15 replies to this topic

[Brookesy]

Hi all

Mini is a 1989 mini 30.

So this weeks problem is this. Last week Radiator started leaking water through the radiator cap. Spurting onto the underside of the boot/inside engine bay e.t.c. I ordered a new 15lb rad cap from minispares and kept the coolant level topped up till it arrived today. Fitted the new cap and thought all was well.

However although it has stopped leaking coolant it is still leaking steam which is condensing on the bonnet still and still making a mess! Engine temp is ok but can see the steam when stopped at lights e.t.c.

All the hoses seem ok with no other leaks. Maybe the radiator fitting that the cap fits too is out of shape?

Any advice would be great. Thanks Mike

[Cooperman]

Sounds like a damaged cap seat, but that's a bit unusual. Is it overfull with coolant? If it is, then it will push coolant out as it warms until it reaches a 'full when hot' level.

[Brookesy]

Well at the moment it is sat flush with the metal 'filament' inside the radiator. Which i think may even be a bit under?

[Cooperman]

Well at the moment it is sat flush with the metal 'filament' inside the radiator. Which i think may even be a bit under?

It shouldn't steam then once it's hot.

[zef]

Coolant system blockage or sounds like the coolant system might be getting pressurised. Could be a head gasket.

[Brookesy]

So bleed the rad first if still not fixed then check head gasket? well other way round..

[icklemini]

seen a few of these recently:

- Water level should be flush with the filament... the 15lb cap shouldnt be venting..., seen a radiator last week with a tiny crack in it...

Before going too crazy and taking everything apart - get the cooling system pressure tested to see if the system is holding pressure, and if not: trace the leak...

[bmcecosse]

You sure the cap has the right stem length to seal down inside the radiator ?

[zef]

I'd bleed the system first, yes.
Remove the cap, turn the heater to hot and top up the system while running the engine (watch your fingers). Leave the cap off until the system gets up to temp, the thermostat should then be open. That should shift any air.

[Brookesy]

Cheers for the advice. Will try and shift any air there may be and if it still vents on the way to work ill ge tthe pressure tested

Thankyou once again. blooming cars fix one and out pops another!

[Brookesy]

You sure the cap has the right stem length to seal down inside the radiator ?

It seems a touch short butits the same as the old one and the right one for the year of the car. Old one worked fine till itt started spurting:(

[adam_93rio]

Are you sure the radiator hasnt been changed at some point. The stem shouldn't be short

[Brookesy]

So ive searched throughly and there is definatly no leaks. After doing a bit of research im thinking maybe a head gasket problem. Going to check oil tommorow for water as the amount im loosing from the rad cant just be from steam..:/

[Brookesy]

Oil is also fine. Nice and dark. Time to visit le garage I suppose...

[Ethel]

Squeeze the top hose to see if it pressurises before it warms up. It's a fair indicator of a duffed headgasket. Sometimes you see mist in the radiator header too.