Coolant Flush

[omegalord]

Hi,

GOing to replace the HBV valve 2moro and do a coolant flush. I am going to drain the rad , then put a hose in the header tank and just keep piling water in till it runs clear. When it is running clear im going to make a 50/50 mix and put it in. How many litres does it take?

Matt

[Marks DTM Calib]

Just under 10 from empty but, the block wont be empty so put most of the antifreeze in first (5 litres) with just a few litres of water added to ensure once fully mxed you get the correct ratio.

[omegalord]

Just under 10 from empty but, the block wont be empty so put most of the antifreeze in first (5 litres) with just a few litres of water added to ensure once fully mxed you get the correct ratio.

Right,

So put 5ltr in then say 3ltr in , then do i run the engine with cap off and heaters on max for 5 mins. Then do i check and fill up to correct amount then run for 5 more mins?

Then when i have finished i should have only put 5ltr of af and 5ltr of water?

matt

[ians]

Matt,

It works like this.

(Approximately) the engine takes 10 litres.   But as you will find when you drain it out, you'll only get about 5 litres out (you'll get more if you change water pump but I'm assuming you're not doing that).   So you need to repeatedly flush until to all intents the 5 litres left in the block is alomst pure water.  Then add your 5 litre can of neat antifreeze.  So you then have 5 litres antifreeze + 5 litres of water = 50%.  Its slightly less than 5 litres that remains in the block so after you've added the can of AF, top up as necessary with clean water.

Premixing 50/50 is fine for any future topups (if you lose a bit of coolant for any reason) but not for the initial fill as you will end up with closer to 25% AF.

Cheers
Ian

[omegalord]

Hi Ian,

So to get the coolant flushed out , i can just put a hose from my tap in the header tank and keep pounding water after water in till it is running out clear cant i?

Then i add the 5ltr of neat antifreeze. Then do i need to put heaters on full or do i just go for a quick run around then come back and check coolant level?

Matt

[omegalord]

Just another thought , where the hell can i drain all the old orangey burnt water as it stains  

[ians]

I have tended to refill with water and run with heaters on for 10 mins.  Let cool a bit. Drain. Refill and repeat until satisfied.

The level marked on the tank is the cold level remember so some patience needed

[Dazzler]

I have tended to refill with water and run with heaters on for 10 mins.  Let cool a bit. Drain. Refill and repeat until satisfied.

The level marked on the tank is the cold level remember so some patience needed

I quite agree thats the only way to get fresh water into the block

[Andy B]

All you ever wanted to know about a coolant change is here

[duggs]

Took me AGES to get all the old fluid out of my V6.....even when it ran dry. Plonked the rad hose back on...ran the engine for 30 secs...took the hose off again...and tons more water/coolant flooded out. Did the same 3 or 4 times before truely..the system was empty.

[omegalord]

Surely if i was pumping water through with a hose , then eventually all the crap would come out?

Matt

[Darth Loo-knee]

When you have undone the screw at the bottom of the Rad to let out the water, you are not draining ALL the water out of the Cooling System. When the thermostat is shut there is water left in side the engine. Like said earlier if you took out the water pump most of the water would then come out, but you aren't going to do that are ya???
So by you draining the Rad you are only taking about half the water out. So like someone said earlier it takes ages to actually dilute the flusher you have put in. I must have filled with clear water run it then dropped the water 20-25 times over two weeks to get the water clean before i put in the anti freeze... But the difference now is that the temperature gauge reads 92 1/2 ...

[ians]

Surely if i was pumping water through with a hose , then eventually all the crap would come out?

Matt

Not if that water was just running straight through the rad to the drain.  Your flush needs to get in everywhere, inc heater matrix to flush it out.

.. and I wouldn't be running my engine for 2-3 minutes with little or no coolant in it..

[Kevin Wood]

Best way is probably to do as Hotel21 has suggested in the past and run the engine with the hose pouring into the header tank and the radiator drain plug open. That way the hose is replenishing the water, it's getting pumped round the whole system (bar the rad, which probably drains anyway) and the engine never empties.

I'll probably give it a go at the weekend.

Kevin

[omegalord]

When you have undone the screw at the bottom of the Rad to let out the water, you are not draining ALL the water out of the Cooling System. When the thermostat is shut there is water left in side the engine. Like said earlier if you took out the water pump most of the water would then come out, but you aren't going to do that are ya???
So by you draining the Rad you are only taking about half the water out. So like someone said earlier it takes ages to actually dilute the flusher you have put in. I must have filled with clear water run it then dropped the water 20-25 times over two weeks to get the water clean before i put in the anti freeze... But the difference now is that the temperature gauge reads 92 1/2 ...

I understand the process i was just asking if its ok to just keep pouring water in until it runs clear. If it will work better by having the rad plug open and running the engine whilst the hose is constantly pounding water in the header tank then ill do that until it runs clear.

Matt