Thanks Gd - you can be sure I'll post pics of the bores once I remove the heads. (I wish the couriers would hurry up with those sockets!)

I managed to get one of the cam followers out earlier (LH bank, #2 from the front) and it was beautiful. The bottom was mirror-smooth. I couldn't see my face in it, but I could very, very clearly see the weave of my T-shirt reflected. So that's one thing that matches a 75k speedo/mileage figure.

But your "wondering" about the engine or the oil is precisely the question I was asking myself. Is it really as original as a 75k speedo reading would suggest, or has something else taken place - or is it 75k oil?? I have a service record which strongly suggests a reasonable level of servicing, but who really knows what that means.

I will obviously be replacing all the seals and gaskets on the way 'back out' from this point. I have new plugs and leads on order, or already here.

Camshaft. I have a deal of faith in Turners' experience and track record as being a gold-standard supplier so I'm about 80-90% decided to go for their camshaft upgrade. I'm sure I haven't driven the car long enough to have a properly informed opinion about the engine performance - but I can see it increasing my knowledge and experience, while not emptying my wallet.

My daughter's just said she'd like to come home from Uni and get some intensive post-Covid driving experience in before going for a text.

The Yeti's too .new and the insurance would be annoying; the Defender's just not a learner's car; so I'd better get a move on with the P38!

I think you've found just about THE best place for P38 advice and assistance in the whole www. Welcome.

My P38 is my 3rd Range Rover - 2 'classics' before this - but it's my 1st P38 and I'm pretty much a newbie too. Mechanically it seems pretty simple, electronics might be another issue, but the whole package is a lovely machine. As Gd says, at least you shouldn't have too much rust to worry about.

Well...... It strikes me that it must often be frustrating to offer good, hard-won and experienced advice to people.......only to have them ignore it!

Pearls among swine, Gd. Pearls among swine.....!

The whole front of the engine was actually pretty grotty. Oil and muck, so I though I'd just prefer to 'do it properly'.

Even underneath the sump was very oily, so I'm thinking that it was leaking somewhere - either the gasket, or one of the oil cooler pipes.

Sump removed ....

More strange non-factory marker pen....

Underneath the engine looked darker than I might have expected

when I took the sump of my 300Tdi, after 23 years and 220,000 miles it looked astonishingly (to me) shiny and clean. I could look straight up under the pistons and see 'clean' metal. This seems a lot darker. I thought the detergents in modern oils were supposed to help keep things fresher? I know the history of my Defender from when it had 65k on the clock, and was about 7 years old. I know I've been pretty religious with the servicing/oil and filter changes, so in that respect I probably shouldn't have been surprised that it looked so clean.

As I was told it, my P38 was a two owner car. Original for about the first 7 years, then the second owner was essentially the same family. It was 'dad's car' then became 'mum's car' until mum felt it easier to use something smaller. Then 'son' said to 'dad' that it ought not to be left sitting around so much, and took it on.

But I do wonder about things. The RH cylinder head has the marker pen writing; the sump has the marker pen; the front of the engine has these stamped marks - are they 'factory'? They don't really look it to me.

Anyway, I think I've reached the bottom of my 'strip down'. Maybe. Camshaft??

I take the point about 'hot' cams being all about the top end. I remember putting a 'fast road' cam, gas flowed head, 1+3/4 SU carb, and competition distributor into a Mini - that was a lot of fun... a lot.

Turner Engineering (who rebuilt my Tdi last year) have a Kent cam on sale. The blurb says this:

_"emphasized text H180 Kent Sports Torque Rover V8 camshaft 4.0 - 4.6 Gems & Mems

Kent Cams H180 'Sports Torque' camshaft has been designed as a straight forward replacement performance cam for the Rover V8 engine and is suitable for both the Gems and Mems (Thor) ignition types.

