Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated

Honest John Back Room » Technical matters
View Threaded
Sun 29 Jan 2012 14:11
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - Surrey_Scientist

Hi

Just been towed by the AA to my local Subaru Dealer as my aux drive belt broke.....

Unfortunately the crankshaft pulley that drives it apears to have disntegrated -I assume throwing off/breakig the belt.

Pulley seems to be a "Sandwich" construction of an outer metal drive ring with a rubber cushioning layer thats then all-bonded to the pulley that engaages on the end of the cranbkshaft. The bondng/glue appears to have come apart

I bought the car from a main-dealer in June with a years with a subaru proven warranty (its a 2005 MY car)

(A) Is this a known issue with these engines, or indeed other vehicles - I have never had/seen it happen in 20yrs of motoring on mine or anyone elses car.

(B) Is it likely that Subarus warranty will actually cover this or will they wriggle out of it and I get stung for the replacement of the puley and belt as "wear and tear"....

If they aint gonna pay fo rit to be honest I would rather get my local reapir-man to repace it as it will be a 1/4 of their dealers cost.

Cheers guys

Reply | Report as offensive | Link
Sun 29 Jan 2012 17:06
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - RT

I don't see why the Subaru dealer won't replace the pulley under warranty - from 3 years of owning the same model, well Outback version, I didn't hear of that issue.

Reply | Report as offensive | Link
Sun 29 Jan 2012 22:41
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - focussed

The type of pulley you have described is what is known as a torsional vibration damper or TV damper for short.

There are two basic types, the type you have described and have had trouble with, and the viscous fluid type, where the pulley is more like a small flywheel and has a cavity inside it where there is a heavy metal weight ring loose inside but restrained by a thick viscous fluid, this type is common to big truck engines.

Their function is to detune and reduce the twisting vibrations of the crankshaft when the engine is running at it's critical speed for crankshaft torsional vibes.

One of my vehicles is a Mitsubishi L200 truck with the 4D56 diesel and they are well known for throwing their rubber bonded crank damper in the same manner that you describe and I keep my eye on it at regular intervals when checking the oil.

Reply | Report as offensive | Link
Sun 29 Jan 2012 22:58
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - Railroad.

I've also seen similar failures on this type of pulley. It's a seven-year-old car for pete's sake. Why would you think the manufacturer would replace it under warranty? A car of this age is nearing the end of its intended design life. The fact that they do last longer is neither here nor there, but they were never intended to.

Reply | Report as offensive | Link
Mon 30 Jan 2012 07:40
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - RT

Why would you think the manufacturer would replace it under warranty?

Because it was bought with a year's warranty, less than a year ago.

Reply | Report as offensive | Link
Mon 30 Jan 2012 10:17
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - gordonbennet

''(B) Is it likely that Subarus warranty will actually cover this or will they wriggle out of it and I get stung for the replacement of the puley and belt as "wear and tear"....''

Ask them before you take it, i see no reason why a Subaru Proven warranty should not cover this.

If it was a normal used car warranty worth about the same as the paper it was printed on then doubtful it would be honoured.

Reply | Report as offensive | Link
Mon 30 Jan 2012 16:27
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - galileo

Rubber vibration dampers can be made in two ways; the bonded type relies on the adhesion of the inertia member to the hub, not unknown for this to come unstuck.

The alternative (as used by Holset) was to assemble hub, inertia member and rubber insert as a press fit, with a gullwing profile on hub O/D and outer member I/D. Believed to be more reliable unless severely overheated.

Reply | Report as offensive | Link
Wed 1 Feb 2012 20:31
Subaru Legacy 2.5 (2005) - Crankshaft aux-belt drive pulley disintegrated - Manwithaplan

Hi - had the exact same thing happen recently to my 1995 Nissan QX. Part was £187 and had to be ordered in from Japan. Garage charged £380 all in to fit along with new belts. Snapped both the alternator and power steering belt when it went.

Reply | Report as offensive | Link

Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.

The Good Garage Guide