Flushing my coolant

[BiggestNizzy]

I want to flush my coolent this week and seeing as every man and his dog seems to have problems with air in system. whats the best way of doing it ?

[steve_weegie]

I do something like this, assuming you've dropped all the coolant out the system....

refill tank to brim
open engine bay bleed screw until coolant with no air flows out.
refill tank 3/4 full and replace cap.
jack up front left of car only - use jack point near the front wishbone
start engine and run at high idle - i do this by wedging card in between the throttle end stop
wait for engine to warm up to 80ish - at this temp, there will be enough pressure in the system to move air round.
open front bleed screw a bit, and close when coolant with no air is flowing past the bleed screw.
refill tank to 3/4 if needed.
leave engine running until fan comes on.
re-bleed at radiator (2 pairs of latex gloves or asbestos hands are good here...)
drop car and stop engine
remove header cap and leave to cool.

that should get most of the air out. you might need to repeat the jack / radiator bleed after a run to complete the job though.

my 0.01p

[woody]

I want to flush my coolent this week and seeing as every man and his dog seems to have problems with air in system. whats the best way of doing it ?

Bring it round one night Pressure bleeder works well.

[offshorematt]

If all you want to do is generally flush the system, then the following should work (and removes the risk of introducing air into the system)

1) Remove pressure cap and disconnect the return hose from the header tank
2) Route the return hose outboard of the car (piece of flexi tube via the left side vent works)
3) Run the car and watch as the fluid drains out of the system (and all over your drive) but don't let the fluid level drop out of the header tank - each time it gets close, top it back up with clean water from a hosepipe. You're basically draining the system by means of the water pump
4) Drink a beer, read a magazine etc. until the returns are clear water. Will take a wee while
5) Start topping up with some antifreeze in place of water
6) When returns show clean antifreeze, reconnect the return line
7) Run the car for a while to string out the antifreeze through the system

I've done this a few times without problems and while I'm sure its not the optimum way of doing it (not least because it takes a few hours) I can' see any real downsides and it removes the need to bleed anything... Also, I mentioned this to Ali once and he didn't warn me off so I assume it okay...

[Victor Meldrew]

Now dont try this at home...... but it works for me...


Drain all of it by disconnecting the two lower hose fittings on the cant rail pipes and drain coolant. Remove header tank cak, rear bleed screw and front bleed screw... Have a garden hose ready to rinse said coolant off the mono block and into neighbors gravel driveway. go and have cup of coffee. Leave hose running into header tank for a bit.....

Finnish coffee and remember what you were meant to be doing.. head back outside and reconnect the lower hoses. leave hose running into header tank it should be running out of the bleed points at the front now.... leave like this for a bit.... biscuits, never had any biscuits with my coffee... away back inside again... get chased outside because my shoes are dirty and and i might get oil on the chairs... refit front bleed plug and keep the water flowing, it should be coming from the rear vent point by now.

Now.... I should point out that my household water system is running at about 1.8 Bar which is around 22psi ish... the header cap lifts at around 15-18psi... dependent on which one you buy. My hose has an adapter that jams itself nicely into the header tank so I can pressurise the whole system to 15psi from water main pressure.
So its now full of water at operating pressure. crack open the vents front and rear and vent out any water, close off both. Take out the hose/plug. Start the car and run it until the radiator gets hot, approx 86-88 deg with the header tank open to atmospheric. The turn off the engine and vent off the air from each vent point...

Now to get the right anti freeze mix using the above method is a little trial and error... but simple enough. The volume of the coolant system is known.(just not known by me) its not a lot... I start the final fill with about 5 litres of unmixed coolant (or whatever is left)topped up by tapwater from the pressured hose as above... I compare the color with a pre-mixed sample that I made earlier... if its pretty close, that good enough for me.. I know it wont be long before Dan has it in bits again anyway...

[ABZ-Elise]

Also note that the old coolant should be disposed of properly and not over your drive. If anyone clocks you doing that and reports you to sepa, you will be fecked.

[BiggestNizzy]

Also note that the old coolant should be disposed of properly and not over your drive. If anyone clocks you doing that and reports you to sepa, you will be fecked.

what about woody's drive is that ok ? after all it is symington

[Victor Meldrew]

Also note that the old coolant should be disposed of properly and not over your drive. If anyone clocks you doing that and reports you to sepa, you will be fecked.

Thats easy to sort out, just throw some fairy liquid down n the ground before you start.... washing the monoblock mate, if you've got a problem take it up with B&Q.

I know all about SEPA. If you are a company, then yes watch yourself as they are arsseholes but us normal everyday peeps dont interest them one bit.

[Dave]

This thread reminds me I need to change my coolant, can anyone tell me what anti freeze they are using, last time I did it I used the anti freeze that I got from a rover garage, as there's not to many of them around anymore is there an alternate I can get from Halfords etc.

Cheers
Dave

[Rich H]

Best thing to do is replace with the same type you have now.

Orange/Red=OAT
Green/Blue=MEG

They are the industry standard colours, any motorfactors will be able to help.
In theory bad things happen if you mix them, but I dunno how true that is.