With a duration of 262º and a valve lift of 11.2mm the H180 camshaft improves low end torque and is capable of increasing peak power by 22bhp, all whilst retaining the use of OE valve springs and maintains stable idle characteristics essential for: everyday use, on or off road, manual or automatic gearbox cars._

_An improved version of the former Kent sports torque H180 v8 camshaft

The new camshaft is produced on an improved 'Chilled Iron' cam blank which gives significantly superior reliability over the original production cams._emphasized text"

I'm 'tempted'. One of the good things about having the P38 as a second car is that I can use it to expand my own mechanical experience (it's doing that already....) so I can 'afford' to have it sitting in the garage while I wait for stuff to come up the road and get fitted.

It's also the case that, even since the beginning of this thread, the car has gone from a 'not quite sure where I'm going with this vehicle' to a 'definite keeper and loving it' sort of thing.

In that respect, even now, an additional £300 for a cam, and £100 for followers isn't 'such' a big deal. If I get the car back together, learn a lot in the process, and then keep it going for the next 5 - 10 years, I'll be delighted.

Thanks very much - appreciate that, particulary the info about the steering shaft. I hadn't really started looking at that yet. I think it was just age making things difficult. The car is off the ground, with no wheels on; and the ignition key was turned to take the steering lock off, so there was absolutely no tension at all in the shaft. I could get the splines to go 'out'; I just couldn't get them to go 'in' and therefore allow enough clearance to pull the UJ off the steering box.

You think that if I refit the longer pump bolts, that go through into the engine block, that this would nip up the seal enough? You're 100% right, it was opening those three longer bolts that gave the leak.

Having said all that, and given the general pattern of iffy maintenance, I am still wondering about going 'all the way' and taking the sump and cover off.

Any thoughts on a warmer cam? I did have a search on here, but couldn't really find anything specific. By the time you buy the cam and followers, its another £400, so not insignificant, but if I don't plan to be back in the neighbourhood for another few years...... ??

Thanks guys - I thought I'd posted a further comment, but I must have missed the button.
Having googled a lot, I wondered the same thing about the old spark plugs. I also read somewhere that they had a 72,000 mile service interval - which could mean they are original on this car, and might help explain they were so difficult to shift.
I now have 8xNGK BCPR6ES on the way.

If I was to do the timing chain etc (If, because the engine has only done 75k) is there any merit at all in a different/upgraded camshaft? I know I'd need to change the followers and pushrods too. Turners have a mildly hotter version available. I don't particulary feel any need for this, just wondering given that I'll be 'there' anyway.

Also read something from Gilbertd about pulling one of the crankshaft bearing caps... but again, at 75k, is this even worth considering??

Hey, I’m back! Strap yourselves in, it’s been a hell of a day....!

It’s been a day when I could have used lots and lots of sweary words , but I’ll spare you that in the interests of brevity.

Started off trying to get the intermediate steering shaft off. I referred very carefully to the WSM – don’t hit anything with a hammer, and push the shaft towards the bulkhead once all the bolts are undone. Ha ha ha ha ha!

I couldn’t figure out what I was doing wrong, but the XXXX thing just wouldn’t shift. Eventually, after just a few gentle taps with a hammer ... I realised that the long set of splines, at the steering box UJ just wasn’t moving enough to give me clearance. So, out came Mr Grinder...!

To be fair to myself, even on the ground, those splines would go no further into the UJ, so cutting it out was the only option. I’m assuming 20 yrs of wear have created a little ridge inside the UJ.

So, manifold out, no great drama, except that the nuts between the manifold and exhaust were a 13mm, a 14mm and a 15mm. How...... entertaining!

Right. Next. Spark plugs. How hard can that be? (Bearing in mind my last 20 years of experience has been on a Defender 300Tdi diesel). On every single plug I had to use a 450mm ½” breaker bar. And, unfortunately, this picture tells its own story (apart from being upside down!).

