W220 Cooling system flush.

[BelfastBill]

Hi, well I have just had my new oil cooler and hose fitted, but there is gunk in the header tank and probably in the cooling system,any ideas the best way to get rid or flush the system out.I was going to get a new header tank but would want to flush the whole system out.
Thanks for any help.
Bill.

 

[BelfastBill]

Anyone know what the temperature gauge should be sitting at on The 648 320cdi engine please.

 

[markjay]

Drain, fill with tap water (soft water - if you can get it), add a bottle of cooling system flush, drive the car with the cabin heater on full (highest temp), let the engine get properly hot. Allow to cool down.

Drain, repeat the step above but this time without cooling system flush. This step will remove any leftover of the flush.

Drain, refill with coolant. If not using ready-mixed coolant, keep in mind that there will be *some* water left in the system, so you can go for (say) 55% concentrate and 45% water. The way I mix them (when not using ready-mixed), is by adding the contents of one small bottle (330cc or 500cc) of each at a time, i.e. alternating between coolant and soft water, instead of mixing it in advance outside the car.

Once done, bring the engine to working temperature, allow to cool, open the expansion bottle and add coolant mixture up to the mark. Check for any leaks around the pipes and under the car. Job done.

Note that depending on your car, there may be a drain plug at the bottom of the radiator, or you may need to disconnect the lower house pipe for draining.

And, the issue with old expansion bottle is that they become brittle over time and crack, so you might want to consider replacing it with new rather than cleaning it (depending on its age).

Also, coolant is toxic for both people and animals, it is especially dangerous for pets who are attracted to the taste, so dispose of it carefully and responsibly and do not let it spill on the drive where a cat or a dog might lick it up. Also, never store coolant in food containers (e.g. old water bottle etc).

 

[BelfastBill]

Got it sorted, thanks for making the effort to help.