Oil pressure release valve?

[dougal]

Does anyone know about them? I noticed the other day that when the engine is cold there is plenty of oil pressure, also when the engine is hot and running at mid to high revs there is the usual amount of pressure, but as soon as the revs drop below 2-2.5k rpm the pressure just drops to nothing! From what I have read either my oil pressure release valve has got stuck open or the sender is knackered. What I was wondering is......do you normally have to replace the valve, just clean it or, as some people have suggested, replace the whole pump base?
The oil light doesn't come on either as the bloody bulb doesn't work, something else I've got to fix.

Any advice would be greatly appreciated.

Sorry, should have mentioned it's a 4ltr Pre-Cat engine.

>>> Edited by dougal on Tuesday 11th December 14:14

[dougal]

Thanks Steve, haven't dared touch it since I noticed. I don't think it is engine wear as it was absolutely fine on the way to see a friend (10 miles), but it started on the way back. I always look at the guages regularly during every journey. The oil level is on the button. Surely if the pump was worn it wouldn't have adequate pressure at all, or at least read lower?.....but I am treating it as worst case senario, just in case.
Just bought a copy of your book and read up on the priming of the pump etc. You don't happen to know if the Pressure rel valve is a standard Rover article or have TVR bunged a stronger/weaker spring in to change the pressure?

[dougal]

Thanks for all the help chaps, just thought I'd let you know, checked the release valve and it was fine, so changed the pressure sender and hey presto, loads of pressure on tickover! So it was OK all along. Also changed the oil pressure warning LED as it had stopped working, have the part numbers if anyone needs them.