Radiator Coolant Level VY V6

[wortus]

My radiator coolant is just visable in the radiator when the cap is removed on a cold engine. I refilled it to the bottom of the cap, drove it for a week and the level is back to below the cap/just visable in the radiator under the cap.
Should I be looking at replacing the cap or is this normal? I would have thought it should always be full up to the bottom of the cap?

[VYMAD]

Mine is generally full to the bottom of the cap, Check the overflow to make sure it's where it should be and not drawing coolant out to compensate a leak. Yeah mine is always level with the overflow hose on the side.

[wortus]

Mine is generally full to the bottom of the cap, Check the overflow to make sure it's where it should be and not drawing coolant out to compensate a leak. Yeah mine is always level with the overflow hose on the side.

Thanks. The overflow is always full. I've filled the radiator and will see if the level in the overflow goes up. I'll grab a new cap tomorrow. The one on it is a CPC do you know if they are the OEM and the same as sold by Holden as a genuine part?

[Sean880]

Wortus

The coolant level when COLD in my vehicle normally sits about 5-7 mm below the the bottom rubber of the fitted the radiator cap. (When I checked today that was where it was also). When the coolant is just warm(not hot) the fluid level is right up to the cap rubber of course and there is still some significant system pressure releasing as you loosen the cap gently.

Even though I have a very low km car I replaced the original radiator cap (from when the car was new) this year with a new one from Holden. I still have the original cap and it is "CPC". (It shows very little sign of any deterioration though).

[wortus]

Thanks Sean. I think I will pick up a new one today either a genuine one or a CPC. Was the new one from Holden also CPC? My cap looks fine and I'd say it is stil the original one as are all the hoses and everything else in the engine bay are still original from new. (except the battery which only died abut 6 months ago).

[wortus]

Are the caps on a VY V6 the same as a VX? The CPC catalogue says they are different and the same as a V8 so I am thinking that may be a mistake?

[VYMAD]

Wortus, my original said 135 kpa system, which is what I replaced it with when I bought my new one.
EDIT: I just checked my old one which was the factory cap and it is CPC, the same type that I replaced it with from Super cheap. And definately 135 kpa.

[Sean880]

Thanks Sean. I think I will pick up a new one today either a genuine one or a CPC. Was the new one from Holden also CPC? My cap looks fine and I'd say it is stil the original one as are all the hoses and everything else in the engine bay are still original from new. (except the battery which only died abut 6 months ago).

Yes the new cap purchased from Holden Parts was also "CPC" and the same spec as the originally fitted item.
Cheers

[wortus]

Wortus, my original said 135 kpa system, which is what I replaced it with when I bought my new one.
EDIT: I just checked my old one which was the factory cap and it is CPC, the same type that I replaced it with from Super cheap. And definately 135 kpa.

The one I got is a 522-20 135kPa it looks identical to the one already on the car so it shoudl be OK. The CPC catalogue must be wrong as it says 575/100 which is a plastic cap for a surge tank.

I'll stick this new one on later today, check the system for air and see how it goes. Thanks for your help.

[VYMAD]

Yeah no worries, Wortus, I, though would buy a CPC 135 KPA, then you can't go wrong, I take it you don't have a supercharger, in case that might make a difference?

[wortus]

Yeah no worries, Wortus, I, though would buy a CPC 135 KPA, then you can't go wrong, I take it you don't have a supercharger, in case that might make a difference?

I just checked the overflow bottle and the coolant has been sucked back into the radiator, couldn't take the cap off as it's still under a bit of pressure so it looks like the cap may be OK? I'll see how it goes over th enext few days and if the coolant is still disapearing then I guess it's leaking somewhere?

[WAGON MAN]

Wortus,

Did the new radiator cap resolve your issue?

[wortus]

Wortus,

Did the new radiator cap resolve your issue?

Hi Wagon Man yes I have checked the coolant level once after fitting the new cap and when cold the coolant was just under the bottom of the cap. I'll check it again is a week or so just to make sure.
One thing I noticed is the new cap's return valve is plastic where as the original one was brass.
Also the CPC parts catalogue for a VY V6 is wrong. The cap it lists is for the V8.