22 replies to this topic

[Shiv]

Hi guys,

I'd like to pick at your knowledge if I may - I've got a semi-urgent matter that I'd like to diagnose before tomorrow:




This morning I stumbled upon a minor coolant leak by accident.

Car drove fine. But then whilst crawling through some traffic tonight, I heard a weird noise coming from behind the air-vents. Sounded as if there was a mini water fountain behind there. That description rings a bell to me. I'm sure I've read about it either here or on OzLib...

Coolant level is a bit lower than expected but still OK. I've topped it up.

However that drip has become a bit more rapid since the AM.

Any ideas what the problem could be? I need to do a bit of driving tomorrow and wondering if I need to put all that off...




Any thoughts/suggestions would be massively appreciated!!

[RX25SE]

The loss of coolant has allowed air into the cooling system. You can hear the air bubbles as they pass through the heater core under the dash.

You really need to have the system pressure tested to find the leak, repair the leak and refill and bleed the system. Better still to flush out the existing coolant while your are at it as different types of coolant cannot be mixed.


In the mean time, fill the system cold as best you can including the overflow. Top up from the the overflow when hot.

[Shiv]

The loss of coolant has allowed air into the cooling system. You can hear the air bubbles as they pass through the heater core under the dash.

You really need to have the system pressure tested to find the leak, repair the leak and refill and bleed the system. Better still to flush out the existing coolant while your are at it as different types of coolant cannot be mixed.


In the mean time, fill the system cold as best you can including the overflow. Top up from the the overflow when hot.

Ah ok, so that noise is air bubbles passing through the heater core.

The heater core is the big **** under the passenger side dash isn't it?

I forgot to mention when the air con was off tonight, there was warm air coming through the footwell. Air con works fine. Heater works fine. But warm air coming through the footwell even when everything is off.

[RX25SE]

Heater core is usually behind the center of the dash and the A/C evap. under/behind the glovebox.

Warm air may be just heat soak or a slightly out of adjustment air flap in the heater box. I wouldn't worry.


I would worry about the coolant leak.

[Shiv]

Righto thanks for that Jase!

Will get that looked at tomorrow....hopefully nothing too $$$.

[Shaz]

Can you see it dripping or leaking anywhere Shiverus?
I know it's silly, but is your radiator cap on properly?
Any hoses on the engine been fiddled with or replaced?

Cheers,
Shazza.

[Nicko_]

Would it possibly be the heater core gone??

[Shiv]

Can you see it dripping or leaking anywhere Shiverus?
I know it's silly, but is your radiator cap on properly?
Any hoses on the engine been fiddled with or replaced?

Cheers,
Shazza.

Nah Shazza, just underneath the car I can see a slow constant leak.

Plans cancelled tomorrow....going to give it to the mechanic and get it check out ASAP. Was rather hoping to take it for a drive this weekend...

[Nicko_]

Nah Shazza, just underneath the car I can see a slow constant leak.

Dont worry then. If it was the heater core you would have coolant underneath your carpet.



Cheers

[Jimbo]

I wouldnt be worried about excess warm air in the cabin.

Its when you have climate control on 32 degrees and you can only feel cool air when you should be panicking!

[AussieTemplar]

My radiator carked it too, but the leak was obvious. There was a massive crack along the resoivoir.. Coolant just sprayed out of it. Took me 3 months to actually get a new radiator (thanks ahaz!) and put it in. No problems since. Good luck with it Shiv.

[Morgan]

Was rather hoping to take it for a drive this weekend...

You coming to the drive ins on sat?

[tmh983]

I have just been through something very similar, turned out it was a crack in the top tank of the radiator, but only weeping very slightly and the coolant was evaporating before it had a chance to drip. It wasn't until the weep turned into a general torrent that I actually found where it was leaking. But yeah, i had the same heater noise as you when the coolent level dropped.

[Shiv]

I wouldnt be worried about excess warm air in the cabin.

Its when you have climate control on 32 degrees and you can only feel cool air when you should be panicking!

Yeh then I'd be very worried!

You coming to the drive ins on sat?

Nah Morgs, I got a party that night to go too. Wish I could do both, haha...


Anyway car is at the shop now Hopefully nothing too serious.

[B4TT]

Best of luck brew!

I have the waterfall feature installed in my heater core at the moment, no leaks just I CBF bleeding the cooling system any more.

Hoping for you it is something simple that needs replacing/tightening

[bobbyjimmy]

You coming to the drive ins on sat?

Sounds like you where hoping for some make out action back in the 60's...

[Shiv]

Just went up and picked the car,

All fixed

They did a pressure test and found the problem was a pin hole sized puncture to one of the radiator hoses. Another hose was no good so replaced that as well. Flushed out the coolants etc. Also replaced the thermostat as a safeguard.

Only thing is in the 500m driving back from the garage, it was still making that water fountain noise behind the vents. A hell of a lot too! I'm assuming this has got something to do with the system just being flushed out or am I having a heater core problem like what Josh and a few others mentioned?

[Alex]

Try bleeding it properly.


Search for instructions here.

Nose up, heater on max, rad cap off, clamp line to overflow

run a few heat cycles through it (waiting for fans to kick in and out)

coolant will oscillate.


after fans have switched off, top up coolant in radiator (handy to have someone revving to 3k rpm to help) and put rad cap on.

clamp off overflow. let it cool. top up overflow as required.

see if that works.

[Start]

Yup sounds like they didn't bleed the system correctly = waterfall sound.

beaten.

[Shiv]

Cheers Alex, I might give that a shot tomorrow morning if it doesn't subside tonight.

Maybe a silly question but do I have to use 100% exactly the same coolant as what my mechanics would have chucked into it?