I did try and use a ‘reverse spiral easy out’ on the broken plug, once I’d dug out all its internals – but to be honest I gave up on that, as I know the heads are coming off anyway, and given how tight all the plugs were in, I thought I was likely to just do more damage.

For those of you more used to spark plugs....

The end of the electrode on the old plugs looks a lot smaller than the new one alongside – have they just eroded over time? Other than that they seem OK to me – pretty consistent, and not fouled.

A set of ‘Champion’ plugs came with the car. Much bigger hex than the old ones - as you can see in the pics. Are these ‘OK’ or should I get something different? Given what’s to follow, the cost of a set of plugs isn’t going to make a lot of difference.....

So, because I’m still waiting for the UK, and the US posties to bring me my new sockets, I couldn’t go any further with the heads, and moved on to the water pump. (I’ll post a separate thread about my new water pump).

The “old” one looks is pretty good nick, I have to say, but I still 100% accept the logic of having a look while I’m here. Though I could probably just clean up the faces and stick this back on.

However (insert lots of sweary words) as soon as I cracked off the first few water pump bolts, I noticed a leak between the front/timing cover and the block. I dived underneath with a torch, just to check that the leak wasn’t simply flowing down that way, but no. The gasket between the timing cover and block is gone. Green line shows the leak – in fact in the orginal uncompressed picture, you can actually see the coolant stream just to the left of the green line.

So, now, having started all of this to try and chase one water leak at the back of the valley gasket, I’m into a tricky head removal, and taking the sump and front cover off.......

Indeed, to get my impact gun onto the crankshaft nut, the radiator will have to come off! At least it’s already empty...

This is where I left it this eve.

I’ve sort of been here before, recently, with the Tdi. So it’s not excessively scary, but I was surprised to see that there were no bolts inside the crankshaft pulley/damper.

I thought there would be some bolts in there, allowing me to attach a tool to lock the pulley while torqueing off the crankshaft nut? (Edit: there are two threaded holes - that's just a rubbish photo)

So, now I’m going to be effectively stripping the engine down to just a short block. It’s certainly giving me good value in the ‘hours in the garage:initial purchase price’ ratio.

If I keep going at this rate, I’ll have the engine out and on the bench by the end of next week.

Having said all of that, it’s probably obvious that I’m not really that bothered. In a perverse way I realise that I’m having to catch up on many, many years of poor or minimal maintenance, and once I’ve done all of this (plus the stuff I’ve already spent many hours on) then I’ll have a car that I’ll be much more confident of mechanically. All the electrickery will be another matter. (but I did unbolt the fusebox today to have a peek underneath, and that at least looks split new.)

And that's about it for now. I might take a day off tomorrow, or pull the radiator out. (FXck! I've only literally just realised that it's not 'just' the radiator that will have to come out on this car, but the oil coolers and AC condenser.... aaargh.)

Please feel free to comment on any of the stuff above – spark plug questions etc.

In addition as I’ll be removing the front cover, what do I do at the same time? Oil pump rotors? Or, given the state of the water pump, and the engine’s 75k miles, are they likely to be pretty good, and I should leave them untouched? Anything else? Radiator looks more or less split new from the inside, and I already have a new serpentine belt and a couple of new jockey pulleys.

Well, I don't know about you guys, but I'm heaving a sigh of relief! We have movement!

With the knowledge that I wouldn't necessarily kill anything by tackling the bolts out of sequence, I went for the ones that my current sockets allow access to - the three middle ones inside the rocker cover; and the middle of the lower line. I just let the impact gun rattle away - loosen, tighten, loosen, tighten etc. They still weren't moving with the gun, but it was doing something, and generating a bit of heat. Then I switched the impact socket onto the long bar and tube handle and I got 4 of them to shift. I've nipped them back up again for now, but they'll come off Ok.

I now need to wait for the slimmer socket to arrive to get access to the ones that are more obstructed by the head casting.

