Quick question about changing oil spring...

[volospian]

If I change the oil pressure relief spring, do I need to drain the oil first? Does oil come out of the hole for the spring when I undo the nut, or is it simply a case of undoing the nut, swapping the springs over, and doing it back up again?

[Nefarious]

I asked this question of my mechanic chat, and he said that the spring acts on a ball valve, so it should be possible to change without draining the oil. If oil does come out then the relief valve itself is failing.

Important to underline that you must get ALL of the old spring out, as it's very easy for a little end to break off (especially on an already failed spring), potentially causing all manner of problems (well, primarily the valve not working!!)

[volospian]

Cheers,

I don't think the spring is too bad, there is still oil pressure, but I'll check it against the replacement... how would you get any missing bits... magnetic screwdriver or something, I presume?

[Nefarious]

Not really sure, not having done the job myself. It looks like there's reasonable visibility, so a check with a strong light (and mirror if necessary). Poke around with a screwdriver and maybe tweezers.

Sorry, that's about as far as my knowledge goes I'm afraid...

[Tanguero]

Access at least for visibility was prety tight on mine. When I changed the plunger (not a ball bearing!) I ended up taking the entire valve body with feed tube off. Only a 5 min job but I am fairly sure you would need to drain the oil first.

I have only replaced the spring during an oil change so I don't know if it can be done without - I suspect it could be very messy finding out!

[Sir Beerah]

The spring can be changed without draining the oil. The oil pressure relief valve is in an oil gallery and requires pump pressure to maintain oil in the gallery, therefore some residual oil will come out when you undo the nut but it will not drain the sump. As stated in an earlier reply ensure you remove all of the spring if it is broken (you will still have oil pressure with a broken spring, just not as high as it should be).