Radiator Cap

[1998GTS]

Hi Guys.

Can some one tell me what size cap goes on a 98 HSV Series1 GTS,i'm starting to think the one thats on it is wrong.Took it for a run today,got home left it for half a hour,Went and had a look and found alot of water underneath.It's not leaking from anywhere else.

Any help would be great thanks

[304runner]

well pop the bonnet when its running.. It wont jut splash out when its hitting bumps it will hiss or rush out even when the car isnt moving.

[Killr6]

i would be checking the radiator for leaks first. and rad caps are so cheap from autobahn or supershit.

[1998GTS]

Ok.It's flowing back into the overflow bottle from the radiator and leaking(full) from there.Y and should it do that.Never seen this happen before.

[VS_Pete_1]

you need a new cap mate.

[1998GTS]

Thanks mate.But is there a certain size that i have to get.

[Killr6]

dont think there are sizes, they are same cap for a 6 and a 8.

[304runner]

I dont think its the cap at all... Id say its your thermostat thats stuck closed.

If its closed and the water pump is trying to push the water through the engine and up and around the radiator then back in the engine it will hit the stuck thermostat and build up pressure and back itself up into the rad overflow which will then fill and then overflow on itself.

When you head off to buy the cap, you might as well buy a thermostat for $10 and replace it.....

[VS_Pete_1]

OP didn`t say the car was overheating.
If the thermostat was stuck closed it would boil he said he went for a drive and found it a half an hour later after he got home.

[VS_Pete_1]

Thanks mate.But is there a certain size that i have to get.

Take all the details of the car to the shop.
Have a look at the radiator cap and write down what is on the top of the cap something like 135kpa.
Have you got a owners book in the car if so take that aswell.

[1998GTS]

Thanks guys for all your help.

[VS_Pete_1]

So did you get it sorted mate.

[1998GTS]

Going to sort it tomorrow.Thanks

[304runner]

OP didn`t say the car was overheating.
If the thermostat was stuck closed it would boil he said he went for a drive and found it a half an hour later after he got home.

I fail to see how a loose rad cap will cause the over flow bottle to fill.... He can remove the rad cap completely he wanted, it still shouldn't flow through the over flow pipe.

[tezza]

I fail to see how a loose rad cap will cause the over flow bottle to fill.... He can remove the rad cap completely he wanted, it still shouldn't flow through the over flow pipe.

If cap is not doing its job and keeping the system pressurized, coolant temp will get higher and then boil and spew out the overflow.

[304runner]

Always seems to spill out the rad from my experience... A cheap fix either way...