Stainless Steel header tank

[Daiedmunds]

Hi ive just made a stainless expansion tank and was wondering if there needs to be a pin hole in the cap to release pressure build up, or not, any help would be grateful.

[Daiedmunds]

http://www.flickr.com/photos/55363946@N02/5136645336/

heres a rough pic

[MK999]

It needs a cap that will maintain a constant decent pressure ideally, normally something like 5-10psi.

[Daiedmunds]

i will do a pressure test on it in work, what if it holds more pressure? better or worse

[MK999]

i will do a pressure test on it in work, what if it holds more pressure? better or worse

You can't maintain a steady pressure on a closed system simply with a pinhole in the cap, it should have a proper header tank cap on it ideally. Too much pressure and it will blow coolant lines off.

[Daiedmunds]

You can't maintain a steady pressure on a closed system simply with a pinhole in the cap, it should have a proper header tank cap on it ideally. Too much pressure and it will blow coolant lines off.

ive seen solid yellow plastic caps on the bailey type header, how do they work?

[Daiedmunds]

.
(http://cgi.ebay.co.uk/ws/eBayISAPI.dll?VISuperSize&item=220687538900)

[MK999]

Same way all 'solid' plastic header tank caps work I assume, they have a pressure sensitive valve in them.

[Daiedmunds]

damn i bet the thread ive cut is different to the standard plastic caps iv seen

[Daiedmunds]

http://www.flickr.com/photos/55363946@N02/5136885862/in/photostream/

[Daiedmunds]

anyone know how i can get a relief valve insert for my cap? or how to make one? thanks

[Damo]

Could you not adapt one from a standard cap?

[Daiedmunds]

Could you not adapt one from a standard cap?

i dont know, the stainless one is slightly smaller, so will have to try and adapt it somehow

[Paul]

IIRC Bailey use Golf 4 caps...