Replaced the rad today for an alloy one. The heat management seems much better now. I've yet to cut the old rad open, but about 1/3rd of the external matrix was clogged with oil/ dirt from when the oil coolers (now replaced) leaked, so I doubt that helped.

Patient closed up- new thermostat (old one opened a bit slower), water pump ( old bearing was on its way out) and new Ect sensor ( intermotor, not Lucas). Shd improve heat management, is the plan, and keep some heat off the fuel rail when the engine has been turned off.

Nope, but I've ordered one on ebay. Lrcat doesn't list the long bolts, but the other front cover bolts are all listed as 5/16 UNC, so I think my hypothesis is correct

I'm thinking the short bolts are M8 x 1.25 and the long are 5/16" with 18 tpi, at any rate the thread pitch seems to be fractionally larger on the long bolts vs the short. The short bolts/ holes take dies/ taps of M8 x1.25, but the M8 die doesn't work on the long bolts, and nor does a 5/16-24. I know LR are good at mixing metric/ imperial, and I suppose the longer bolts go into the (imperial) block. I only really need to know for thread cleaning purposes

Roger that...Airtex only, right?

ok, a lot of wiggling and it came loose, so looking good.

The pump has a metal impeller (good) and is pretty solid, but with some surface pitting, as if someone has taken a hammer and punch to the surface, v odd. I'm in two minds about replacing it. The bearing runs "dry" i think would be the expression ie as it goes round i can hear metal on metal in the bearing, but no grease, there's a little play in the bearing but not much. How do the bearings of a new water pump get lubricated - are they pre-packed/ sealed with a marine grease?

Actually, can anyone confirm that the bolt holes on the water pump housing are threaded? Perhaps they're not and I just need to pull it nice and straight. I think there's probably just crud holding it on

As is traditional for me (don't start), a routine disassembly becomes more complicated as a result of a sheared bolt. Removing the water pump for inspection, it was the centre top bolt - with the thread exposed at the back, so likely corroded in. The good news, the bolt sheared just below the hex, so maximum bolt length to remove the stud. The bad news, the bolts are threaded for their entire length, so I can't get the pump off due to this one sheared bolt.

The bolt seems to be an M8 flanged 30mm. Lrcat talks about M8 but 25mm - I doubt it matters greatly, but I just wanted to be sure I had the right spec, anyone know?

I'm hoping that when I get the water pump off I find that the impeller is on its way out, which will make me feel better. There's definitely some play in the bearing, so that's good.

do you have any dashcam footage? Not sure if I'm more interested in hearing the engine seize up, or the choice words from your wife about "this f***ing car, it's always going wrong etc etc"

Thanks Gents. Leaky injectors ? Possibly, although it held pressure today for the half hour that I was watching it after I turned off- still haven't discounted the injectors though. Richard, as you suggested I'm now looking at the "chop it out" options, if you know of any filter set up that works, let me know... I was thinking of just cutting the steel line between tank and filter, and then putting a rubber hose over that and running forward to a male fitting (thread to be confirmed, possibly the filter is M16x1.5) to link up to the OE filter? However, then the male nut doesn't turn when I want it to (although the front pipe is perfectly serviceable), not my area of expertise, however. Is there a good website of fuel pipe repair fittings/ options? Am googling as we speak

Pressure test today was 26 with the FPR under vacuum, and 34 when not (pulled the pipe off the inlet manifold this time, rather than the FPR ). Clearly the pressure from the pump's not the greatest, but the regulator seems ready to cap it at 26 psi on occasions, so I'll keep my eye on that. Meanwhile the temp at the rail rises from the ambient temp of the fuel to about 70 degrees within 10-15 minutes of shut down, but there's no corresponding increase in the rail pressure - it stays steady.
The restart issue seems to occur when the rail is 60 degrees plus, since I'm not going to be able to get my fuel filter off any time soon then I'm going to put some reflective tape on the fuel rail as a heat shield, which may reduce the heating up on the fuel rail. I'm also going to change the thermostat which might help the cooling system manage the engine temp better. I had an over-heat the first weekend I got the car, which was mainly due to the PO having placed a second thermostat (which was clogged up) in the housing used for the 4.0 ie the front nose-piece on the inlet manifold. But I never replaced the lower thermostat, so possibly that's not as free flowing as it should be. If i'm bored I'll pop the water pump off too, to see how it's looking.

Did you cross check the part numbers with lrcat?

Mad-as,
Clowns to the left of me, jokers to the right - either way it's a car crash. Labour lost the plot a few years back, Conservatives more recently - oh for the days when parties aimed to capture the electoral middle ground

After a retest, pressure at the fuel rail is a constant 31 psi, but now there's no pressure response from either taking the vacuum pipe off the regulator, or pinching the return feed (with a brake clamp) Sadly I still haven't been able to get the filter off, the 3-way Irwin vise grip pliers were a bit of a waste of time. I'm starting to resign myself to getting new tank-end fuel pipes, but haven't tried the non-flame heat source yet, as I don't really have anything suitable lying around

Not sure I followed about the O2 sensors, but equally I'm not sure they do too much in the first few seconds. Have you got a heater voltage?

What fuel pressure do you see at start up? Those Laser spark plugs lights are a quick and easy way to get comfortable on the spark, may be worth pulling some plugs to see what you can see.
Is your idle air setup looking OK?

Sounds like you shd do the decent thing, old shep, and buy it back

Mad-as, Thanks for having the patience to got through the whole thing. I'm trying to work through things using data as much as possible, without changing parts at random. So the only thing that's changed on the air side is IACV steps - everything else passed muster (with the exception of the IAT sensor, but perhaps that's due to wiring resistance). Once the new 02 sensors (exhaust needed changing, and old sensors were rusted in) settled I haven't needed to worry about them. As you say, then there's fuel - the fuel filter's held me up for a few weeks now, the restart issue's not bad enough for me to have gone nuclear on the fuel filter, mainly cos I don't want to lose the fuel line if i don't have to, and the fuel pump is last on my list because it falls into PITA-to-fix territory, relative to the others, at least. Sooner or later I'll declare war on the fuel filter - probably when I next get close to E - and I think I'll do another pressure test on the fuel rail as I know the data sounds low (although the GEMS data for rail pressure and FPR pressure seems hard to validate definitively) - but i really don't have any power issues with the engine. It sounds better now than it has ever done - although still probably runs rich, and hence I opted to Redex the injectors, in case they were dirty. I've had the car a year and a half now, and so don't know how it sounded/felt 10 yrs ago, but I do have the 4.0L V8 in my Defender to go by and it compares quite well (but richer as noted). Sadly I don't have a boat to tow over hills :o)

If you fancy heading to Twickenham, I'll be happy to and I'm around most of next week, although Gilbert D taught me all I know, so he is the last word in P38s :o)

It's not impossible that there's some obstruction, and I still haven't managed to get the fuel filter off, that would tell me a lot about the state of the fuel system I suspect. I froze the filter/ fuel pipe coupling, that didn't work, and next I have some flare spanner-like vise grips coming. Unfortunately the whole connection is too narrow for me to get a crows foot on otherwise it could have been a quick job - but thus far I am in no hurry to strong arm it and end up ripping the end off the filter cannister. In the background I stuck some Redex in the tank today in the hope that that might help clean the injectors, rather than strip things down.

I have compressed air, is there a procedure for clearing the fuel lines/ rail ? or just blow....return to the rear, and feed toward the rail...