Changing engine oil cooler pipes?

I need to replace my engine oil cooler pipes to/from oil filter - oil cooler as they are just starting to weap on the flexi hose.

ESR3440 & ESR3438

Do I need to buy new O rings ESR2237 and will I need 4?

It all looks quite tight doing this job. Has anybody done this? Any tips or advice?

Cheers Simon

Firstly..the pipe nuts tend to seize on the cooler because of the dissimilar metals (Ally to steel) and can be a pain to undo. Forget WD40, use Plus Gas and gently try and work them free otherwise the threads on the cooler stubs can rip and strip with half the thread left in the nut-result..new cooler. Yes, there is one "O" ring on each end of the hose assembly. The connection to the filter end is accessible, best to remove the grille and slam panel for access to the cooler connections. The other hose to the front cover is easily accessible, but a word of advice..when you come to refit the hose to the front cover,don't go mad tightening it otherwise you will crack the threaded boss....result...new cover at £200+

dont forget the o rings, i have and theres oil all over the place!! lol!!!

if you take the rad out then you can see the cooler quite well, this will mean draining the coolant but if your taking rad out you can clean it inside and out!!