Help needed after my first coolant flushing...

[yohn222]

Hi Guys

I bought my first Commodore last week and, so far, am pleased I did. It's a 1998 VT Acclaim (the manual says Calais on it too) - 3.8 litre V6.

However, the coolant looked a little rusty so I asked the ex NRMA mechanic I'd paid to inspect it before I hand over the cash whether this was something I could do myself, he said I could and said do the following:

Remove the top radiator hose from the radiator. Turn on the car so the old coolant starts being pumped out (being careful not to get any on the electrics) of the hose and stick a garden hose in the radiator on slow/medium pressure. Wait until the water starts coming out clear (after 5/10 mins - it took nearer 15-20). Then, let it cool down and start the engine for a minute, this time without the hose, so the remaining clear water gets pumped out. Then fill it back up with a 50/50 coolant mixture putting the coolant in first. Also he said stick a hose in (what seems to be) the resevoir tank to clean it out.

I did all of the above, the olnly difference being I thought I'd remove to bottom radiator hose from the radiator too to flush out any sediment in the bottom of the radiator.

I then let it cool again and put in the coolant. It took about 5 litres of coolant and that was it. In the handbook it says the coolant capacity is 12 litres. I presume that as no water actually came out the second time I ran the engine (this time without the hose and for 2 or 3 minutes in fact, watching the temp gauge the whole time), the reason it only took 5 litres of coolant is because 7(ish) litres of water were still in it from when I was flushing it?

I have ran the engine a couple more times and it lets me put a little more in each time but not much.

My next question is what is the black tank with the yellow lid for, is it actually a resevoir or an overflow? I ask because, in the manual it says in the event of over heating, top up the radiator and the other tank - why both?

Also, it seems as though this tank is over-full. It's difficult to tell from the dipstick as it's hard to read but it seems as though I've way too much in there? Is this a problem and if so, how should should I fix it? Furthermore, I just drove the car for about 25 mins then took the radiator cap off to see if it'd take anymore coolant but, as I turned the radiator cap into the stop position and let the pressure out, a load of coolant water (about 1/2 litre) came out of somewhere around by the coolant tank/overflow thing (well that's where it seemed to come from, didn't seem to be from the radiator cap). Any idea what was happening here?

When I took it for a drive the temperature much higher than the 1/4 mark so (hopefully) that's a good thing.

I'm sorry for going into so much detail but I thought the more I gave you the easier it'd be for someone more knowledgeable than myself to work out what's going on. Any help/advice would be much appreciated!

[accentstencil]

Hello and welcome. The tank you mention is the overflow tank, it needs to be at a level between the arrows on the dipstick when cold.
When you flushed the radiator did you turn the heater dial to hot so the heater core would be flushed too?
Usually, after flushing and refilling you need to bleed the system. This is done by slowly undoing the bleeder valve on the thermostat housing ( the thermostat housing is where the top radiator hose connects to the engine). When the engine is at normal operating temperature and with the engine running, slowly undo the screw just enough to let the air out. When no more air and only coolant escapes, it is bled. You may need to do it few times.
Your car is either an Acclaim or a Calais, not both. If it has climate control it will be a Calais, if not then it's an Acclaim. Good luck with it.

[yohn222]

Hi. Thanks for the advice. I did have the heater dial set to hot, yes. If my overflow tank is too full, what's the best way of letting water out. Presumably just letting some out of the radiator won't do it. Speaking of which could anyone tell me where the radiator draining valve thing is exactly, I couldn't see it?

Also, am I right in thinking then that as the engine needs to take in more coolant or get rid of some as it has too much it either takes it from or gives it too the over flow tank?

That way, if the over flow tank has the correct amount in when cold, that's how you know whether you've put the right amount of coolant in?

I did bleed the car when warm yesterday, will try it when hot and running. Thanks again for the advice, if anyone has the answers to the above it would helo set my mind at ease, have a two hour drive this avo!

[gungazza]

to drain the overfow tank ,just unbolt it ,and it drops down, that way you can clean it out ,then know how much is in there. also in the book it says to remove knock sensors from both sides of block the drain but there are no pics of where thay are

[gungazza]

has enybody got pics of knock sensors

[yohn222]

Right guys...

I just took it out for another drive. Before I started it the coolant in the overflow seemed to be right on the max mark as it did at the end of the drive. This must be good right (as in that it doesn't seem to be way to full anymore)? I can only assume that, as I said above, when I took the radiator cap off last night and coolant seemed to start coming out of the overflow it was getting rid of any excess which has brought it down to the right level - would this sound reasonable?

Also, I just tried bleeding it with the engine running and a nice looking green (Nulon) coolant started coming out straight away.

Could quick questions though. Do you think that the reason I only got 5 litres of coolant in after flushing was because approx 7 litres of clean water that I was using to flush it was still in there (somewhere!)?

If so, I will need to take out approx a litre of what's in there and put in more coolant to bring the mixture up to a 50/50 ratio (as there's only 5 litres of coolant and it has a 12 litre capacity. What is the best way of doing this?

If someone could tell me where the radiator drain valve is that'd help I guess but if not I could just let a litre out of the top radiator pipe. My question then is, when I put the litre back in, should I put it in the coolant overflow or in the radiator? If someone could explain why so I get a better understanding of how it works I'd appreciate that immensely too as I would if someone could take a look at what I've written above posts and let me know if it all seems to make sense.


Many thanks for your time.

[accentstencil]

Right guys...

