Evan's waterless coolant is best.......no water = no corrosion and no blocked radiator from corrosion material circulation...bit expensive and a bit of faff pre-cleaning etc but long term worth it...studs that stick into water jacket will no longer corrode etc.
There are available BSF/Whitworth socket sets, but mostly open ended and ring spanners can be used. Auto-jumble and rallies are where you caan find stalls with such things and old spanners BSF/WHITWORTH.

Detergent less oil only recommended because old engine likely to have oil ways lined with crud which would clean off and get to places it should not and so do damage. Bear in mind there is no fine oil filter on the 7 unless someone has done a modification to fit a modern spin on can filter....very worthwhile.
You need to read up on oils to get the full picture. Oil chemistry has come a long way since the days of A7. 20W/50 is pretty thick and power sapping (Power? A7?) My V6 3 lit Scimitar was recommended as 20W/50 in the early 80s but as one of our, research engineer, Scim club members said "it is now only really ok for your clapped out lawn mower"!
I am about to do an oil change after running in timing gears and will be using 0W/40 but I also use Synionic Anti Friction Metal Treatment (AFMT) added to my oil (started life called Prolong in USA and proven by SINTEF lab and MIRAS). Have used it for last 45,000 in the eng, gbox and axle. I will be using fully synthetic oil....but bear in mind the Scim also has a modern filter.
Happy reading.

Dennis

Location: West Devon

Hi Andrew,
Not long an RP owner myself.
Simon is right there seem to be as many conflicting pearls of wisdom as there are owners!
I remember when Castrol R was available from my local garage but now even bog standard oil has become a specialist item.
Which Oil by Richard Michell is a good read if you want to find out more about oil, it’s properties and use in classic cars.
It is important to use non-detergent oil as Dennis N points out. I use 30 in the engine 40 in the gearbox and 140 in the axle.
We could arrange to meet up for a pint with the RPs around Brandesburton or Lund if you fancy a run out sometime.
Cheers, Roger

Location: Up the road from Hull

The above comments reinforce the need for basic introductory guide to Seven owners, free of pet complicating notions (but mentioning steering arms!).

The book “Which Oil” seems to be about the only one of the type available now. I dont think the author is an oil development engineer or chemist, more a moderately clued enthusiast. His oil change recommendation are absurdly conservative, esp for warm Oz. He is obsessed with static viscosities and time stability of, but completely ignores the question of instant viscosity under high shear of non synthetic multigrades. (The possible case for 30 in racing engines, and probably the real reason for use in Porsches)

Has anyone clearly established that current oils in an old jet fed engine with cleaned sump lead to trouble? I have seen many laid up moderns from the 60s with heavy sump sludge and presumably elsewhere but no problems, despite many tiny oil holes in rockers, rapid oil flow etc. It seems a waste to chase about and pay a premium for an SA or SB oil of 1940s spec of the sort with which engines wore out in 30,000 miles, when API SG or better is available at the nearest supermarket.

As mentioned a problem with Sevens is that there is so much info available it needs a considerable degree of expertise to sort the wheat from the chaff so is only confusing to the present day newcomer.

The comment that thick oils sap power is very true. My car on straight 50 in cold Wellington southerlies could not attain top gear! 20W50 is a long way from 20 and notably thick at normal temps. The static viscosity charts in the book interesting (but when comparing watch for changing scales). The author overlooks that fact that noise and leakage often factors in choice of oil, not wear.

Pressure loadings in a stock Seven very modest cf moderns

Location: Auckland, NZ