Hello there! My auxiliary water pump was replaced day ago under recall and weird noise appeared.

Noise starts at 00:03 and ends at 00:56.

It looks like there is some air in aux pump or something like that.

BMW dealer said that this is "normal sound" but pump before was quiet.

What do you think it could be?

 

Sounds like there is air trapped in... Try to vent the Radiator coolant and see if it helps. They must have drained the coolant on replacing it.

 

Thanks for reply.

I've tried venting (unscrewed bleeder valve) but I'm not sure if I understand this venting. Car engine should be running when I unscrew bleeder valve?

Dealer said that they just disconnected water pump itself and they didn't drained whole system...

 

mine does this! Mini told me it's "normal" but i want it fixed!

 

Bad news... My mechanic measured CO2 gases exiting through coolant expansion tank. It looks like there is some exhaust leak mixing with coolant water.

Mechanic said there is PROBABLY bad cylinder gasket.

 

warming mine up as we speak, gonna do a smell test and check tank for bubbles... its the same as how we used to test older cars for head gasket leaks into the water jacket

 

**** me.... i have the same problem... plus my coolant is dark and has dirty flakes in it... only 5k miles

 

Sorry to hear that :( i have 50k kilometers.

Head, intake and exhaust gaskets must be replaced. Gaskets are relatively cheap, but work will be very expensive.

BTW - how did you do that buble test in expansion tank? K would like to test it too.

Your pump was changed too? Your car is under warranty, so you're fine

 

take off the overflow tank cap, since it's also basically the radiator cap, and warm the engine up... when the thermostat is open look into the tank at the coolant and you'll see movement from the gasses coming in... very small bubbles... you can also see the vapor gasses escaping, although hot coolant will look like this too.. but the smell is different.

 

and followup: used the block tested coolant test (sniffs air from expansion tank for exhaust gasses) with a positive... off to mini

 

I was in another garage yesterday and they did block test (measured gases in coolant tank) and the result was negative.

So I really don't know what to do now. Car is running fine, no coolant leaks, no mixing with oil, no white smoke from exhaust, no power loss... nothing!

I've also found black particles in coolant tank and my coolant turned to dark color.

@avenger - Please let me know what did they say in Mini.