sierrafery
Well-Known Member
the heater setting is completely irrelevant on the D2 as there's constant flow through the matrix regardless of the setting, it's visible in those schemes pasted by Brian few post ago
Kadonkadonk1
Member
I appreciate people trying to help as I know nothing and the only info that I can get is from the internet. Hence why I'm here.
But I get easily confused by the amount of advice I get which as to which is right and which is wrong so I end up getting into a pickle.
All I need is to get all air out of the system and make sure it's completely full... the correct way lol
But I get easily confused by the amount of advice I get which as to which is right and which is wrong so I end up getting into a pickle.
All I need is to get all air out of the system and make sure it's completely full... the correct way lol
Colthebrummie
Well-Known Member
Admittedly, I don't know much about the coolant system on a D2 but I always have the heater set to hot when I empty and refill the system. Maybe my old fashioned ways are irrevelant with modern engines but I've never had any problems with changing coolant or needing to bleed the system. I suppose I've just been lucky.
Col
brian47
Well-Known Member
There would seem to be some confusion here, particularly around the volumes of coolant and methods of refillng.
All the information is given in RAVE (which I realise is of no use to you because you're using crApple products and a .pdf of the Td5 Disco workshop manual is very hard to find. If anyone can help here).
The volumes quoted are 13 litres for a complete fill from dry or 8 litres for a drain, flush and refill. In your case you're doing about 6 litres because you've been unable to drain the system using the correct drain plug on the bottom coolant rail and some coolant has been left in the system below the point where you were able to remove the old coolant.
As @sierrafery has said, the heater matrix is permanently in the circuit, there is no method of stopping the coolant from circulating through the matrix. Any "switching off" of the heater is only done by flaps blocking the airflow through the matrix and not by altering the coolant flow through it.
So, having drained as much of the old coolant as you can, the recommended method of refilling the system is as follows:-
Refill
If by flushing with plain water you've diluted or washed out the remaining coolant, the new coolant should be a very strong mix or even neat and allow for mixing to take place once everything is circulating.
Assuming everything is washed out, that would leave 5 litres of now plain water, in your case about 7 litres remaining in galleries and other "undrainable" places.
In order to preserve the 50/50 mix, in a 13 litre system you're going to need 6 1/2 litres of concentrate and the same amount of water.
So, by replacing the water you drained out after the last flush, you're going to need to refill with neat anti-freeze concentrate.
If 8 litres were drained out and the system flushed completely, then the refill should be 6 1/2 litres of concentrate and 1 1/2 litres of water and the system allowed to mix the coolant itself while in use.
If you were just doing a quick "drain and refill" without flushing, then the coolant mix for the refill can be at 50/50; 4 litres of concentrate to 4 litres of water.
After driving for a few miles to allow this mixing, I would advise checking the strength of the coolant with a suitable hydrometer.
All the information is given in RAVE (which I realise is of no use to you because you're using crApple products and a .pdf of the Td5 Disco workshop manual is very hard to find. If anyone can help here).
The volumes quoted are 13 litres for a complete fill from dry or 8 litres for a drain, flush and refill. In your case you're doing about 6 litres because you've been unable to drain the system using the correct drain plug on the bottom coolant rail and some coolant has been left in the system below the point where you were able to remove the old coolant.
As @sierrafery has said, the heater matrix is permanently in the circuit, there is no method of stopping the coolant from circulating through the matrix. Any "switching off" of the heater is only done by flaps blocking the airflow through the matrix and not by altering the coolant flow through it.
So, having drained as much of the old coolant as you can, the recommended method of refilling the system is as follows:-
Refill
- Flush system with water under low pressure. Do not use water under high pressure as it could damage the radiator.
- Fit new sealing washer to drain plug. Fit and tighten drain plug in coolant pump feed pipe.
- Fit access cover to underbelly panel.
- Prepare coolant to required concentration.
- Remove bleed screw from top hose.
- Unclip the bleed hose from the battery box. (I don't know why this step should be required)
- Unclip the expansion tank from its mounting bracket, remove the expansion tank cap and raise the expansion tank vertically 10 cm (4 in). Retain the tank in this position.
- Slowly fill the system through the coolant expansion tank until a steady flow of coolant is emitted from the bleed hole.
- Fit the bleed screw, then, with the expansion tank still raised, continue filling the system until coolant level reaches the cold level mark on expansion tank.
- Fit expansion tank filler cap, fit the expansion tank to its mounting bracket and clip the bleed hose to the battery box.
- Start and run engine until normal operating temperature is reached, and check for leaks.
- Switch off engine and allow to cool.
- Check for leaks and top-up coolant to the cold level mark on expansion tank.
If by flushing with plain water you've diluted or washed out the remaining coolant, the new coolant should be a very strong mix or even neat and allow for mixing to take place once everything is circulating.
Assuming everything is washed out, that would leave 5 litres of now plain water, in your case about 7 litres remaining in galleries and other "undrainable" places.
In order to preserve the 50/50 mix, in a 13 litre system you're going to need 6 1/2 litres of concentrate and the same amount of water.
So, by replacing the water you drained out after the last flush, you're going to need to refill with neat anti-freeze concentrate.
If 8 litres were drained out and the system flushed completely, then the refill should be 6 1/2 litres of concentrate and 1 1/2 litres of water and the system allowed to mix the coolant itself while in use.
If you were just doing a quick "drain and refill" without flushing, then the coolant mix for the refill can be at 50/50; 4 litres of concentrate to 4 litres of water.
After driving for a few miles to allow this mixing, I would advise checking the strength of the coolant with a suitable hydrometer.
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sierrafery
Well-Known Member
That ''keep the revs above 1500rpm untill no bubbles come out near the bleed screw" is additional to RAVE based on how the system is built and from my own and other's experience who tried that based on this advice it's a good move cos there's no other way to bleed air which eventually is trapped in the bypass circuit which is closed by the thermostat's mechanical bypass valve which opens only above 1500rpm(provided the pump and the valve work as they should)