Full of confidence (well, not really) I went to the RHS, removed the liner, and manifold heat shield and loosened the exhaust bolts. Once I knew there were no demons hiding there, I took the same approach with one of the head bolts - on/off/on/off with the gun, then crack it off with the long bar. Got one to just start turning.

I do wonder if something's non-standard here though. It's a 16mm impact socket I'm using, and it's taking a hell of a beating, but it feels just a little too loose for comfort - given the torque involved.

But anyway, I think the long and short of this is that the current dramatic episode is over. I know they will shift, and have worked out a 'process' that will take them off. After all this, I'll defnitely be taking the heads to the machine shop though for a 'once over'

Thanks very much for the info and the moral support!

Thanks Chris - yep, that's precisely the socket I broke last night - 16mm Halfords plug socket. I couldn't use my 3/4 bar as I don't have a 3/4 to 1/2 adaptor. I have one that goes the other way round... I'll fish out the 3/4 bar when the new sockets arrive.

Not sure I'm familiar with grip tight sockets - will have a look at that.

Thanks again guys,
I went round the tool shops here this morning. No sign of a deep 16mm 1/2 drive socket (far less a 5/8)- but someone did wonder if the bolts might be loctited in..
I went to the local Precision machine shop and spoke to a guy there. He suggested a 3/4 drive, 5/8 impact socket. That is a strange beast in the UK. He also suggested (as above) a good solid whack on the head of the bolts with a brass drift - said it could be surprisingly effective.
Came back to work, and have now ordered a 3/4 drive, 5/8 deep socket from the States.. and a set of heavy brass drifts. I have also got a set of cobalt bits (the machine shop guy grimaced when I mentioned that - pretty crude from their perspective I suppose) but one way or another, these heads are coming off.....
While I'm waiting for these new things to arrive, I'll have a go at getting the RHS mudguard, wing liner and manifold off. Perhaps the bolts on the RHS head will be easier, and give me a wee confidence boost.

I'm also stubborn, and I've bought ARP studs... sitting on the shelf.

And I'm near 100% sure the water is from the valley gasket, not the head or the radiator - which looks to be in pretty good condition. I was able to trace pink coolant deposits from the bellhousing, up to the starter, and to the back of the valley gasket. In fact I was just about able to see the actual coolant leaking down at one point. There's a pic above (not brilliant) which shows more dried, pink coolant deposits.

But I still don't 'have to' remove the heads. They were just on the basis of 'seeing as I'm going to be in there, and a slight chance that one of them has a weeping gasket, so it's now a case of stubborn vs sensible...

Sorry guys - hadn't seen the other replies coming in.

Totally agree - walk away and calm down is a good idea. And yes, I was using the gun anti-clockwise 😎! Haven't tried freezer spray, but there could be a first time.

Further question though, on the point about removing some, and drilling out the remainder - presumably by removing the bolts 'randomly' it's more likely the head would warp and need attention (though they are obviously stone cold.)

Thanks Richard, yeah - just leaving them be and fixing the coolant leak is definitely an option. I thougt I'd included that in my little rant, but I must have edited it out without realising.

Because of the big oily stains on the front of the heads, I do wonder if perhaps there might be some leak there, but as far as I'm aware there are no mechanical signs of it. Runs fine as far as I can tell, no unusual smoke, pulls well, and I think the only coolant it's using is the stuff that's leaking. If I do this, I'll clean that gunk off and then keep an eye on it. At least this way I could take any further decisions a step removed from a 'moment of crisis'.

This would dent my confidence in the car a little though - a low mileage engine is one thing. A low mileage engine with issues you couldn't fix would be another.

Ho hum.

A lot more reading on stuck cylinder head bolts suggests stuff like heating, or even cutting the heads off the bolts with a dremel. That might work on the outer ones - not a hope on the ones inside. I did search for a 3/4 drive 5/8 socket, but I don't think such a thing exists. The search was defaulting to 1-5/8 sockets...

