RutlandRover wrote:

Cheers Richard.

If the threads for the exhaust manifold bolts are imperial does that mean the threads for the bolts that hold the mounting brackets for the alternator etc are imperial too?

I would think so, all engine bolts on the GEMS are imperial even though non-engine parts are metric.

I've had the spark plugs out now. They're all NGK LPG2 plugs (despite the engine not having LPG fitted, it's just a completely stock intake manifold) and the look like this:

Shame the pictures aren't showing up, they have a no entry sign showing so I suspect you haven't made them viewable to anyone. The NGK LPG plugs are the same as the NGK Iridium ones but with a higher price tag so would be fine if someone has money to burn. I pay £2 each for standard NGKs (BPR6ES), the equivalent Iridium (BPR6EiX0 are twice that (although will last about 4 times longer) whereas the special LPG plugs were will over a fiver each last time I looked and they appear identical to the standard Iridium. However, as the LPG2 has a 21mm hex, that does show you have GEMS heads. I suspect someone has fitted replacement heads at some point in the past and not specified Thor ones.

I'd be more inclined to look at the fusebox than the BeCM. BeCM does what it is told by other things so unless it is swimming in water and getting false grounds, it is unlikely to be the cause. A failing fusebox isn't uncommon and will cause all sorts of random intermittent faults.

It depends whether you are talking Disco 1 or Disco 2. The Disco 1 uses the non-electronic 4HP22 the same as used on the Classic, the Disco 2 uses the electronic 4HP22EH on the diesel and 4.0 litre petrol and the 4HP24EH in the 4.6 as used in the P38. The 24 can handle more torque than the 22 so using your original torque converter and bell housing on a gearbox with stronger internals makes perfect sense, particularly if the engine is to be modified in any way (or you spend half your life dragging 2 or 3 tonnes behind it like I do). I can't see there would be any point using a larger torque converter on a 4HP22. What are you trying to achieve?

Replying to David (RutlandRover) as I've not been here for 3 days due to driving my car again (Tuesday afternoon drive to Portsmouth with a Brian James transporter trailer on the back, Portsmouth-Caen overnight ferry, drive to La Rochelle, collect a BMW 330d that had almost died while the owner was on holiday a few weeks ago, drive back to Caen, night ferry last night, dropped BMW off at the owners local garage who have quoted considerably less than the €4,000 that the BMW main dealers in La Rochelle had quoted, and back home about 3 hours ago. Turned over 468,000 miles just before getting home too).

Anyway, flex plate isn't new, for some unknown reason, LR put a mark in yellow paint on them so the fact it still has it means it hasn't ever been changed. Spark plugs look to be some dubious make (Beru?) so probably came from the same place as the dodgily named oil filter and need to be changed. Stripped exhaust manifold threads aren't uncommon, usually the rearmost one of the RH bank or front one on the LH bank as these are the ones where it is awkward to get a socket on them square. Threads may well be 3/8 UNC if the heads have been changed and heads originally from a GEMS were fitted (see my reply to your other thread in Oily Bits). Easy test is to see if a 21mm spark plug socket will fit in the hole where the plugs go. If it will, they are GEMS heads but other than the machining identical to Thor heads.

I have repaired stripped manifold threads in the past using cut down Toyota head bolts. They are M10 thread (so a stripped 3/8 UNC thread hole will take an M10 tap perfectly) but have a slimmer bolt which is about spot on to cut an M8 thread on. That way I ended up with a stud that is M10 at one end and M8 at the other. Using a stud makes putting the manifold back on easier too.

Correction for Clive (and clarification for David), the GEMS used Imperial threads in a lot of places, particularly the heads. So 3/8 UNC is the correct thread size for both inlet and exhaust manifold bolts on a GEMS. There's quite a few other threads on the engine that went from imperial to metric on the Thor. The other difference between GEMS heads and Thor heads are the holes where the spark plugs sit. On a GEMS, they are larger which allows use of the BPR6ES plugs with the 21mm head hex but on Thor heads the holes are slightly smaller meaning a 21mm plug socket often won't fit so they use the PRF6N plugs with a 16mm hex. Other than that they are identical castings, just the machining is different. Classic heads had an additional row of bolt holes along the bottom so are referred to as 14 bolt heads (even though it has been found the additional bolts can cause uneven loading on the head gasket causing it to fail so the advice these days is to either not fit them or fit them but not torque them down).

Try setting the timing on a TVR 280i, that's a real pain too. I've just got a pair of front Dunlops from Craddocks. Mine are starting to look a bit iffy but have been there for 11 years and about 230k miles. I initially ordered them from LRDirect who accepted the order then refunded me as they were out of stock. Craddocks showed them as in stock at around the same price so I ordered from them. After a week of hearing nothing I rang them to be told that they were expecting a delivery and could either send them as soon as they arrived or give me a refund. I decided to wait and they turned up a couple of weeks ago. Genuine Dunlop, with a date code of week 48, 2021. At the same time I ordered rears from Island and they arrived in the usual couple of days. The ones on it had been fitted as soon as I got the car so they were a couple of years and 40k older and had definitely seen better days so were fitted immediately. The fronts can wait until I've nothing better to do (or it starts dropping overnight).

