VW Polo 1.4 tdi strange problem

[Smiley]

My wife was sitting in her car today with the engine idling and suddenly there was a slight but noticeable noise (grinding noise was how she described it) and a puff of white steam or smoke from the bonnet. She did the right thing and turned the engine off. Re-started it and no apparent damage - running fine.
I have had a look under the bonnet and can not find any problem; coolant level is fine, oil level fine, car drives OK - any ideas?

 

[BlackC55]

Air con pipe burst?

 

[Smiley]

Thanks Ollie - I was thinking about the a/c - unusually it was switched on when I tried the car out (after I had a good look around the engine bay) - and it is working fine so it is not that.
Bit puzzled really - I was expecting to find a shot turbo when I got home. I took the breather pipe off the top of the rocker cover and there is no cr8p in there - just a little bit of engine oil - good oil not a sticky mess of any sort.
MAy just have to see if it does it again which is a bit anoying as I prefer to nip things in the bud before they cause a bigger problem.

 

[219]

Water pump seal ?

 

[orangeboy]

Fanbelt?

 

[grober]

BE WARY since the water pump on these engines is driven off the cambelt afaik and its pretty difficult to see any problems. You don't want any engine wrecking cambelt problems if the water pump is about to give up the ghost. A good VW specialist should be able to help with advice on this. Mind you I would have expected a degree of noise from the pump under these circumstances but sometimes with diesels its hard to hear anything? the chain/toothed belt tensioners were also subject to recalls for premature failure also.

 

[Smiley]

New cam belt and water pump with metal impeller fitted about 10k miles ago. Best bet so far is sticking alternator pulley. Will take another look later.
Thanks all.

 

[grober]

New cam belt and water pump with metal impeller fitted about 10k miles ago. Best bet so far is sticking alternator pulley. Will take another look later.
Thanks all.

Might well be the ALTERNATOR PULLEY especially if its one of these fancy "overrun thingys"

 

[yachtman]

My wife was sitting in her car today with the engine idling and suddenly there was a slight but noticeable noise (grinding noise was how she described it) and a puff of white steam or smoke from the bonnet. She did the right thing and turned the engine off. Re-started it and no apparent damage - running fine.
I have had a look under the bonnet and can not find any problem; coolant level is fine, oil level fine, car drives OK - any ideas?

burst screen wash pipe?

 

[Smiley]

Might well be the ALTERNATOR PULLEY especially if its one of these fancy "overrun thingys"

Yes I think it is - but I do not too much about them. I am going to change the belt as it will have a flat spot on it for sure (I am 99% certain that this is what happened). Is it a freewheel type arrangement? Can I change the pulley only or do I need to buy a new alternator - which would mean waiting for it to seize fully

 

[BlackC55]

The pulleys can be removed but you need the kit to do it. They are bl00dy tight too!

 

[Smiley]

Thanks Olly - is it the pulley that is the problematic part?
What sort of kit is needed - is it to hold the alternator from turning?

 

[Smiley]

Now done a bit more research and it seems that these pulleys are prone to fail at around the 80k mile mark. Another useless invention - it is supposed to extend the life of the alternator but then packs up itself - and I am not epxecting it to be cheap. Plus I need to buy the removal tool. Oh well such is progress.

 

[yachtman]

Now done a bit more research and it seems that these pulleys are prone to fail at around the 80k mile mark. Another useless invention - it is supposed to extend the life of the alternator but then packs up itself - and I am not epxecting it to be cheap. Plus I need to buy the removal tool. Oh well such is progress.

i think without the free wheel pulley the stator windings get shaken to bits along with shredding the belt due to torque variations as each cylinder fires, but as ever, stand to be corrected.