Vitesse radiator cap

[Robin]

Just bought a replacement radiator cap for my vitesse mk 2 but I've just noticed it's marked as 7 lb not 13 lb as per the manual. Does it matter?

[Guest]

Hello Robin.

 

Yes it does.

 

I have a Mk2 and the correct cap is rated at 13lb.

 

Regards.

 

Richard.

[Pete Lewis]

The pressure is deveopled in heating and raises the boiling point of water above the normal 100c

the higher the pressure the higher the boiling point

 

dont ask by how much , someone else will find that out.

 

the engine will run fine with eg. No cap but if she gets hot you need the reserve

there, s also some physics about the pressure aiding the coolant taking on the heat from the castings

surface contact

 

same as you eeh ahh ooh picking up a hot potatoe, rather than grab the swine with a iron grip and

really go pink

 

So stick to the spec , its there for a good reason and with rad caps there is also a number of different sprung seal heights to suit differing filler neck depths and single or double cap seals for semi sealed systems

 

pete,

[Robin]

Thanks both - just ordered a 13lb cap!

[Freyasgrandad]

I had a similar issue when buying a new cap for my Vitesse Mk2, my local motor factor had it listed as 7 psi as well. Happily he also had a suitable 13psi cap, when I read my workshop manual it does appear that some GT6 and Mk1 Vitesse did run 7psi caps.

 

As an aside, would you believe that someone could or would even be bothered to bodge a rad cap? Because they did on mine, the return valve was missing and the centre spindle had been soldered to the cap.