When I purchased my car I was informed it had the oil cooler changed due to a previous leak. A common fault on the 4.4 TDV8 it seems from my searches on this very forum.

The inside of the coolant expansion tank, however, is coated with oil because I assume it was not changed as part of the repair. I plan to flush the coolant system but wanted to achieve the best results so wonder if there is a special flush, an additive, or other tricks to give the system a good clean out rather than just using water?
I expect I'll need to replace the expansion tank due to staining, unless anyone thinks its salvageable?

As I also have squeaky idler pulleys I am planning to strip and replace them along with the belts (and with the AC compressor due to intermittent cold air) so may as well do the coolant flush at the same time.

I hadn't planned on replacing the oil cooler or gasket as it was apparently done, but should I consider doing something there just for peace of mind? and what about the water pump? is that something to consider too?

I am not wanting to replace parts for the sake of replacing them, but don't want to get a few months down the line to find I have to strip it all again... Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html

My car sounds as though it has had the same experience as yours. I tried everything to clean the expansion tank and failed so I put a new one on. I'm slowly collecting all the pulleys together to do them all at the same time. I've got a genuine water pump and tensioner so far. I was sent a pattern tensioner by mistake and the quality was very poor compared to the genuine one so would advise to buy genuine only.
I know the parts are expensive but my car is a keeper and I only want to do it all once.

When my oil cooler was replaced, the garage had to flush the cooling system 3 or 4 times to get rid of the oil. They used a coolant flush, but don’t know any more im afraid. I then ran it for a year and then had coolant changed again, just to be sure.

I too have the delayed air con… fine when it comes through 🤣

 2011 Range Rover Vogue SE 4.4 TDV8

Previous cars :
2003 Range Rover Vogue TD6
1999 Discovery Td5 ES
1995 BMW M5 3.8 6 speed
1992 Range Rover 3.9 Efi Vogue
1992 BMW M5 3.8
1988 BMW 735i SE
1989 Ford Sierra XR4x4 2.9i
1981 Ford Fiesta Supersport

In the past, I've used dishwasher powder to good effect  Kev

2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey

Best way I have found is flush out with plain water then add a tin of petrol injection cleaner ( I kid you not) run up to temp and let it idle for 10 minuets or so then flush with plain water several times next add normal rad flush run up to temp again and flush out well with plain water, it will even clean out the expansion bottle.

knwatkins wrote:

In the past, I've used dishwasher powder to good effect

Thanks for the suggestions so far!
Who would have thought to use washing powder! But, it does get out stubborn stains so why not!!!
Do you simply flush with water afterwards? Is there any contamination risk? Currently driving: 2012 L322 SE Overfinch 4.4 tdv8

Past rides:
2014 Audi Q7 3.0d (good riddance)
2010 L322 Autobiography 5.0 Supercharged
2011 L320 HSE 3.0 sdv6
2014 Jaguar XF-RS 5.0 supercharged
2007 BMW 535D
2005 Mini Cooper S

https://www.fullfatrr.com/forum/topic59478.html