Leak in Expansion Coolant tank

[jmello21]

Hello all...

I currently noticed a leak in my expansion tank when I saw my car kept having water puddles. I filled it up and it has a small pinhole where it leaks. I ordered a new tank and should get it soon. I got a low water signal from my x5 when it was empty so I refilled it.

Question: am I ok just putting in water and filling it up to drive to work and back? Or could it compromise my engine? I have no idea how to track how hot my engine is getting. Is that possible?

Any help is appreciated! Thanks.

J

[Road Ruler]

Hello all...

I currently noticed a leak in my expansion tank when I saw my car kept having water puddles. I filled it up and it has a small pinhole where it leaks. I ordered a new tank and should get it soon. I got a low water signal from my x5 when it was empty so I refilled it.

Question: am I ok just putting in water and filling it up to drive to work and back? Or could it compromise my engine? I have no idea how to track how hot my engine is getting. Is that possible?

Any help is appreciated! Thanks.

J

I had the same problem with my 2010 a few months ago. To be safe I filled the expansion tank with water and made the 10 min drive to the dealer. They fixed it under warrantee. I had a 30 day warrantee from the dealer when I bought the X 28 days earlier. They replaced the expansion tank, flushed out the cooling system and refilled with fresh fluids. Bill was 800. at the BMW dealer but no cost to me.

[JoeyBimX5din]

I think you will be OK for just a little bit. If you put to much water into the system, maybe when you replace the tank, it may be a good idea to complete a drain and refill, just to get your %'s correct. I would not go much longer then maybe a week or two doing that though.

[werdn]

I have a 2007 BMW 4.8 X5 (Pre-Facelift), I just changed the expansion tank today. I think filling your expansion tank with just water is kinda dangerous because water boils at 100 degrees C, and the coolant in my X5 normally runs at 102 degrees C (I checked with a OBD 2 scanner while driving on flat, uphill, downhill roads). At normal operating temperatures, the water inside the expansion tank would be boiling. The purpose of coolant is to raise the freezing point and the boiling point of the liquid inside the expansion tank. I think a reason why you have puddles of coolant is because your car is overheating, and coolant is forcing its way out of the tank.

BMW coolant is not that expensive on Amazon, and I think there is Prime 1 day shipping on it too. In the worst case scenario, stop by an Autozone on the way to work and buy some coolant there. When you have time, bring it to BMW, have them flush the coolant and refill it with the OEM BMW coolant.