Expansion tank

[ukbiggles]

HI all

If my (Mk2) cooling system was working properly and the car starts from cold with the expansion tank half full (radiator full up to the bottom of the top hose), how high would you expect the coolant to rise in the expansion tank after (say 30 miles)?

Thanks in advance

Gord

[RogerS]

Mine is the same about half full when cold, moves up by approx 10 - 12 mm when warm.

Rog S

[ukbiggles]

Thanks, Rog.

Mine rises quite a bit more than that. But It's a problem I've been trying to solve for quite a while now.

Cheers

Gord

[ukbiggles]

Hi, as a follow up question about the expansion tank, does anyone know what sort of pressure the normal MK2 cooling system should run at? I know we fit 13psi pressure caps, but how much margin is there in the system before the cap lets go?

Cheers

Gord

[DJT]

Mk2 system normally has a 20psi cap. For about 14 years I’ve been using a Volvo header tank which is 20.7psi. No problems encountered.