[moved] COOLANT TURNS TO BROWN SLUDGE

[melvr6 0]

Has anyone encountered this problem before and if so, how did you fix?

My VR6 developed a coolant leak from one of the rubber pipes. As an interim measure until I could replace, I bought some antifreeze from local spares (not G12 as I now I should have bought) dealer which is supposed to be for universal application. A day after topping up the coolant changed to a brown muddy / oily sludge throughout the cooling system.

There seems to have been some chemical reaction with the water, mixing of the antifreeze and heat. So now I have one hell of a problem. This sludge does not flow and is not flushed by water.

Questions:

1. How does one clean / flush this from the entire system?

2. How will it affect parts like - Radiator core, thermostat, heater pack in A/C, water pump, temp sensors and engine block cavities?

Can anyone assist?

Cheers

[shail 0]

Apart from removing pipes to locate the blockage I couldn't tell you, but, my coolant is always a brown colour. I have flushed it and purged it so many times over the years, but it remains brown, but is not blocked. I guess the previous owner did the same as you. So once you un block your system, be prepared for it always going brown.

Also, you need to buy G12+. The 'plus' is important as it can be mixed with older G11 and G12. Its been a while since I bought it, so there may now be an imprved version of G12+

[thegoth 5]

yep, there is now a G12++

[rodney 17]

well the word sludge worries me..

There are coolant system flushes that you can buy. To make your own life simple do the coolant system in parts if practical.....

I would empty and drain and clean as many componant parts as practical. Radiator off thermostat housing off pipes off ... you get the picture...

Then over a period do the sealed system once or twice in line with the manufacturers instructions...

http://www.wynnoil.co.uk/cooling_system.htm

it is while since I have flushed a system but here we go for a link.. Perhaps it may be worth pm'ing the chaps who work in the trade as which brand they suggest for the dub

Hope it helps

[Saunders82 0]

part number g052188a3 from vw is the proper vw coolant flush its abit pricey ( i cant remember exacly but i know its around £25)

it is how ever the bollocks ! i sell it when ever the oil coolers on pd diesels start mixing oil and water

newest part number for g12++ is g012a8gm1

dont mix anything with g12++ other than more g12++ and water!

[dru 0]

probally not relivant but i had the same problem on my seat ibiza did an full flush and less that 24hrs later the same again turned out it was the headgasket that had gone and oil and leaked into the coolant

[xyber 1]

Sounds like you've mixed different types of coolant, G12+ is non reactive so can be used without worry, but others, when mixed, turn into a nasty, highly caustic sludge, I'd flush it ASAP

[melvr6 0]

Hi Everyone. Thank you to all for your comments and advice on this problem.

I have had my VR6 delivered to my tuner on a rollback to eliminate any further problems occuring. They will start a flushing process today - this may take several days as I want to make sure everything is cleared, cleaned or replaced before I fire up my baby again. We ran some tests on the sludge yesterday and it seems that the only thing that may work to flush it all out, with any degree of success, is engine cleaner.

I also have only been able to source G12+ coolant at this stage and this too is pretty expensive. Have not found G12++

Have a great weekend.

Cheers for now