Time to sort the cooling system on my VR6, the coolant temp. is spiking occasionally and the Oil is running hotter than I would like (108C on Motorway and 112C this morning ) ... 2 months ago I changed the coolant (so almost new (G12+ & De-Ionised Water)), flushed the system with a hose pipe (rad & engine) and put a new water pump in and new Aux Drive Belt. I've bought some 'Normfest CC442 Radiator Cleaner' from ECP to flush the cooling system (again). It says leave it in the system with engine running for 30 mins. I have some Questions-> Is it any good ? Do I use it in the system idling or drive it for 30 mins ? Which ? HELP PLEASE ! All answers appreciated as always ! [Have just bought a new Aux Water pump from ECP, a new Thermostat from the dealers and all the o-rings for the housing and sensors. So I'll fit those next week when I flush it. I will also strip down the oil cooler next week and clean that as well and finally put my last 2 Samco hoses on ! ]
i just flushed the coolant system on my A4. i always like to do a reverse flush on the radiator (hose pipe in top of rad, then hose pipe in bottom of rad, and repeat if u want), and with the engine, i took the thermostat out (otherwise your only doing half the engine) then flushed. and make sure u have the heater controls set to hot otherwise u won't flush the heater matrix. with the rad flush, they all say different things, but i assume they do the same thing. mine said fast idle for 10 mins, or drive 20 miles. i just left mine in for a day, and did a few smallish journeys.
The flush I bought said to use half so i topped up my coolant using half of it, drove for a day. drained and filled with plain water then drove that for a day. I then put the other half in the coolant and drove for another day. Next day i drained and filled with plain water again and drove it for a day. Next day I drained it all again and filled up with lovely pink ready mixed coolant from Halfrauds. keep the coolant in the car though because the level will drop and your warning light will come on after driving for a while
don't think you need to on most cars, VW's at least (since the mk2/3 polos) don't use valves to shut off the heater matrix it's just contolled by air flaps.
Thanks for the replies guys ... appreciated. I think I'll put it in the system and drive to work & back .. about 35 miles (1h10min) then flush it all. Good point about the Thermostat ..... if I drive to work that should not be a problem. When I flush it I'll be taking the system to bits (pipes off) and take the rad off and give that a good flush individually as well (forward & reverse). I intend to take the front off the car (Grill, bumper, lights etc.) to get at the rad and afterwards the oil cooler .... when I'm in the middle of changing the oil. Thanks again !
