Zel's Motoring Adventures...Volvo, Renault, Rover, Trabant, Invacar & A Sinclair C5 - Updated 20/08.

[PhilA]

The brake pedal assembly is the same as mine. Don't forget to grease the fulcrum pin. 

Horns of that type don't care which way around they are wired. Most likely the points are corroded and/or badly adjusted.

Phil

[Zelandeth]

15 hours ago, PhilA said:

The brake pedal assembly is the same as mine. Don't forget to grease the fulcrum pin. 

Horns of that type don't care which way around they are wired. Most likely the points are corroded and/or badly adjusted.

Phil

Cheers, good to know.  I'll pull them off shortly and see if I can convince them to live again.  

Does anyone have a good 110 wiring diagram?  The one in the manual I have is tiny and bloody hard to read.  Colour would be even better, but I'll take what I can get.  Trying to search on Google just gets me about 50,000 Land Rover 110 results.  The wiring in the 110 is quite fundamentally different to the other P4s so it really does need to be the right one.  It's not the end of the world, and I could probably just spend an evening redrawing the one in the manual in a more user friendly form if it came to it.

Reason I ask is that I'm starting to get stuck into what's actually going on with the headlight circuit.  

The way the lights *should* work on a P4 is that this switch on the dash when flipped to the right turns on the parking lights, and to the left turns on the panel illumination, side & tail lights.

Flicking the rearmost stalk on the right hand side of the steering wheel should then energise the dip/main circuit.

The one nearer the steering wheel is the indicators.

Main/dip is toggled by the foot switch to the left of the clutch.

The instrument panel illumination can be adjusted using a rheostat that looks just like a switch on the other side of the instrument panel.

There has at some point obviously been an issue in this car.  While the park/side switch works normally, the dip switch has been disconnected and replaced by this one down by the choke.

However looking closer at things I don't think they have just interrupted the feed to that switch, as if you look closely when you turn that switch on, both main and dip filaments are lighting at the same time when on dip.  

The wires to the dip switch should be red/blue and blue.  A little digging behind the instrument panel, sure enough I found these.

At which point I got more confused.  The switch tests absolutely fine.  Less than 0.1 ohm when closed, and no fault to ground.

There definitely has been some hacking going on in here.

That brown wire taped in is one of the ones that goes to the added switch, the other is jumping power from the park/side switch.

I'm 99% sure that the three connections in question are the connections to the disconnected switch and the missing one which should hook up where the brown one is on the park/side switch.  It's actually easier to see the colours there than in person.

I just want to get a better diagram so I can see what exactly they have done (and document it!) before I go and change anything.  It wouldn't be the first time I've gone and reversed mods like these and things have *just worked* afterwards, leaving me completely at a loss as to why things had been hacked around, and questioning what was going on for ever more.  

It's also possible that the dip/main issue is entirely at the headlights themselves as well, they have been replaced - they could just be wired wrong and it's nothing to do with what's going on behind the dash.

The torrential rain this morning has also identified that there's some water getting in on the driver's side of the windscreen.

Hopefully a bit of Cpt. Tolley's will improve that.  I'd rather not have to faff around replacing screen seals.  The rear windscreen doesn't seem to leak though as far as I can tell, which is definitely better than was the case on the previous one I had.

[SiC]

22 minutes ago, Zelandeth said:

It wouldn't be the first time I've gone and reversed mods like these and things have *just worked* afterwards, leaving me completely at a loss as to why things had been hacked around, and questioning what was going on for ever more.  

If reversing bodges does fix it then I wouldn't be surprised on a P4. They have by far the most complicated light switch selection procedure of any car I've ever driven! I really wouldn't be surprised if the bodges are from someone not understanding how they work. 

[MorrisItalSLX]

I thought I would be able to help with the wiring diagram, but the manual I have is a pre-110 edition.

But I’m sure if you sent Rover a Telex they would be able to organise a wiring diagram for you.

[LightBulbFun]

22 minutes ago, Zelandeth said:

The one in the manual I have is tiny and bloody hard to read.

if the manual you have is an original physical copy, could you stick the wiring diagram page(s) through scanner at All of the DPI and then print it out larger?  

[PhilA]

Hackery probably because the seperate switches were simply misunderstood.

[High Jetter]

58 minutes ago, Zelandeth said:

Does anyone have a good 110 wiring diagram? 

Maybe parts cat has the answer. 

[Zelandeth]

49 minutes ago, LightBulbFun said:

if the manual you have is an original physical copy, could you stick the wiring diagram page(s) through scanner at All of the DPI and then print it out larger?  