I've also been researching the ebay price of breaker engines.... maybe for future reference. They're not unreasonable, but it would surely be a bit of a lottery.

Right. Bggr and F*ck. Thanks for the replies on the mudguards, Gents, but that question's somewhat on the back burner now.

I think I'm facing a serious 'reappraisal' moment.

Armed with my 16mm impact socket, and my impact gun, I went back out to the garage. According to the data sheet (I've just checked) the gun will deliver 610Nm of torque. It is making no headway at all with these bolts.

So I tried the manual approach. On #2 bolt (the one tucked into the recess, with the head covered in nice, slippy old engine oil) a 600mm 1/2 breaker bar with a tube on the end, giving a 4.5ft lever, and my 16mm single hex plug socket. The socket snapped.

I hate giving up on things like this, so I "could" get a 3/4 drive, 5/8 impact socket (if such a thing exists - doesn't seem so on the basis of a quick google) and drag my 3/4" breaker bar out of the back of the drawer and try this with a 6ft scaffolding pole, but short of that, I think I've thrown everything I have at this. 16mm doesn't seem like too good a fit, I have to say. I now also realise that the 5/8 one on the way to me will probably be too 'fat' to get onto some of these bolts. Before taking any final decisions I'll probably get a deep 5/8 impact socket sent up (non for sale locally) and try that. But that would really be me having shot my bolt - pun absolutely not intended - I'd have nothing else to go to short of the grinder.

"Rather annoyed" locking up the garage. Calmed down a little now, but it's still a watershed moment I feel.

I guess I could just 'weigh it in' - not really keen on that, because I don't like giving up on things, but common sense has to come into it somewhere.

I could maybe take a grinder to the head, butcher it and get a reconditioned one, but if I can't get the bolts to shift with heads on them, I can't see that it's going to be any easier as a bare stud.

Buy another one, and strip this for parts?

So I'm looking for thoughts and other suggestions please?

A recon engine (quick look) is the best part of £5,000 and that doesn't seem sensible; spend a few £100 and inherit someone else's problems? that doesn't seem too sensible either. Graduate from planning to only remove the heads, to lifting the engine out and take it to a local machine shop...? I'd have to invest in an engine crane and other bits and pieces.

Don't really know. Not a happy bunny I'm afraid. I think it's compounded by the fact that I've run into this brick wall on the very first head bolt.....

This all happened about an hour or so ago, so still quite fresh. I suspect if I sleep on this, weighing it in might emerge as the more sensible approach, cutting my losses.

If I was to put the wheels back on and get it trailered to a garage, do they have any magic tricks they could use to get round a problem like this?

Like I often say, any suggestions gratefully appreciated, but particularly tonight!

Thanks guys - I'd have replied last night, but my ipad couldn't open the site for some reason.

Today, I have bought a 16mm single hex impact socket. That should see me right. The gun has some serious grunt if needed. I've actually also ordered a 5/8 socket too, because..... well, just because!

On the mudguard question. I can feel that there's some sort of metal strengthener inside the rubber. Because I haven't got one off yet, I can't tell if it's fully enclosed, or if a new one could be 'slotted in' to the plastic sleeve?? If it's mild steel, in a place like that. it's always going to rust and disappear quickly.

Would it be acceptable to just cut a P38 mudguard shaped piece out of a larger one where there's no metal stiffener - like a lorry mudguard - and then screw that in place; or does that belong to the Order of Much Naffness?

Not so much progress since then - but trying to squeeze in a couple of hours after work.

Yesterday I managed to get the LH exhaust heat shield off, without removing the wheel arch liner. Thought I wasn't going to manage, but some rather risquè grinder work saved the day. Health and Safety guv? Not so much. Manifold itself off this eve, but that's were work ground to a halt. No pun intended..... A bit of a 'down' today.

