N54 Water pump preventive replacement

[Dylan R. Fisher]

Hi forum,

I've got 35i 2010 that's officially ticked over 80k miles. As third owner of the vehicle I have no idea whether the water pump/themostat had ever been changed.

Reason for the potential change would be due to a noise i've heard coming from the pump with the engine switched off after a hot run when oil temps would reach around 120-125 Celsius.

I'm aware the pump should continue working after engine shutoff to compensate for the lack of frontal airflow, but the noise seemed somewhat louder than usual.

I might be mistaken but Continental supply the OEM water pump, but I've read else where that Pierburg supply a better all metal version.

Anyway any advice on parts, or processes in checking the pump would be greatly appreciated!

Thanks

[B21]

Hello and welcome..

Yes Pierburg do an all metal pump, several of us have fitted it..one person did have an infant mortality issue.

Best to replace the thermostat at the same time.

About a 5 hour job for most folks.

Usualy the first sign of failure is the coolant throwing up through the header tank.

At that time a decent fault code reader will show some pump related error codes.

However on cool down the pump may stabilise and not show any codes..but the frequency of failure will increase.

Mine failed without warning at 60k miles at the furthest point from home on the NC500....

[Dylan R. Fisher]

Thanks for the prompt response!

Ok, I think its worth getting changed out, might also replace the plastic coolant flange that connects to the oil filter housing unit too.

Would you recommend a site where to buy the pump and thermostat?

Cheers!

[B21]

Thanks for the prompt response!

Ok, I think its worth getting changed out, might also replace the plastic coolant flange that connects to the oil filter housing unit too.

Would you recommend a site where to buy the pump and thermostat?

Cheers!

Autodoc via their smartphone app is your best solution if time is not critical…the smartphone app offers deeper discount than their web pages..

They offer various discounts on a daily basis…they can hit 40%+ so I’d put the parts on their ‘watch’ list then press the go button when you feel lucky…

[Dylan R. Fisher]

Thanks for that.

Would you recommend the OEM thermoset as well?

Thanks.

[B21]

Personally I would go with the Mahle version in this case..tier 1 supplier to BMW and others..don’t want to be revisiting that m.f.

[Dylan R. Fisher]

https://www.ebay.co.uk/p/19042462414 - I found Pierberg pump on ebay. Think i'll go for it.

[B21]

https://www.ebay.co.uk/p/19042462414 - I found Pierberg pump on ebay. Think i'll go for it.

Good price..