Zel's Eclectic Fleet Blog (Volvo, Rover, Trabant, Invacar & Occasional Distractions)

[Zelandeth]

About that wiring diagram...

This is what we started with.



Not exactly user friendly.

After I'd been left alone with it for a few hours.



Still needs a bit of tidying up, but isn't that several orders of magnitude easier to follow now? This is also a vastly scaled down version - the original is about 7000px wide, and currently has about ten layers as I'm still meddling with it.

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]

I had a sneaking suspicion that I was facing issues with the head gasket on the Rover. Primarily based on the amount of gurgling and nonsense from the radiator and the tendency for it to immediately violently dump about half the coolant the moment the thermostat opens.

Did a really quick and dirty test to see if I was dealing with combustion gases getting into the cooling system.



While it might be a very crude test, it's pretty conclusive! That glove started to inflate the moment the engine was started. There's only one place that can be coming from, and that's the cylinders.

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...



I guess before I do go pulling it apart I probably should check that all the head bolts are actually tight (with non composite gaskets like this it *can* actually be that simple sometimes) but I'm not expecting miracles. Worth checking though as I've no idea what work has been done to the engine beforehand. I need to pull the inlet valve cover to change the gasket anyway so may as well do that at the same time.

Project Pinball has taken a few steps towards functionality today in that I think everything needed to get the PC side up and running is now here.



My plan is to get the absolute basics up and going first before we start worrying about the extras. Not least because my interface board isn't likely to turn up for at least a couple of weeks yet. That is essentially just building a PC into a massively oversized case and setting up some software though, so shouldn't be too difficult. Even if it does mean I need to do battle with Windows 11 for the first time which I'm really not looking forward to. At least once it's set up here I won't have any need to interact with it much beyond seeing startup and shutdown screens.

[Zelandeth]

Finally got a chance to (very briefly before it started tipping it down) look at the Rover today. I can confirm that the head bolts are indeed tight (well as tight as spec anyway - all of 50 lb/ft for the big bolts and 30 for the little ones). Guess it's coming off then!

Looks clean enough though - well up here where it's easy to get to anyway - what's under the exhaust valve cover really will tell a more full story I think.

[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.



I was pretty sure the valve clearances were out 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. No reason not to just do the exhaust side clearances anyway I guess given they're not going to be disturbed.

[rich.]

Will you be fitting harder valve seats when the head is off?