Boiling coolant?

[Luke52]

Went down to the bike shop today to get a few bits and pieces, and upon returning to the car, I noticed a strange burbling noise when I got inside. Thinking something had broken and I was dumping all my oil, I popped the hood and jumped out to see what was going on.

No oil catastrophe, however the burbling sound was definitely coming from the cooling system, and seemed more audible on the passenger side of the engine bay, near the overflow bottle. I double, triple, and quadruple checked that I wasn't parked over a drain or something.

Got back in the car, temp guage was normal, just about 1/3 of the way up. Went through the menu on the dash, coolant temp was at 101 degrees.

Eventually after about 10 minutes of looking around, checking radiator hoses and coolant levels and all that, the burbling noise quietened down. I drove back to the shops near home, keeping an eye on the temp guage, which remained normal. When I pulled up at the shops, the burbling noise had returned again. Drove home with the coolant temp on the display, and it varied between 100-110 degrees.

I can't say I've noticed this noise before today, either.

Any ideas? Should I get the cooling system checked out, or could this just be a case of the last person not getting the coolant concentration right, leaving too much water?

Thanks in advance.

[HamaTime™]

Water pump

[impulsive]

check your coolant cap, when its cool obviously... its probably starting to destroy itself

[Luke52]

Alright, something f**king weird is going on here.

Firstly, I opened the coolant cap. It's fine, however the coolant should be a red colour, am I right? It looks as though there is only water in it, no coolant at all, which would explain the boiling yesterday...I only bought the car a few months back, so it came like this.

Secondly, I checked the coolant level in the overflow bottle again. When I pulled out the yellow dipstick, it was showing as empty.

Thirdly, I let the engine idle for a while. After half an hour of idling, the thermo fans still hadn't switched on, and the level in the overflow was still showing as nil.

Oh, not to mention the fact that my heater doesn't work either. Just blows out cold air, even if the temp knob on the dash is turned all the way to hot.

[Benboy]

If the coolant is low the temperature gauage probably won't give you an accurate and timely warning. Pays to do an inspection of your car at least once a week. Check oil level, water, brake fluid, auto trans (if fitted), front and rear head an tail lights, stop and turning indicators, warning device (horn), wipers, wheels, tyre pressures etc. Such checks don't take long but in doing them you will have some peacce of mind in the knowledge that your car is not only roadworthy but also unlikely to suffer failure due to a lack of general maintenance and care. If you coolant level was low and what reained was boiling you can expect to have caused some damage, possibly to the head gasket.

[Luke52]

Coolant level was fine when I checked yesterday, and was normal last week. Checked it when I changed my oil.

Just this morning I opened the coolant cap, then checked the overflow, and it was showing nothing.

[impulsive]

fill it up then. prob pay to do a coolant flush too...

[Luke52]

Yeah, I'm thinking I'll get the coolant replaced, and the whole cooling system pressure-tested after the holidays. Just for peace of mind.

[Luke52]

Topped it up with some water and drove it today, keeping an eye on the coolant temp.

Wandered anywhere betwwen 85-95 degrees, and I didn't hear the boiling/burbling sound at all. Interesting indeed.

I'm still gonna get the coolant flushed and the system tested, though.

[dirtslinger]

did your heaters work again after you topped up the levels ?

[db_notso]

+1 coolant pressure test and probably replace the radiator cap as its not holding pressure or low coolant percentage or leaks if boiling coolant

[Luke52]

did your heaters work again after you topped up the levels ?

Good question. I knew there was something I missed!

I'll check it out tomorrow.

[Luke52]

Who would have thought finding a radiator cap for a Commodore would be so hard?

I need a screw-type. The only screw-type I have listed at work is a 140kpa, I need a 120. The only 120 listed is a bottle-type, which won't fit as the base is too big.

Looked up what I thought was the correct one in the CPC book, as the picture looked the same from the top, and it was a 120kpa. We didn't have it, but I went down to Autobarn. They had it, but it was a bottle-type...the picture didn't show that.

I'm going to try R&E and Bursons on Wednesday. Failing that, off to Holden I go...

[RiCeY]

Pressurizing the cooling system is what raises the boiling point of the coolant and stops the water boiling. So if its boiling Id say theres a leak somewhere such as the cap as already mentioned.

When the engines warm make sure both radiator hoses are hot so you know the thermostat is opening and coolant is flowing through the engine correctly.

[ozzypole]

Sorry to hijack this thread, but how do you display the coolant temp in the digital display?

[Luke52]

Pressurizing the cooling system is what raises the boiling point of the coolant and stops the water boiling. So if its boiling Id say theres a leak somewhere such as the cap as already mentioned.

When the engines warm make sure both radiator hoses are hot so you know the thermostat is opening and coolant is flowing through the engine correctly.

I checked that on the first day it happened, both hoses were hot.

Yesterday I decided to check out the thermo fan issue, too. One of the thermo relays is the same as the high beam relay, so I swapped them around, and the high beams still worked fine. Relay seems fine, but I think I'll just replace them for the hell of it. A cooling system isn't something something I want to go "She'll be right" about...

Sorry to hijack this thread, but how do you display the coolant temp in the digital display?

Put the key in the ignition, hold down the mode and set buttons, and turn your key to the "on" position. The screen will show the GM serial number or something like that. Then press the mode button to browse through the various information.

[Luke52]

Checked the other day, heater works again.

Funnily enough, it seems as though this was a one-off event. Drove to Ocean Grove and back again yesterday, no worries.

I will still buy a new cap from Holden, however. Preventative maintenance more than anything, just for peace of mind...

Thanks for the help and advice, ladies and gentlemen.

[RiCeY]

Probably an air lock that cleared itself.

[jetboy]

"Sticky thermostat" ............... Im putting a fiver on it .

[Luke52]

Certainly hope it's not the thermostat. Yay for removing the intake manifold to access it...

[FnomnaVZ]

Are the thermo fans working now? I think they kick in around 115 deg on the VZ. Could take a while to get there - put the digital display on.

[Luke52]

115 degrees? Are you serious?

Jeez. I was freaking out today because they weren't kicking in. Took it over to the boys across the road from work, they had the scan tool on it, and the temp was showing at 108 degrees, and still no fan. I thought that was fairly high, and they should be turning on by then...

[RiCeY]

VE V6 kicks in at around 109 degrees from memory... VZ Im not sure

[greenacc]

Do the fans work when you switch AC on ?

[ozzypole]

'Put the key in the ignition, hold down the mode and set buttons, and turn your key to the "on" position. The screen will show the GM serial number or something like that. Then press the mode button to browse through the various information.' Luke52, Thanx for this helpful info.