Infamous water pump or loose belt squeal

[pleasestartnow]

So I have a squeal when the van initially starts just for the first few seconds and then no squealing for the rest of the journey or no squeal either if i go for a spin and startup again.

My Initial thoughts are loose belt (10mm x 875) until I started reading the forums and saw posts regarding it could also be water output bearings etc. I read Covkids post on the wiki and I don't have any the other issues they identify in their post. The belt was last done in 2017 and I've never had to tighten it. In terms of play in the belt I took a video of it running which you can see below and it looks like it's flapping to me. Do you think the belt looks loose there?

[JoséAhoy]

Definitely looks too loose to me, but I'm no expert! Last year I changed our belt out when it was doing this and it cured the issue straight away, but after a visit to the garage today it needs tightening again - not sure if it's common for them to need this ever so often or not? 

[maxstu]

I'm not a diesel man, PSN. But yes, the belt looks loose to my untrained eye.
The waterpump bearing failed on my waterboxer 2.1 engine with catastrophic consequences; eg: l goosed the engine, only last year. Yet a failed bearing is squealy noisy all the time. And not as your description and video.


A properly shagged waterpump bearing..

[pleasestartnow]

Thanks for that, what a dose for you like. Ya in my head I was thinking if the pump bearings are gone surely they would be squeaking continuously. But no, the pulley is solid with no play and there is no signs of any water leakage. I said I would check here with the experts before I overthink the whole thing and live in fear of the pump failing for the next few weeks. Tomorrow's job so is to try and find a new belt and replace that.

[maxstu]

Perhaps adjusting will suffice? And keep a new spare in the toolbox.

[Mocki]

I dont “do” diesels , but when i had this with one of our wbx the belt had polished the pulley , i replaced the belt with new , it did as yours is , i took the pulleys off and keyed the surfaces up , took the shine off , stopped the problem
The original issue was caused by the belt stretched and too loose

[pleasestartnow]

Spot on folks,thanks.

Perhaps adjusting will suffice? And keep a new spare in the toolbox.

I was going to do this but I think just chnage it now and then use the old one as a spare. Because I would rather anything that could go wrong go wrong now while I'm at home instead of on the motorway in France

i took the pulleys off and keyed the surfaces up , took the shine off , stopped the problem

Cheers, I will check the pulley surfaces as well and scuff them up if necessary, I definitely wouldn't have checked that.

[maxstu]

I dont “do” diesels , but when i had this with one of our wbx the belt had polished the pulley , i replaced the belt with new , it did as yours is , i took the pulleys off and keyed the surfaces up , took the shine off , stopped the problem
The original issue was caused by the belt stretched and too loose

Good call, Birthday Boy!

[tobydog]

That's well loose. It's the load on the alternator causing the squeal....

[pleasestartnow]

Cheers folks, got a new belt today but changed my mind again and just tightened the old belt up like suggested here. Started up without any squealing. Job done i hope.