Tried to get the first head bolt off on the LHS - why do you have to start with the most awkward one? And why are they16mm heads? What an awkward size. I assume there's some valid engineering reason. I tried with a bi-hex 1/2 socket - but that was at great risk of rounding the head. The only single hex 16mm I have is on my 3/8 set - and I just can't generate enough grunt on that with a 450mm breaker bar. My wonderful impact gun..... doesn't have a 16mm socket in that set.

So, had to call that a day before I dug myself into an even more difficult hole. I'll get a 16mm impact socket tomorrow and have at it again.

Then I thought I'd move to the RHS - no way I'm going to get that heat shield off with the wing liner in place. 3 of the fixings on the LHS needed coaxing - if it's the same this side there's just no access.

No probs says I: "Off with the wing liner!" ... eh, no. That mudguard ain't going anywhere without meeting Mr Grinder again - but I didn't want to do that without checking that it wasn't an obsolete part which was like rocking horse poo, and would cost a small golden egg. So, once again, work ground to a halt. (Edit - phew! Mudguards don't seem too expensive...... mine are going to meet a sticky end tomorrow then!)

I know the torque setting on the head bolts is 20Nm + 90' + 90' - but what does that roughly equate to once they've been in there for a number of years? They seem seriously tight to me. Assuming I can find a 16mm impact socket, is it common for the bolts to snap on the way out?? That would definitely leave me in a deep, dark hole.

Also - a little puzzle. For the LH head, workshop manual details a sequence for removing the bolts; and a different sequence for tightening. The RH head shows a removal sequence, but then only refers to 'tightening them in the indicated sequence' - but there isn't one. Do you use the same RH removal sequence on assembly, or extrapolate the LH tightening sequence?

Any words of encouragement greatly appreciated tonight!

Thanks guys,

Well, both heads are definitely coming off this time!

I completely see why it makes sense to do the water pump at this stage - a new airtex one will be in the post this week. Also waiting for a 36mm spanner to get the fan off - only got up to 32mm at the mo.

I think I'll 'chip away' at it evenings this week, try and keep the down time minimised.

There will also be lots of photos at the 'head off' stage to see what the collective opinion is. I have a reasonable machine shop in town if a good clean or even a skim looks necessary, but no point second guessing that at this stage. I'll find out soon enough.

"What have you done to your Range Rover today?".........."F*cked it, mate!" - well, it certainly isn't going anywhere in its current state.

Before that though, yesterday was finishing off the rear suspension. That all went pretty good to be honest. Two exceptions.
Firstly, the bottom nuts that came with the shockers. They are made with some sort of integral lock washer (not nyloc). If you try and tighten them using two spanners - 6mm and 19mm - you'll get nowhere. The nut requires a lot of torque to tighten, and the little 6mm thing on the end isn't good enough. It's a case of grabbing the shock body with some grippy gloves on, and running the nut up with the windy gun. Well, that's fine, but what happens if you don't have one of them? I never used to. I'd have been really p!ssed off trying to fight with that. Grrr. It's a non-standard, finer thread, so I couldn't just use any of my nyloc ones. I get that this all makes sense on an assembly line, where they all have power tools to hand, but it's a bit of a pain for the poor sod who tries to do the job afterwards, lying on his (or her) garage floor.

Secondly - more entertaining! As Strange Rover said above, the EAS sensor on the OSR is 'fuckered'.... definitely!
The bit that goes into the radius arm...... just half disappeared. I had to drill into it, tap an M3 thread in and then put that into the arm.

So far, so good. Then the actual sensor part just cracked and fell out of the chassis.. had to tie wrap that back into place...

And then the lower arm kept popping out of the rubber 'elbow' swivel. Had to hold it in place with an R clip.....

I wasn't planning to cross the Sahara - just get it out of the garage and turned round without throwing a faulty fit - but it was still all over the place. They don't make things like they used to! Anyway, it's all on, doesn't appear to leak, and I'll get some new ones and make up a set of calibration blocks.