That's probably what I'll do - but may as well colour code the lines while I have it in the digital domain anyway.  It's obviously a scaled copy of another diagram though as the pin markers on switches are nearly invisible.

1 hour ago, SiC said:

If reversing bodges does fix it then I wouldn't be surprised on a P4. They have by far the most complicated light switch selection procedure of any car I've ever driven! I really wouldn't be surprised if the bodges are from someone not understanding how they work. 

That's not impossible to be honest.  You'd think they'd have tried to figure out where the wires they've disconnected originally went though...or am I applying too much logic there I wonder...

We'll get there, just might take a bit of time.

[Zelandeth]

Before:

Not exactly user friendly.

After:

Still needs a bit of tidying up, but isn't that several orders of magnitude easier to follow now?  Even with the compression applied by the forum software, you can actually SEE the respective circuits at a glance rather than having to spend five minute squinting at it and inevitably losing your place.  The original scan was at 1200dpi, so the original is something like 7000 pixels wide.

Key to Item Numbers on the diagram - in a format you can actually scan through rather than a totally unformatted wall of text.  Especially helpful as the sequence of numbering isn't exactly easy to follow in some areas.

1  Generator

2  Voltage Regulator

3  Ammeter

4  Battery

5  Starter Solenoid

6  Ignition Warning Light (Red)

7  Ignition Switch

8  Starter Motor

9  Clock Illumination

10  Speedometer Illumination

11  Grouped Instrument Illumination

12  Number Plate Light

13  Number Plate Light

14  LH Tail Light

15  LH Side Light

16  RH Side/Park Light

17  RH Tail/Park Light

18  Main Beam Warning Light

19  RH Head Lamp Main Beam

20  LH Head Lamp Main Beam

21  RH Head Lamp Dip Beam

22  LH Head Lamp Dip Beam

23  Heater Motor

24  Horns

25  Horn Push Switch

26  Parking/Side Light Switch

27  Boot Light Switch

28  Boot Light

29  Dash Illumination Rheostat

30  Panel Illumination Fuse (3A)

31  Side/Dip Head Lamp Switch

32  Side/Main Beam Foot Switch

33  Heater Motor Rheostat

34  Horn Relay

35  Fog/Spot Lamps – Where Fitted

36  Clock

37  Front Interior Light & Switch (combined unit)

38  Front LH Door Switch

39  Front RH Door Switch

40  Rear LH Door Switch

41  Rear Interior Light

42  Interior Light Switch LH

43  Rear RH Door Switch

44  Rear Interior Light

45  Interior Light Switch RH

46  Windscreen Washer Pump Motor

47  Windscreen Wiper and Washer Switch

48  Windscreen Wiper Motor

49  Fuses A2 and A4

50  Ignition Coil

51  Brake Light Switch

52  Reversing Light Switch

53  RH Indicator Tell Tale

54  Indicator Flasher Unit

55  Indicator Stalk

56  LH Indicator Tell Tale

57  Instrument Panel 10V Voltage Stabiliser

58  Coolant Temperature Gauge

59  Fuel Gauge

60  Fuel/Oil Level Selector Switch

61  N/A

62  Distributor

63  RH Brake Light

64  LH Brake Light

65  Reversing Light

66  LH Rear Indicator

67  LH Front Indicator

68  RH Front Indicator

69  RH Rear Indicator

70  Coolant Temperature Sender

71  Oil Level Sender

72  Fuel Level Sender

73  Oil Pressure Warning Light (Green)

74  Choke Warning Light (Amber)

75  Brake Fluid Level Float Switch

76  Fuel Main/Reserve Pump Selector Switch

77  Overdrive Fuse (35A)

78  Overdrive Solenoid

79  Overdrive Column Switch

80  Overdrive Throttle “Kickdown” Switch

81  Oil Pressure Switch

82  Choke Warning Light Thermoswitch

83  Brake Fluid Level and Handbrake Combined Warning Light

84  Handbrake Switch

85  Fuel Pump (Main)

86  Fuel Pump (Reserve)

87  Gearbox Overdrive Inhibitor Switch

88  Overdrive Relay

I think this was worth spending a couple of hours on as it will make continuing the detective work on what's been meddled with massively easier.  Yes I probably could have found one if I kept digging long enough, but I definitely learned a lot more about the car's electrical system doing it this way.

[Zelandeth]

Did a quick and dirty test today and have confirmed the head will need to come off the Rover.

Definitely have combustion gases getting into the coolant.  That starts inflating the moment the engine starts, even from stone cold.

Not the end of the world.  I want to change the water pump O-ring anyway, and the inlet manifold gasket is suspect, changing that will be orders of magnitude easier with the head off the car.  At least I won't need to disturb the exhaust which is usually the thing I'd dread most when pulling a cylinder head.

