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Large MPVs -- Ford Galaxy / VW Sharan / SEAT Alhambra: => Ford Galaxy / VW Sharan / SEAT Alhambra => Topic started by: Welshrob on February 16, 2014, 02:56:25 PM

Title: Mk2 TDI auxiliary belt tensioner
Post by: Welshrob on February 16, 2014, 02:56:25 PM
getting some slippage when the belt is under load (steering judder at low speed especially with heater and lights on). I've confirmed the alternator clutch but noticed the tensioner is bouncing even when not under load. Question is should it be damped? It's under spring load so is effectively keeping the belt under tension but when I move it back and fore with a 17mm spanner it feels completely un damped. Is it knackered?
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: Mirez on February 16, 2014, 04:01:15 PM
Its not damped and relies purely on the spring for tension. If the alternator clutch is goosed then you'll get bounce even when not under load.
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: Welshrob on February 16, 2014, 04:14:49 PM
Thanks for the reply. I can rotate the alternator pulley in one direction when I lock up the rotor but there is some resistance, should the clutch allow completely free rotation? Only shows up when parking with the alternator under load, worried it might be power steering related but the tensioner is bouncing all the time
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: Mirez on February 16, 2014, 04:28:36 PM
Humm it should have some resistance - for example, if you push the fan through the case with a driver, it will move but stop as soon as you do.
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: Welshrob on February 16, 2014, 05:28:38 PM
Tricky to describe but it's stiffer than that. There's definite drag probably a case of waiting for the symptoms to deteriorate a little then check if it's got stiffer. Thanks again it's my first galaxy so I've nothing to compare it with. Much appreciated.
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: steveo59 on February 17, 2014, 11:21:24 PM
Hi Welshrob,
Firstly the tensioner, the spring should be strong enough that when using a spanner to move the tensioner it should still be a struggle to pull it back and you can't hold it there for long.
Now the Alternator clutch pulley:- Release the tension on the belt by moving the tensioner with a spanner then insert a drill bit or allen key thro the hole to stop the tensioner springing back. Disconnect battery earth wire before carefully inserting a screwdriver through the air vents of the alternator to prevent the spindle turning. you can now test the alternator clutch pulley as it should turn freely one way and not at all the other. If it is tight and does not rotate freely then it needs replacing. I had this fault on mine a couple of years ago and for ages I thought it was a power steering fault.   
Title: Re: Mk2 TDI auxiliary belt tensioner
Post by: Welshrob on March 14, 2014, 05:22:59 PM
Steve, that's great thanks. The pulley is definitely getting tighter and the problem is getting worse. Will sort it out. Cheers!