Hi All,

I've got a 2009 R56 S, it's been leaking coolant. First I noticed the fan spinning up quite a bit. I got a temperature notification a few weeks ago (yellow, not red) and cleared it - as soon as speed picked up it did not come back. Coolant was low and I added some distilled water the next day. About 100 miles later, it's low again.

I added more this morning but when I pulled back in I'm noticing two things. First is that there is a steady stream of drops coming from the middle/driver side of the engine dripping beneath the car. Second, the car is making a bit of an air bubbling/seeping noise from roughly the area of the thermostat housing when the hood is open.

I am fairly certain it's not the water pump as when I squeeze the upper coolant hose (near back passenger side corner of engine) with the engine running it builds pressure after a few seconds.

I'm going to go ahead and do the thermostat housing - should I be order any other parts immediately, such as hoses? Pretty sure bet I've got a leaky thermostat, right?

Thanks all!

 

I just changed out the coolant pipe and thermostat housing a couple of months ago on the wife's R56 (non-S). The S version will be slightly different in terms of disassembly but there are tons of youtube videos to help. The thermostat housing is fairly easy to change, it's just have you have to remove a good amount of things to access it. based on what you mentioned, it seems like it is the thermostat housing.

My thermostat housing was starting to separate at the seams so that's why I replaced it.

Other parts that you should buy would be an extra housing gasket. The cutout where the housing sits on the engine has some sharp edges. When I first installed it, I had troubles getting it on the coolant pipe, so when I was jiggling it around, it cut the gasket. I put everything back on and it started leaking at the gasket. Luckily, I had an extra one so I disassembled it and reinstalled it being a little more careful.

I would also suggest doing the coolant pipe at the same time if you can. I didn't have much issue since I have small hands and arms, but it can be a bare to fit it to the water pump.

 

I agree with dcwang3 regarding changing the pipe at the same time, even if you end up pulling the intake manifold to do it.

Also, I highly recommend buying an original equipment supplier thermostat and pipe.....speaking from experience.

 

I was able to change the pipe without pulling the intake manifold. Have to raise the front passenger side, take off the wheel and fender liner, and you will be able to see and squeeze your arms to help force the pipe into the backside of the water pump.

for the thermostat, it’s probably a toss up. I’m using a Rein thermostat, having to replace it after 2 months. Thermostat is stuck open but it’s nice that FCPEuro does the lifetime warranty.