I emailed my local stealers for prices on service parts I'll need for my vrs and for a cambelt kit and water pump, and after reading a few posts on here with regards to getting a water pump with a metal impeller etc I asked for a price on one. They emailed back with prices but said they don't sell or advise using pumps with metal impellers because if the impeller was to break, it would 'cause considerable damage to the engine'. I can see where they're coming from but it seems a bit contradictory to what I've read before and surely a metal impeller would be less prone to breaking in the first place, compared to a plastic one?

Anyone have any views on this?

I thought that all the oem impellers were metal now??

I think they charge a surcharge for water pumps from the dealer at the moment, so you must have a genuine pump to give back to them..

Oh right, well the jist I got from the reply was that they were plastic. They also said that the water pump is a special order exchange item, and that they'll need my old one before they give a 'new' one out

I can vouce for alot of the newer ones being metal, can't say 100% for all vag cars but vauxaull and ford have had metal ones on cars I've worked on.

When I got one from TPS back in May last year, it had a plastic impeller. Also there was a surcharge which was refunded when I returned the old pump.

I though the issue with the water pumps was when they weren't changed with the cambelt, as long as they are changed with the belt then there is very little chance of them disintegrating.

metal impeller > plastic impeller.

All the ones the dealer will sell you are plastic, always have been and still are. If you want metal then you'll have to go aftermarket with the risks associated with those.

I'd stick with the plastic, after all the old one has been fine and a new one will last just as long. Replacing with metal, may mean the impeller lasts longer but then something else like the bearings could fail anyway.

OEM are plastic..................the failure is down to the plastic blade detatches from the metal knurled spindle......the blade chews itself up and the temps of the engine rise.........

Metal ones dont have the problem of the blade detatching..........BUT if the blade "snags" on anything eg a bit in the liquid or it goes off balance and hits the sidewall then the blade sticks which causes the timing belt to jump/strip and then the valves and pistons kiss!!!!

Plastic all the time!!!!

I've never ever heard of anything detrimental happening to a car running with a metal impeller though! All across the VAG range of cars, people are moving to metal impeller type. I was under the impression these were available, and were an update on the original plastic ones from the dealer though.............. May be worth contacting your local VW dealer and asking their opinion

We use plastic ones at the dealership I work at.

ive just picked up a genuine vw pump for my 1.8t and that as a metal impellor. wonder if diesel only have plastic?

I asked at tps today. On some engine types the metal impellers are optional. The 1.8t one I bought a while ago was metal too but the one I took back for surcharge had a plastic one.

IIRC the one I took out of my old car was metal and the new one was plastic.

But I'm not sure where the metal one came from (it was changed at a mates garage and I don't know if he used genuine VAG parts).

Fair enough, thanks for the replies. Think I'll just stick with an OEM plastic one then!

How many people have had a failure with a plastic pump blade to warrant all the fuss I wonder

I have seen plastic ones fail, they go brittle with all the constant heating/cooling cycles, but if you replace them at the right intervals along with the timing belt they don't really cause a problem..

I've seen metal impeller pumps fail too and when they go it's fairly spectacular.