Clive603 wrote:

Richard would be on a regular change regime.

True. I changed mine as a precautionary measure when the engine was rebuilt. So the original one (at least I'm assuming it was the original) was still good after 285k and the replacement has been in there for a further 181k. The original has been in the boot ever since just in case.....

Or a can of freezer spray or a CO2 fire extinguisher. Either of them will cool it down......

Crank position sensor will fail when it gets hot and won't give any fault codes as the ECU doesn't know the engine is turning. Leave it to cool down, or give it a squirt of something to cool it down and it will fire up as normal. Until it gets hot again......

That didn't seem to match up with my memory so I just checked a couple of spare switches I have in a spare surround and they definitely push in from the front. However, looking at the way they clip in, I don't think you'd be able to release the clips with feeler gauges and, even if you can, you'd still need some means of getting hold of them to pull them out without damaging them.

Yes, the price of replacement bulbs is ridiculous and for some reason, the green ones are 4 times the price of the orange ones.

dave3d wrote:

The fluid in the TC will be transmission fluid won't it?

Yes it is, that's why you check the level with the engine running so the torque converter is filled.

Good point, he's using a diesel torque converter and bell housing on a 4HP24 so there won't be any change, just a stronger gearbox. The V8 bellhousing wouldn't bolt up to the diesel engine and the larger TC probably wouldn't fit inside the diesel bell housing. I understand the diesel TC and flex plate has only 3 bolts compared with 4 on the V8 so to use the larger TC would involve quite a bit of modification to lots of bits.

Will it? I've changed the original 4HP22 on my 4.0 litre V8 for a 4HP24 with the larger torque converter and other than changes being smoother and at a couple of hundred revs higher, there's no difference.

That's right, I had similar on the Ascot, although it was giving a stored fault on the Nano. Fault was for one ABS sensor (RH Rear in my case) which when I tested it was open circuit. Changed that and everything back to normal. When the fault comes up as soon as you start the car and before moving, it is something failing the self test and, in most cases, it will be a faulty sensor, either open or short circuit.

Agreed, probably just on the limit. Top it up to the max mark but only after you've turned the ignition on and waited for the ABS pump to stop. When the ignition is off, the fluid stored in the accumulator will gradually make it's way back to the reservoir so the level will rise. So if you check the level when the car has been standing for a while, it will be fine but will drop as soon as the pump runs.

That can happen if the TC isn't fully home when you fit the gearbox. RAVE says to stand the gearbox on end when fitting it, which I did, and it slides onto the splines but is a bit wobbly, turn it, it drops about half an inch with a satisfying clunk, is fully engaged and no longer wobbles. As the engine is tilted down at the back, gravity helps with holding the TC in place but a bit of wood shoved in the bellhousing inspection hole ensures it doesn't slip out.

Yes, check the voltage, or wheel speed, with the Nanocom. They should all read exactly the same and as you start to creep forward, they should all start giving the same output at the same time. I've seen one where one sensor was sluggish and was slow to start giving an output which was showing the same fault as you have. A tap with a mallet was all that was needed.

If you've got, or had, an ABS fault, Traction Failure will come up on the dash when you switch off. Is it still doing it or has it now gone away? Chances are the ABS sensor on one wheel has moved and a light tap with a mallet to push it back in will be all that you need do. If it was a failed sensor, it would be detected during the self test when you first switch the ignition on and would also store a fault that the Nano could read.

If the temperature doesn't change then there is a problem with the blend motors. When the ignition is first switched on, they are driven from one end of their travel to the other and the feedback from the blend motor internal potentiometer is checked. If it doesn't show full travel, the HEVAC shuts down the output to the blend motors so they won't move when told to.

If you aren't getting a change in temperature on the pipes to and from the compressor, then chances are you have a slight leak and the refrigerant has leaked away. A simple test is to see if there is any pressure in the system still. Static pressure (when the engine isn't running), should be in the region of 6 bar on both ports, dropping to 2.6 bar on the low port and rising to 10.6 bar on the high port when working. These pressures are at an ambient of 20 degrees C but will give you an idea of what is happening.

Hi and welcome. If you intend keeping the car, you won't go far wrong with a Nanocom (https://www.nanocom-diagnostics.com/product/ncom06-range-rover-p38-edc-diesel-kit), not cheap but it will pay for itself over time. A slightly less capable, computer based, solution is the RSW EASUnlock V4 suite (https://www.rswsolutions.com/index.php/range-rover-p38a).

There's some things you can check with a HEVAC that is giving you the book symbol. Does the temperature change on both sides when you go from Lo to HI, if not, you have a faulty blend motor. Are both blowers working, take the pollen filter covers off and filters out and you can see then down the hole. If only one is working, that will cause a problem. Does it have any refrigerant in it? Leaks from the top left corner of the condenser are common. I know seeing the AC compressor on a diesel isn't easy, but can you see if the clutch is engaging? If it has refrigerant but the clutch doesn't engage, check the connectors on the pressure switches, dirty contacts aren't unknown.