Low whining noise

[richandhazel]

I can't be the only one that has come across this low whining noise from the engine of my Mk1, especially as my girlfriends Audi makes the same noise (basically the same engine). It varies with engine speed and I initially thought it was the alternator bearing. However on removing the fan belt and starting the engine momentarily, the noise is still evident. I've now traced it to the timing belt tensioner. Against my own advice I didn't actually change the tensioner when I changed the timing belt as it looked and felt OK. Today I tried 2 other tensioners that I robbed off 2 spare engines that I have and the noise is still there.

Has anyone had experience of this and do you reckon if I actually get a new one it'll fix it? I don't really want to buy a new one only to find its the same as apart from the noise, the one thats on there seems fine.

[mk1]

Timing belts to tight can make a humming noise, worth a look. Steve.

[richandhazel]

No its definately the tensioner or something to do with the timing belt.

Are you sure its the engine and not the gearbox? Is the noise still there with the clutch depressed? It probs is a good idea to replace the tensioner with a new one anyway.

[richandhazel]

Ah, thats a good point, I do tend to overtighten rather than under tighten the belt......I'll try loosening just a tad.

Timing belts to tight can make a humming noise, worth a look. Steve.

[Justins145bhpMK1]

LEt me know how you get on Rich, mine does exactly the same!!!!

[richandhazel]

Well done, spot on........just slackened it off a little and the noise has gone.  

Timing belts to tight can make a humming noise, worth a look. Steve.

[richandhazel]

Now just done the Audi too and success. I've been overtightening the timing belts..........there so quiet now.