Everything I should need is already in stock.

Gasket is a little simpler than on modern engines...

[GlenAnderson]

Found this today, while looking for something else. If it’s any good to you then PM me your address and I’ll get it in the post to you. 
 

[Zelandeth]

On 10/07/2025 at 20:43, GlenAnderson said:

Found this today, while looking for something else. If it’s any good to you then PM me your address and I’ll get it in the post to you. 
 

Sorry, completely missed this post.  Can't be a bad thing to have a spare of.  I'll ping you a PM.

Finally got a chance to (very briefly before it started tipping it down) look at the car today.  I can confirm that the head bolts are indeed tight.  Guess it's coming off then!

It does look nice and clean in there though - at least up top where it's easy to clean.  What's under the exhaust valve cover may tell a totally different story!

[Zelandeth]

Had a very quick look under the exhaust rocker cover this evening (I was literally just taking some stuff to the garage, wasn't even specifically looking to do anything car related).

Not as clean as things on the inlet side as you'd expect, but still very clean for the age of engine I think.

Definitely not a horrible sludgy mess anyway.

I still love the valve gear on this engine.  It's just one of those bits of engineering that I find very pleasing to look at, and think it's a shame it's hidden away behind a cover all the time.

I was pretty sure the valve clearances needed setting given it's far more tappy than my last P4.  Testing purely with my eyes says I'm right.

The clearances are meant to be 6 thou on the inlet and 10 on the exhaust, and they're all at more like 50 I'd say.  Inlet should be set hot too, so are probably even further out!  Not going to worry about that until after the head gasket has been changed obviously, but I reckon that will quieten the engine down a lot.

[Zelandeth]

In case anyone wondered how the XJ-S I had a few years ago is doing, here's your answer.

Very well thank you very much.  She's had somewhere in the region of £15K spent on bodywork over the last couple of years.  There was a LOT of filler in this car it turns out.  The sills and rear suspension mounts were almost entirely made of it.  The intention is for the last few cosmetic bits sorted out in the next year or two and for a full respray to follow.  It's properly solid now though and is pretty well sorted mechanically.  I don't think it leaks oil any more...which is a huge change given that you can STILL see the oil patch where I used to park it on my drive something like four years on!

Biggest plus though is that the car has a properly weather tight garage to live in over the winter, that makes a huge difference to trying to keep on top of things with a car like this.  It is in regular use as well which is nice rather than just being an show queen.  My friend who now owns it is very much of the same view as me, cars are meant to be used and enjoyed.

This cat has definitely landed on its feet!

[Zelandeth]

Decided to chance taking the Rover over to a local classic car meet up today.  Less than a mile from home so figured it was pretty low risk, even if it threw a strop I should be able to limp that far.

Nice little mojo boost there I think.  Was nice to catch up with @Six-cylinder as well, and remind myself quite how pleasant a place the interior really is to just sit and natter to someone and watch the world go by.  

Kind of as I'd expected, on the way home when I attempted to use more than about 50% throttle it spat a significant portion of the coolant out of the system.  So yeah, definitely won't be getting driven again until the head gasket is changed.  I just need to do a bit of automotive Tetris to put it in the right place on the drive so I don't block anything in while doing that work, as I doubt I'll get it all done in one day.  Especially as I'll likely get the head professionally checked out while it's off the car which will probably take a week or three.

I wouldn't have minded taking this home either.

About as practical as an ashtray on a space hopper, but it looks to be a huge amount of fun.

Based heavily on bits of old Range Rover I think.

[Zelandeth]

Finally actually did something car related today.  Shocking news I know.

Step one was to start the coolant draining.  There's very clear evidence that someone has tried to solve the head gasket issues before - the tell tale coppery sparkle of K-Seal on the radiator cap.

Suffice to say it didn't work.  Surprise!

Not in the slightest.  It might buy you some time if you've got coolant getting into the cylinders via a leaky inlet manifold gasket on a K-Series, but it's not going to do bugger all if combustion gases are getting into the coolant as was the case here - given the release pressure of the cap on this engine is a heady 4 psi said leak was only ever going to go one way.

I was nearly smart when I went to remove the distributor (which I don't think you actually have to, but I figured it was likely to just be easier with it out the way, and it's just one bolt to pull it).  I made sure to mark both where the body was clocked and where no 1 was connected.

...And completely failed to note at which cylinder the rotor arm was pointing.  Oh well...it can only go in two locations, so I'll see if I can figure out where we are from the cylinder and valve positions.  Failing that I'll either get it right or get a spectacular backfire when I try to restart the engine.

