240 General: 244GL in New Zealand with a few problems

[fuel]

Hey guys!

This is my first old RWD Volvo, quite the tank it is! I've owned a 850 Turbo sedan previous and I really liked it.

I saw this '76 244GL 2.1 fuel injected 4spd manual for sale and I just knew I had to have it, problems and all. At the price I paid and given the age I didn't expect it to be problem free, so am now just trying to go through each problem one by one to sort them out.

Firstly, and perhaps the most important is that the oil pressure warning lamp is always illuminated when the ignition is on position two - the engine *sounds* fine with no knocking and I don't think the oil pressure is low, but one thing I have noticed is sometimes the light will flicker or glow faintly when the engine revs increase above 3000rpm (am estimating, the tachometer doesn't work). I figure it could be a number of issues, the most simplest being a faulty oil pressure sensor, stuck open oil pressure relief valve, or the engine really does have poor oil pressure due to worn oil pump etc. Can the oil pressure relief valve be accessed externally or does the sump or oil pump require to be removed in order to do so?

Secondly, as above the tachometer doesn't work - the ignition oil appears to have all wires correctly connected to it, is this a common problem and is it easy to fix?

Third, my brake lamps do not illuminate - I have replaced the bulbs but they still don't go - am guessing it's the brake pedal switch but I've heard the rear wiring loom can have troubles, and if this is the case where is the most likely place to first look?

Fourth, the blower fan doesn't work - common issue or perhaps just a fuse?

Fifth, odometer stopped at 301,000kms and hasn't registered travel since 2007 - another common fault?

Sixth, the windscreen wipers don't self park - is it likely to be the park switch in the wiper motor or could it be something else? (like a Peugeot 406 I once had, turned out to be the intermittent wiper relay at fault after replacing the wiper motor and finding the wipers still didn't self park).

Oh and lastly, one of the rear doors does not appear to open from the inside - yes I have checked the child safety lock and it's not activated, the internal door handle still pulls and has a little resistance (as opposed to not being able to pull the handle at all with child safety lock on), and I can see it actuating something on the door catch yet the door still doesn't open! Thoughts?

Thanks guys!