Hi Guys,

 

I was always under the impression the radiator on a 300zx was a closed system , if pressure builds up the rad cap allows it to bleed off ?

 

My car is fitted with a Koyo rad and this has a tube coming from an oulet near the rad car that is open to air , is this normal ? this would be a an open system allowing water vapor to escape?

 

Thanks,

 

Adam

I thought that tube goes to the expansion tank located under the nearside wheel arch?

Read all these posts mate.

https://www.300zx.co.uk/forums/showthread.php?171587-radiator-over-flow-bottle-delete

The tube goes into a header tank or catch tank..any coolant that lifts the cap and drains into the tank is then siphoned back into the rad as it cools as a vacuum is formed by the cooling water in the Rad. This type of system is kept topped up by keeping the correct level in the catch tank and not the rad.:)

You probably don't want that. As the radiator cap opens to let off pressure, when it cools down, as it was vented to atmosphere you will simply be losing coolant.

Read all these posts mate.

https://www.300zx.co.uk/forums/showthread.php?171587-radiator-over-flow-bottle-delete

 

Cheers mate, just read all these. Mark built my car for rustysills , so that would explain the lack of over flow bottle .

 

My car has always used water since I built it up last winter . Nothing mental just it needs topping up every three weeks of daily driving. This would explain the usage . No compression issues and did a block test cos I thought the hg was on its way out .

 

Going to fit a catch bottle and see if and see if anything condenses out