Thread: expansion cap o ring

Someone posted recently the generic part no. for a nitrile O-ring for the P38 is AS568-214.

Is the D2 cap the same?

Originally Posted by p38arover

Someone posted recently the generic part no. for a nitrile O-ring for the P38 is AS568-214.

Is the D2 cap the same?

[ame=http://www.ebay.com.au/itm/LAND-ROVER-Discovery-2-Range-Rover-L322-RANGE-ROVER-P38-EXPANSION-TANK-CAP-/251583227105?pt=AU_Car_Parts_Accessories&hash=item 3a938764e1&_uhb=1]Land Rover Discovery 2 Range Rover L322 Range Rover P38 Expansion Tank CAP | eBay[/ame]

According to that.. probably...

Was thinking to visit my local bearing mob to see if they have something that'd fit, would someone please have a picture they could show me of exactly where the ring is supposed to sit so I can fit an alternative to the right spot?
Actually never mind, roverlords lovely pictures blown up I think I can see it

There are 2 O-rings on the P38A and D2 cap.

lol. god knows where my other one ended up then! I spose I'll find out when the water backs up behind it and busts out of the radiator :/
ah no, there it is; though mine looks square not round


thanks for your help/ We'll survive a short drive to the bearing mob minus one o ring wont we?

Michelle, disregard that part no. I found the post and it was referring to using an o-ring under the cap. See http://www.aulro.com/afvb/p38a-range...ap-repair.html

Sorry about that.

Nevertheless, if you take that cap into a bearing shop, they should be able to source an O-ring of the correct size.

i think you'll be right for a short drive.

just be aware that a non properly sealed and tightened cap will cause overheating/coolant loss...the gist is that the cap must keep 1.4 bar in the system to rise the boiling point of the coolant to 123*C otherwise if it's warm outside the operating temp of the engine gets close to 95*C when at ambient pressure the water starts to create small bubbles wich will pressurise the system and as there's no sealing he cap's valve will not open... and so on

in a nutshell: for a well working cooling system the tank's cap MUST be well sealed and well tightened.... summer time it's not uncommon to get coolant temps around 100*C when at ambient pressure the coolant will actually start boiling

Michelle, your cap looks as though it is broken

If you check out the picture of the new one you can see it has an o ring on the very end, yours appears to be missing the plastic on the end that would hold it in place.

Personally, for the cost of a new cap and the potential damage it could cause if it fails, I would be replacing the complete unit.

Well spotted Sidders. Michelle's images hadn't displayed on my iPad. Even if they had, I'm not sure I'd have seen that.