Bleeding coolant system RENAULT KANGOO (KC0/1_)

It’s pretty straightforward if you’ve got a bit of patience. Open the bonnet, make sure the engine is cold, and remove the cap from the expansion tank. There’s a bleed screw usually on the coolant hose going to the heater matrix – loosen that slightly. Start filling the coolant very slowly, engine off, and wait til coolant flows steadily out that bleed point, then close it up. Squeeze the coolant hoses gently to help push out air. It’s a bit messy but works every time.​​

Adding to that, once you get the coolant in, leave the expansion tank cap off, and start the engine. Set your heater to max hot (fan on low, doesn’t matter), that way coolant circulates through the heater core. Let the engine warm up to operating temp, keeping an eye on the coolant level and topping up as needed. You’ll see some bubbles rise up, just keep things topped up.​

Another trick — once you’re almost done, go for a gentle drive with the lid off the bottle, but DON’T let it overheat, and watch out for splashing. That tends to ‘burp’ the last bit of air out better than just idling. When back, check for leaks, top up if needed, and cap it up tight.​

If you can’t get all the air out, try squeezing the thicker hoses (wear gloves, can get hot) while the engine runs. It helps pop air bubbles stuck in stubborn spots. Always keep coolant bottle above min to avoid drawing more air in.​

On my Kangoo there were two bleed points — one on the heater pipe, one down at the front near the head. Some models only have one, so feel around the pipes if you’re not sure. Both need to be open when filling—close when coolant flows clean and steady.​

Totally agree. And if the coolant keeps disappearing, check that your cap seals right and there’s no little leaks; air will sneak back in otherwise and you’ll be forever burping it!

Sometimes you get little airlocks in the heater and it blows cold. If that happens, repeat the process, and flex the pipes going to and from the heater matrix again. Fixed it for me last winter.​

If you want to do it properly and avoid burns, only open the cap when the engine is cold. And don’t over-tighten the bleed screws. Plastic gets brittle with age on these!

Honestly, I overfilled mine by a tiny bit the last time, so when it got hot it spat a little. Just keep the level at max, not above, and you should be fine.

If your fan isn’t kicking in, double-check your coolant sensors after this, sometimes air pockets mess up readings and can delay cooling fan operation. Ran into that once!

Mate did this on his diesel Kangoo and said it took two minor top-ups over a week before it stopped dropping — the last air comes out gradually, so don’t stress.

Heard from my neighbor — he uses a cut-off plastic bottle as a makeshift header tank, stuck in the filler neck to help keep coolant high while air is burping out. Not necessary, but helps especially if you’re on a slope or big air pocket.​

If you’ve ever done a VW, this one is trickier but not impossible — take your time, keep those pipes squeezed, works a charm! :)

Swear by the “drive round the block with heater on max” method, always does the trick for the last stubborn air. Good luck mate!