Coolant Change Procedure Advice

[Neil W]

Had a good search of the forum & decided to ask the idiots guide to Coolant Change in one block.
As a newbie this is filling me with the joys of oh my goodness.

From all the vast experience here I plan to carry the coolant change as follows – if wrong please add in.
My Stag has the original set up with no extras / mods & had the engine rebuilt 1500 miles ago & has in it already Comma XStream done by the last owner.

1. Engine Cold – open bonnet
2. Remove Expansion Tank cap.
Put heater control to ON ie Hot settling
3. Remove lower radiator hose & drain contents to bucket (dispose of)
4. Remove Radiator brass top screw & top hose - drain a bit more.
5. Flush Radiator out
6. Remove Block plugs under manifold 2 off & drain water – give a poke inside to make sure clear.
7. Fit radiator bottom & top hose.
8. Fill radiator with mixture 5 litres distilled water & 5 litres Comma XStream G40 mix. When water comes out block plugs refit, then fill Radiator to full. Fit brass plug.
9. Fill expansion tank to bracket level.
10.Run Engine watching temp gauge for 20 mins to expel all air – refit expansion bottle cap.
11.Done .

Neil

[wilf]

Make sure the heater water control valve is "On" before you drain and refill.

[Neil W]

Make sure the heater water control valve is "On" before you drain and refill.

Good point forgot about that - cheers

[nib]

I also remove the thermostat and flush through with garden hose. Whilst the thermostat is out it's a good idea to put it in a saucepan and check it's opening fully when boiling, if you have a spare thermostat it's good to compare the two when doing this test.
Mark

[DJT]

Neil,

I've said this many times on here, but I would change your step #3. Just removing the bottom hose results in a very wet sleeve and lots of spilt anti-freeze. Instead, remove the brass filler plug and insert a length of clear hose down the side tank until it reaches the bottom. Syphon the coolant out into bucket until it stops flowing. Now remove the bottom hose and spillage will be minimal, or none. Doubters refer to the act of syphoning being hazardous due to the risk of ingesting anti-freeze. That is why I suggest using a clear hose. You can then see where the coolant is in the hose and stop sucking well before it reaches your lips (Oooer missus ). I've been doing this for years and not swallowed any coolant yet.

[milothedog]

Had a good search of the forum & decided to ask the idiots guide to Coolant Change in one block.
As a newbie this is filling me with the joys of oh my goodness.

From all the vast experience here I plan to carry the coolant change as follows – if wrong please add in.
My Stag has the original set up with no extras / mods & had the engine rebuilt 1500 miles ago & has in it already Comma XStream done by the last owner.

1. Engine Cold – open bonnet
2. Remove Expansion Tank cap.
Put heater control to ON ie Hot settling
3. Remove lower radiator hose & drain contents to bucket (dispose of)
4. Remove Radiator brass top screw & top hose - drain a bit more.
5. Flush Radiator out
6. Remove Block plugs under manifold 2 off & drain water – give a poke inside to make sure clear.
7. Fit radiator bottom & top hose.
8. Fill radiator with mixture 5 litres distilled water & 5 litres Comma XStream G40 mix. When water comes out block plugs refit, then fill Radiator to full. Fit brass plug.
9. Fill expansion tank to bracket level.
10.Run Engine watching temp gauge for 20 mins to expel all air – refit expansion bottle cap.
11.Done .

Neil

8. refill with OAT coolant and forget about it for 5 years

[DJT]

8. refill with OAT coolant and forget about it for 5 years

You'll be mentioning HTs next..........

[milothedog]

You'll be mentioning HTs next..........

Mines been running on it for over 7 years now

[Neil W]

Neil,

I've said this many times on here, but I would change your step #3. Just removing the bottom hose results in a very wet sleeve and lots of spilt anti-freeze. Instead, remove the brass filler plug and insert a length of clear hose down the side tank until it reaches the bottom. Syphon the coolant out into bucket until it stops flowing. Now remove the bottom hose and spillage will be minimal, or none. Doubters refer to the act of syphoning being hazardous due to the risk of ingesting anti-freeze. That is why I suggest using a clear hose. You can then see where the coolant is in the hose and stop sucking well before it reaches your lips (Oooer missus ). I've been doing this for years and not swallowed any coolant yet.

I didn't know there was a space down the inside of the radiator so syphoning the anti freeze is less messy - may get the Misses on the job as from Mark's suggestion of testing the thermostat I may need to go near the cooker which is not my domain - know I get excited everytime I play with the Stag, but don't think she will be impressed at the 'syphoning' and I lied last time something was put in her ...

Not sure about OAT - no many unknowns on compatibilty / seal etc but good luck to milothedog.

Had a bad experience on my TR7 with the cyl head threads for the thermostat housing when I flushed that out - cooling is fine at present so will leave that component alone for now - if it had been a cast iron head it would have been out.

Neil

[Jeff]

Use a suction hand pump if you don't want to suck with your mouth, only a few quid.

I have OAT in mine, not a problem since the rebuild.

Jeff.

[KOY 23]

Is that because it hasn't moved?

[wilf]

I don't see how you can adequately flush a Stag cooling system with the 'stat in place?

When I did mine, I reverse flushed it through the 'stat housing - some compressed air through there brought much more silt out of the disconnected bottom hose.

I can understand the fear of shearing a bolt tho' - was very ginger with mine, but luckily had no issues there. Put them back with copperslip.

[Ian F]

Neil

No-one has mentioned raising the near side front wheel of the car when you refill it, it helps reduce the risk of air locks.

Ian

[Jeff]

Is that because it hasn't moved?

MOT today!

[milothedog]

MOT today!

Out working with my Son today but keep me posted