XSeries-forum

Hi guys

I've got to replace the thermostat on my E53 3.0d so think its a good idea to change coolant at the same time as it also doesn't have the correct BMW coolant in it at the moment.

I've done it before on other BMW's so am OK with that and bleeding etc.

However does anyone know where the drain plug for the engine block is on this engine?

I remember it being an awkward bugger to find on both my 330ci and my M3.

All I can find through a search online as on all the guides I've read suggest just draining it out of the rad and filling will distilled water, then running it, then repeating until its clear and then tipping the coolant it which seems a bit long winded to me, unless of course the drain plug on this is a real bitch to get to?

Cheers

Ben

Any use? https://www.pelicanparts.com/techarticl ... System.htm

sleepyfolk wrote: ↑Wed Jan 23, 2019 11:07 pm Any use? https://www.pelicanparts.com/techarticl ... System.htm

Thanks mate. I've seen that but it's for a petrol x5 I think.

To be honest I'm probably just going to leave the block drain alone and flush it out with deionised water before putting coolant in.

Got it sorted but it was more of a ballache than first anticipated.

Tried the drain plug on the radiator first which snapped off leaving the thread in.

Then tried the lower rad hose which wouldn't budge.

Ended up removing the thermostat which was easy enough which I think emptied most of the coolant out the block. I then topped up with water and ran and drained again by disconnecting the lower hose on the thermostat.

Gave it a few goes and filled back up with 50% concentrated BMW coolant now.

Car gets to temp much quicker and the needle stays in the middle so hopefully I might squeeze a few more MPG out of it too!

Too late now but the block coolant drain bolt is on the side of the block under the turbo, not far from the turbo oil outlet pipe.

For the plastic radiator drain, use a socket rather that a screw driver (it has both a hex head and crossed slots) - it's less likely to strip out.