I just took it out for another drive. Before I started it the coolant in the overflow seemed to be right on the max mark as it did at the end of the drive. This must be good right (as in that it doesn't seem to be way to full anymore)? I can only assume that, as I said above, when I took the radiator cap off last night and coolant seemed to start coming out of the overflow it was getting rid of any excess which has brought it down to the right level - would this sound reasonable?

Also, I just tried bleeding it with the engine running and a nice looking green (Nulon) coolant started coming out straight away.

Could quick questions though. Do you think that the reason I only got 5 litres of coolant in after flushing was because approx 7 litres of clean water that I was using to flush it was still in there (somewhere!)?

If so, I will need to take out approx a litre of what's in there and put in more coolant to bring the mixture up to a 50/50 ratio (as there's only 5 litres of coolant and it has a 12 litre capacity. What is the best way of doing this?

If someone could tell me where the radiator drain valve is that'd help I guess but if not I could just let a litre out of the top radiator pipe. My question then is, when I put the litre back in, should I put it in the coolant overflow or in the radiator? If someone could explain why so I get a better understanding of how it works I'd appreciate that immensely too as I would if someone could take a look at what I've written above posts and let me know if it all seems to make sense.


Many thanks for your time.

There is always going to be some water left in there, so it is best to add 6 litres of staight coolant and then top up with water.

[pablo]

The radiator doen't have a drain ****! the only way to drain it is to remove the bottom hose off it. The maximum I have been able to drain out of my system, without removing the 'knock sensors', is 6 liters. The knock sensers are on each side of the block, about half way along, right above the chassis cross member. You will need to be a contortionist (with small hands) to get the buggers out. After I drained and flushed my system (without removing the sensers)with demineralised water, I removed the top hose off the radiator and poured in the concentrate straight into the top of the engine, when I was just able to get in 6 liters, I replaced the hose and ran the motor to get the coolant mixed, then bled the air, as you have done. You can remove any excess from the overflow tank by inserting a length of plastic hose in it and syphoning it out, tho, I think it will 'self level' after your first drive.

Pablo

That reads 'drain coc_k' above, but the censor thinks it's a naughty word, too naughty for your eyes! LOL

[yohn222]

Thanks for the above advice - sounds like I need to remove at least one hose to drain some of the mixture out before putting in the remaining litre of pure coolant.

In theory, if you're topping it up by pooring coolant in the radiator, is it possible to over-fill it? Am I right in thinking that any excess will go into the over-flow then, if it needs coolant at a later point it takes it from the overflow? I just don't quite get the point of the overflow!

A brief description on how the cooling system works would be most helpful and appreciated!

[BOGANV8]

Read this link and follw the pages at the bottom

HowStuffWorks "How Car Cooling Systems Work"

[vxcalais_01]

If you never removed the bottom hose, i am amazed you got it all in. The way i do it is drop the bottom hose, run a chemical flush through it (cleans scale, rust etc also neutralises left over coolant) then drop it, then all i do is fill it up and keep dropping the hose untill it runs out clean (3-4 times) and flush other areas with a bucket or drink bottle. I dont use a hose due to water restrictions and not necesarry. The filling and emptying technique allows to to get a majority of distilled water in there if thats what you want. When bleeding the car through the bleed screw, the radiator will suck coolant back into it from the overflow reservoir. Good way of telling its working properly. So no need to drop it, unless its really dirty.

Knock sensors are either side of the sump, have a wire clipped to them and screw out with a socket attachment. Only way to fully drain the block. Also pull the hose at the side of the engine near the water pump and flush through there. That gets alot of coolant out from heater and heads etc.

Change the thermostat as well. Best way to fill it up again is to take off top hose from thermostat housing, and fill from there untill coolant/water runs out from the housing. This gets the air out of the block.

THere is an excellent How to in the how too section, with pix and all........

[geraldb]

iv just bought a vt and its only running on water (no coolant) will this wreck it and should i flush and put coolant in it???

[geraldb]

iv just bought a vt and its thermo fan wiring has burnt out so i put it in the electricians and they rigged one up for me. the motor is out of a vy and now i have the engine light coming on why can any one HELP!!

[Gav86]

just so you no, the manual always says calais on it, coz it suits calais as well, ur car is just a plain old acclaim.

[geraldb]

i just done a coolant change and now when i go to bleed it there is NOTHING no air or coolant WHATS HAPPEND WHY HAS THIS HAPPENED??

[accentstencil]

i just done a coolant change and now when i go to bleed it there is NOTHING no air or coolant WHATS HAPPEND WHY HAS THIS HAPPENED??

Are you bleeding it at operating temperature with the engine running?

[geraldb]

i took it for a drive and got it to operating temp and tryed it again and only got a little bit of air should i do it again

[accentstencil]

i took it for a drive and got it to operating temp and tryed it again and only got a little bit of air should i do it again

Coolant should be coming out, are you unscrewing the valve far enough?

[geraldb]

yes coolant coming now but didnt get much air tho how do i know if i need to replace the thomostat

[geraldb]

i done the coolant change cause it only had water in it no coolant and the engine light was coming on and its a little hot on the temp gauge how hot is normal temp??

[accentstencil]

When only coolant and no air comes out it is bled.
The guage should be less than half way at operating temp.

[geraldb]

yes it shows less then half but little bit more then quarter sits right at the bottom of the temp signal is that normal

[accentstencil]

yes it shows less then half but little bit more then quarter sits right at the bottom of the temp signal is that normal

Sounds about right to me.