We replaced the seals, anti-rusted the door interiors and replaced any self-tapping screws with stainless.

Due to rust, we had to cut out and reweld the RH rear floor, plus one front outrigger and an inner sill part related to the RH floor.

Refitting was fairly straightforward although I had to do it slightly differently than Aston suggest. There are 28 trim clips holding the screen in, and these were also replaced (some had totally rusted away!). Below you can see before and after pics.

Is the gauge ok? -tested against a known source of pressure at 20 and 70 psi and it looks accurate, but the car seems to operate the oil pressure relief at about 60psi instead of the expected 80+ ??

Investigated oil pressure relief valve and it had only 1 0.05" shim instead of the minimum of 0.18" that the manual states. Added a shim the bring the shims to 0.19" app. and reassembled. Oil pressure now limits at about 85psi @ 3000rpm so that's that one fixed then. However the low pressure at idle remains...

The oil has now been replaced with hard-to-find 20-50 multigrade, which helped very slightly.

20/6/2002

It seems that the low idle pressure is likely due to the mains, which were not replaced when the car was last rebuilt. I suspect that doing it won't be fun (depends what you call fun I suppose).

1/7/2003

The Aston now has a rebuilt bottom end. This was done in situ and was NOT so easy, though it was possible at least (Aston don't say it is!). We had to unbolt the rack and the front end pipework, exhausts, steering column shaft, gearbox engine steady, etc. in order to get the engine JUST high enough to get the sump off. It was also necessary to unbolt the windage tray before we could manoeuvre the sump off. Changing the main bearing shells was no different to any other engine, EXCEPT that 4 of the shells (the intermediates, which are different to the other shells) were marked as -010 size according to the manual, but, as I found out the hard way, were in fact standard. I've never seen such a thing before and can only suggest that anyone planning to take an Aston apart measures the shell thickness, rather than just reading the shell markings as I did. According to Aston dealers, this sort of thing is "quite common" with Astons! (good grief!)

The reason for the low oil pressure was rather evident as soon as the sump came off: one of the light alloy screw-in plugs that seal the oil galleries in the crank webs had come right out and been smashed into 1/4" square lumps in the bottom of the sump by the crank. These plugs are notorious for loosening and they were all checked and the missing one replaced and  loctited/punched in position. The amazing thing for me was that the bearings were not badly affected (I checked them all of course). The 2 big ends on the crank throw concerned (the last) showed <slight> signs of overheating, but not too bad, with no scoring or "wiping", and all the main bearings had normal wear, pretty much to their limit, which we expected, but no scoring or low oil pressure-related damage etc. We replaced all the mains and the 2 big ends on the throw which lost a plug - the other big ends looked as good as new, as did the crank, and with shells at upward of £30 each, we felt that the £350 plus it cost for the mains plus 2 big ends was enough!

I am frankly amazed that the car could have been driven around for some <months> like that and have not severely damaged it's bottom end, which says a lot for Astons legendary mechanical strength. I can only assume that the very large oil pump passes so much oil around that even with almost nil oil pressure on that crank throw, the bearings could survive a while.