I did also note when poking the distributor that the vacuum advance is *completely* seized, so I'll need to try to free that off before it goes back together.

Getting the bottom nuts for the carburettor off is precisely as annoying as I remembered as the brake servo is precisely in the way.

Maybe half an hour had the engine bay looking like this and us ready to start dismantling the engine.

Okay...let's preface that with "let me get the bigger socket set and the bit of old exhaust pipe I use as a breaker bar." Those head bolts were fluffing tight.  Most cracked off painfully violently, sounding like I was whacking an anvil with a hammer rather than unbolting something.

After a certain amount of swearing and mild terror that they were going to snap all the bolts were out and I could simply lift the head off.  Except I couldn't because I'd missed something.  The oil feed line to the head is actually external on this engine, fed from a rigid line through a banjo fitting on the rear of the head.  Once that was off the head all but tried to slide off the block on its own.  I was kinda worried it was going to be stuck to the block, thankfully not.

I used the time honoured method of keeping the bolts in the right places.

I had made the conscious decision to pull the head and inlet manifold as one assembly.  There were two reasons for this.  Firstly is that it is held on by an ungodly amount of nuts - 18 if I remember rightly - which are fiddly to get a spanner on at the best of times because they're a close fit to the surrounding casting.  All of the forward ones on the underside are an absolute swine to get to in situ because the brake servo and generator are in the way - I'm pretty sure getting to the front couple last time round I had to unbolt the generator to get clearance.  I'd far rather just deal with that off the car when I can easily get at things.  Secondly is that while it does indeed make things a bit heavier, I reckon it actually makes it an easier mass to manhandle as it's an easier shape to get hold of.  Having the carb side of the manifold 8" or so closer to me allowed me to just get a hand under that side then roll the head towards me and lift it clear of the car.  It ain't light but is entirely within the realms of doable so long as you've planned the lift.  Which I had.  Had a piece of wood on the garden immediately to left so I just had to lift, rotate by about 180 degrees then put it down.

Ain't this a funky looking setup?

And holy hell, look at the size of those inlet valves!

Thumb for scale.

The ability to fit far larger valves for a given bore size was of course one of the primary reasons the IoE layout was originally developed - even so it's a bit surprising seeing valves larger than in some big commercial engines I've been inside in a car engine.

I think we can pretty comprehensively say this gasket has been leaking in multiple places for some considerable time.  See all this oily crap down the side of the block?  That's all oozed out of the join between the head and block.

I think looking at this gasket it probably would be quicker to list the locations where it *hasn't* been leaking.

I don't know how old this gasket is, but this corrosion hasn't happened overnight.  Or in the last couple of years.

Next up I've got a fair bit of cleaning to do before we can see what we're working with.

I'm not going to be doing too much with the head myself as I'm just going to be chucking that at Headline MK to have it inspected and cleaned as they are far better equipped to do it properly than I am.  

Before I can do that though I need to get the head and inlet manifold to part company.

So far they have been unimpressed with my efforts.  Of course if I could find the dead blow hammer that might help, but beyond "in the garage" I've not a clue where it is.

This is where we left things for today after I fogged the cylinders with some oil.

Before anything goes back together I'll be taking the opportunity to clean up this side of the engine bay.  Likewise to pull the heater core to see if I can unclog it as that's going to be way less awkward while I have this much extra space to play with.  Likewise adjusting the steering box, given that you can actually *see* it at the moment, it's usually buried under the intake manifold.

While I don't want to get any more water into the engine than I can avoid, given how much of a slimy mess it is, I reckon that a *bunch* of degreaser and the pressure washer are probably going to be in its future.  I'll be here for a month trying to clean it by hand.

Even if the head gasket was fine, eventually I'd have had to pull the head to change this.

Which sits in between the head and water pump around this little stub.

Given that the water pump studs are renowned for snapping, the head is generally considered to be the safer of the two to remove.

Pretty simple getting this far to be honest.  Probably took me a couple of hours to get this far, though a full 30 minutes of that was probably faffing around removing the inlet manifold nuts 1/75th a turn at a time.  

Probably be a couple of weeks before reassembly can start, but it feels good to have got stuck into it and had things come apart pretty much as planned.

Does anyone know if the head bolts are intended to be single use?  The manual I have helpfully makes zero mention either way.  The torque setting involved isn't huge, but equally they could be ancient and been through god only knows how many heat cycles...Who even knows how many times in the life of this car this year has been off?  

[jonathan_dyane]

A satisfying job.

You can reuse the headbolts as long as they aren't obviously damaged.