Then I moved on to the infinitely more interesting task of stripping off the top of the engine. You've seen the pics before no doubt, you go from this

to this....

This is where I left things. Covered it up, and closed the garage. I have a little parts list to sort out before phase 2 - taking the wing liners off and tackling the exhaust heat shields and manifolds before lifting the heads themselves.

I started this to tackle a coolant leak, at the back of the valley gasket, and having got this far, it's good to see that it does still look as if that was the source. Both of rearmost bolts, (L&R) where the inlet manifold goes onto the heads, were barely tight at all. Finger tight at very most. Same for the rocker covers actually, barely tight at all. It's not so obvious in this pic to be honest, but there's definitely red traces of coolant at the back there, and onto the top of the bellhousing.

(valley gasket pic)

I quite enjoyed myself today, to be honest. It all went more or less by the book. I think the only casualties have been the hoses to and from the heater. They were well bonded on. I decided life was too short to muck about with them, and cut them off. Oh, and I had to go to Halfords to get a bi-hex long 8mm socket to take the rocker covers off. I thought I had all the tools I'd need, but there's always something.

So the questions (there's always questions!)

Different colours inside the rocker covers. Right hand (left hand in the photo) is darker; pass. side noticeably lighter. Does that mean anything?

front end of the RH head gasket - does this look like a leak? And did they scribble on them in marker pen in the factory??

So far, so good though. Without pushing myself too hard, it's all coming along OK. Of course any monkey can take things apart, the fun starts on reassembly, but that's for another day.

Perfect Richard, thanks very much indeed. Couldn't ask for better than that.

Will get the rear suspension done, and the car back on the level; turn it round so that the bonnet is in (any!) sunshine, and crack on.

Hi guys, hope all's good with you all.
I'll post this here in the hope that it catches enough folks' attention and save a separate question thread - though I guess that's what a forum is for!

My ARP stud kit eventually arrived in the post yesterday, so that's me more or less able to tackle the valley gasket, and head gasket. I've read lots of threads and guides on the web, but still have a few questions. I'm sure the answers are 'out there' somewhere - but God knows how many pages I'd have to visit to sift it all out!

So here goes - if you can offer any advice I'll appreciate it as always. Car is a 4.0L, 2000MY, with ca. 75k miles only.

1. I had simply thought I'd get the heads off, new gaskets, heads straight back on, sorted. As there is no anticipated issue with the heads, I didn't think of skimming or refurbing. Do I need to do anything, or would it just be a 'good idea' to get them checked out?
2. I've seen something (PaulsP38a website) that suggests renewing the tappets and rockers. Again, I'm not aware of any issues with mine. Does this make sense?
3. I think I will do a general 'service' as part of this - plugs, HT leads, air/oil/fuel filters, serpentine belt - as I've no way of knowing when this was last done. If anything looks obviously 'iffy' when I strip it down, I'll replace that too. But is there anything else that just "makes sense" to do pre-emptively as part of such a substantial job?
4. I got the valley gasket kit from Turners. Don't know the manufacturer of the valley gasket (heads are Elring). The Paul'sP38a site suggests using a Payen valley gasket. I hadn't noticed that till last night. It's not a big extra cost - ca £14/15. Is it likely to be any better than what I have?
5. Any other 'hard lessons' you guys have learnt along the way that you'd be willing to pass on...?

Thanks as always.

Pics and progress will appear here as and when!

^^^ Now you mention it George, I think you're right. I'm pretty sure I'd have followed the instructions anyway - but your reply gives me a little more confidence there.

StrangeRover - the solenoids were indeed all very carefully marked and paired on re-assembly. I have a Nanocom, with EAS readings, and while I can't remember any detailed numbers, I'm pretty certain they were a looooong way from +/- 2 bits apart.

I'll get some Dunlop ones ordered - and make up some calibration blocks.