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Is this easy to do on the 9N1? its 1.2s need to remove and replace with new G12+ ...is there a bleed or valve available on the radiator or do I have to use the old remove the lower rad pipe ect? the reason i ask is because I know polos get air in their system so if there is a bleed air valve also will the job easier, I just got this car so wanted to make sure first

Thanks

Yes there is a bleed valve on the radiator and yes it is quicker to release the bottom hose to get rid of the old coolant.

Thanks-should this be done with a warm (thermostat open) or old engine?

Ta

You will need the car running to do this properely. I wouldn't be doing it with the car fully warmed up. Squeeze the hoses to get any potential air lock moving and top up as required . Make sure you tightened the bleed screw up once completed.

thanks so a rough step by step is...

1. run car until moderately warm
2. Remove lower hose (open expansion tank cap)
3. Let old coolant spill out
4. Top up with new Coolant/water mix
5. check for any air locks by squeezing on pipes prior to connecting back to Rad.
6. Use bleed valve to remove any air lock once system is connected back

Now do I run steps 3 and 4 together, i,e drain and top up at the same time? (bit like a brake fluid change?)

akz786 wrote:thanks so a rough step by step is...

1. run car until moderately warm
2. Remove lower hose (open expansion tank cap)
3. Let old coolant spill out
4. Top up with new Coolant/water mix
5. check for any air locks by squeezing on pipes prior to connecting back to Rad.
6. Use bleed valve to remove any air lock once system is connected back

Now do I run steps 3 and 4 together, i,e drain and top up at the same time? (bit like a brake fluid change?)

Hello AKZ786

1. TAKE BOTTOM HOSE OFF AND DRAIN SYSTEM DON'T HAVE THE CAR RUNNING AT THIS STAGE.
2. REPLACE BOTTOM HOSE TO ORIGINAL POSTION AND TIGHTENED HOSECLIP AS REQUIRED.
3. START TO FILL THE WATER UP IN CAR WITH REQUIRED OR RECOMMENDED MIX ANTIFREEZE+WATER.
4. SQUEEZE THE HOSES AT THE BOTTOM TO DISPLACE ANY AIR TRAPPED AND TOP UP AS REQUIRED.
5. REPLACE EXPANSION CAP ON WATER BOTTLE.
6. TURN ENGINE ON AND LET CAR RUN TILL THE NEEDLE STARTS TO MOVE ABIT AND USE THE BLEED SCREW TO ALLOW ANY AIR TO ESCAPE BY OPENING UP AND TIGHTENING PERIODICALLY.
7. TOP UP WATER AS REQUIRED TO MAX LINE.
8. SQUEEZE THE HOSES ONCE MORE AND TIGHTENED THE BLEED SCREW.
9. MAKE SURE EVERYTHING IS TIGHTENED UP AND THAT THERE ARE NO LEAKS AND MAKE SURE NO SPANNERS LEFT IN ENGINE BAY.
10. TURN OFF THE ENGINE AND THATS YOU DONE.

Thank you so much!

Need to do this on my GT soon too, I assume it's ok to let the old coolant just leak out of the bottom when you take the lower pipe off??

GR33NIE wrote:I assume it's ok to let the old coolant just leak out of the bottom when you take the lower pipe off??

I hope by that you mean that you simply wont allow the coolant to drain onto the floor and let Mother Nature clear it up?

Coolant, like brake-fluid and engine oil, needs disposing off crorrectly.

ihpj wrote:

GR33NIE wrote:I assume it's ok to let the old coolant just leak out of the bottom when you take the lower pipe off??

I hope by that you mean that you simply wont allow the coolant to drain onto the floor and let Mother Nature clear it up?

Coolant, like brake-fluid and engine oil, needs disposing off crorrectly.

Well that's why I was asking ''Let old coolant spill out'' Spill out where exactly on the floor? I didn't think that was the best option...