this one to a well-equipped shop. The components above the alternator must be moved out of the way, and the alternator itself must be slid all the way across the front of the engine (left to right as you face the front of the car) to remove. Not remembering exactly, but I think the coolant hose must be removed as well. Anyway, it was WAY more job than what I had thought a simple alternator replacement would be, having done several on other cars. The bearings on my pulley were no good, and there was no fix for just the pulley that I could find. Good luck!
'04 V70 2.5T
'92 245
'74 145
'92 245
'74 145
Well,
I went the $15 route, and found the tool on amazon. Posting here for others who need it:
https://www.amazon.com/CTA-Tools-8088-Al ... ulley+tool
Ended up pulling the pwr steering pump and removing the alternator so I could tilt it and access the alt pulley wheel. Good to go!
Installed everything, new belt and plugs from IPD along with an oil change....nice Saturday getting acquainted with my new Volvo.
Looks like it wont be the last Saturday I spend, as the crankcase pcv hose (?) disintegrated as I was reinstalling the cover. WTF!@?? Might be looking at a PCV issue soon. Hope I can drive this thing with half the hose gone...
I went the $15 route, and found the tool on amazon. Posting here for others who need it:
https://www.amazon.com/CTA-Tools-8088-Al ... ulley+tool
Ended up pulling the pwr steering pump and removing the alternator so I could tilt it and access the alt pulley wheel. Good to go!
Installed everything, new belt and plugs from IPD along with an oil change....nice Saturday getting acquainted with my new Volvo.
Looks like it wont be the last Saturday I spend, as the crankcase pcv hose (?) disintegrated as I was reinstalling the cover. WTF!@?? Might be looking at a PCV issue soon. Hope I can drive this thing with half the hose gone...
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sleekitwan
- Posts: 6
- Joined: 10 April 2013
- Year and Model: V70 D5 2003
- Location:
Okay, I have a think, I saw this a fewminutes ago, and yes, the result is you need a new 'clutch pulley' because of the reason the thing spun off.
Consider for a mo, the situation where the engine is running normally and the freewheel aspect is also fully functioning. When the need arises for the freewheel to be used (the belt turning it slows leaving the alternator to spin a little under its own momentum), there is no problem.
Just remember though what this means - in effect THE BELT IS GOING IN REVERSE COMPARED TO THE CLUTCH PULLEY. Fortunately, even though the pulley is only tightened on with a thread screw (like a bicycle pedal screws in - on one of the pedals it's the 'wrong way round' to normal tightening), it does not matter, the freewheel ensures no significant force turns the clutch pulley the way that would make it 'unscrew'.
BUT when the freewheel mechanism SEIZES or at least becomes rough enough/rusty enough to offer enough torque to unscrew, then it will. Now that explains the strange phenomenon of the 'self-unscrewing' clutch pulley - the thing gets old and rusts or gunks up, some of them are so rusted onto the threads they STILL won't come off, in those cases the belt is forced to slip over the pulley instead, until it breaks.
BUT in these cases, it unscrews the thing because the locked-up mechanism allows enough torque to be applied - in the correct direction for unscrewing - to spin it off the alternator threaded shaft.
As to why it appears in some cases to be perfectly rotatable by hand once it has spun off, I can only surmise that at SLOW speeds the mechanism appears fine. Unless I am much mistaken, these things are like the old braking system on bicycles, where for a rear brake, the person simply reverse-pedalled, and the thing would brake the rear wheel.
The device 'throws out' some metal rollers when spun in the opposite direction to normal, and when these contact, they will lock up with the casing around them (the inside of the small ribbed drum that we see as the clutch pulley). So, it seems to me, the freewheeling clutch pulley is the bicycle rear hub but working in reverse ie NORMAL action is to be locked up, but when the belt SLOWS, the metal rollers are permitted to disengage.
So, there is an element of CENTRIFUGAL FORCE (centripetal acceleration to the Engineers or physicists), and that won't happen when you turn the thing by hand.
Hope this helps. In short - I have explained ONE of the issues experienced by a particular contributor (the clutch pulley problem) but not why he got charged ALSO for a whole alternator.
The explanation is either the alternator experienced a similar amount of rusting to its bearings as the clutch pulley did, or of course the dealer got greedy. Either is possible, I know not which actually happened. The only other point is, if the alternator is seizing, the pulley gets a hard time, and if the pulley is seizing, the alternator gets a hard time. Whther it's bad enough to cause failure though is unanswerable by me.
Consider for a mo, the situation where the engine is running normally and the freewheel aspect is also fully functioning. When the need arises for the freewheel to be used (the belt turning it slows leaving the alternator to spin a little under its own momentum), there is no problem.
Just remember though what this means - in effect THE BELT IS GOING IN REVERSE COMPARED TO THE CLUTCH PULLEY. Fortunately, even though the pulley is only tightened on with a thread screw (like a bicycle pedal screws in - on one of the pedals it's the 'wrong way round' to normal tightening), it does not matter, the freewheel ensures no significant force turns the clutch pulley the way that would make it 'unscrew'.
BUT when the freewheel mechanism SEIZES or at least becomes rough enough/rusty enough to offer enough torque to unscrew, then it will. Now that explains the strange phenomenon of the 'self-unscrewing' clutch pulley - the thing gets old and rusts or gunks up, some of them are so rusted onto the threads they STILL won't come off, in those cases the belt is forced to slip over the pulley instead, until it breaks.
BUT in these cases, it unscrews the thing because the locked-up mechanism allows enough torque to be applied - in the correct direction for unscrewing - to spin it off the alternator threaded shaft.
As to why it appears in some cases to be perfectly rotatable by hand once it has spun off, I can only surmise that at SLOW speeds the mechanism appears fine. Unless I am much mistaken, these things are like the old braking system on bicycles, where for a rear brake, the person simply reverse-pedalled, and the thing would brake the rear wheel.
The device 'throws out' some metal rollers when spun in the opposite direction to normal, and when these contact, they will lock up with the casing around them (the inside of the small ribbed drum that we see as the clutch pulley). So, it seems to me, the freewheeling clutch pulley is the bicycle rear hub but working in reverse ie NORMAL action is to be locked up, but when the belt SLOWS, the metal rollers are permitted to disengage.
So, there is an element of CENTRIFUGAL FORCE (centripetal acceleration to the Engineers or physicists), and that won't happen when you turn the thing by hand.
Hope this helps. In short - I have explained ONE of the issues experienced by a particular contributor (the clutch pulley problem) but not why he got charged ALSO for a whole alternator.
The explanation is either the alternator experienced a similar amount of rusting to its bearings as the clutch pulley did, or of course the dealer got greedy. Either is possible, I know not which actually happened. The only other point is, if the alternator is seizing, the pulley gets a hard time, and if the pulley is seizing, the alternator gets a hard time. Whther it's bad enough to cause failure though is unanswerable by me.
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