Brake light switch and water pump pulley questions

[thegfb]

The brake lights on my '61 S1 FHC have stopped working and I don't think it's a fuse issue more likely the brake light switch. Can anyone advise me what is the correct location for the switch?
Regarding the water pump pulley - there is a rotational noise/squeak coming from the water pump pulley/fan belt interface. I have tried adjusting the fan belt to no effect, though if I rub a piece of yellow tyre marking 'chalk' against the fan belt (plain non toothed) while the engines running the noise stops for a while. The water pump pulley on the car is aluminium and it's been suggested to me that the noise is a resonance created by the fact the pulley is not steel. I've checked with SNGB as to whether a steel replacement is available but they can only offer the pulley in aluminium.
Any suggestions as to resolve the problem gratefully received!

[Moeregaard]

Your brake light switch should be attached to the junction between the left-hand frame rail and "picture frame" cross member, just forward of the generator pulley. It's got two wires coming from it, so it's pretty hard to miss. Jaguar relocated the switch to the servo unit sometime in late '65, so if your car has been retrofitted with later Series One brake bits this is a possible location.

Before removing the switch--and necessitating a complete bleeding of the brake system--remove the two wires and do a continuity check while someone steps on the brake pedal.

Have you tried applying a belt dressing to the offending drive belt? A resonance will have more of a "singing" sound, while a squeaky belt will just sound....squeaky. The belt's jockey pulley can also make noises, so that's worth a look as well.

[chrisvine]

A previous thread covered adding a mechanical brake light switch which might be worth considering:

http://etypeuk.com/forum/viewtopic.php?t=2530

I know AJ Autocraft are producing a suitable bracket if you go down the mechanical switch route and are unable to fabricate one

[PeterCrespin]

Before removing the switch--and necessitating a complete bleeding of the brake system--remove the two wires and do a continuity check while someone steps on the brake pedal.

Touching the two wires together IS the continuity/circuit check. No pedal pumping required. If the lamps come on (with/without ignition on, depending how car is wired) then the fault is in the switch. Early switches had two pins rather than two spade connectors. If it's one of those then even a dud might have some value to a concours freak?

Pete

[thegfb]

Firstly thank you for the responses - much appreciated.

Unfortunately 'life' has rather unexpectedly got in the way of addressing the problem so time constraits preclude looking at this properly. However a quick inspection under the bonnet and below suggests that the switch isn't where it should be! The car was a very early FHC and a Texas LHD example repatriated, I believe, in the late 80's and converted to RHD which might explain some possible anomalies. I haven't had the car in the air yet but a quick look under the car suggests that it might be located low down on the right hand engine frame towards the front just above the splash plate(?). There seems to be a hole in the plate through which I can feel/just about see what looks like two wires going into a couple of screw terminals. Squeezing my hand in over the top of the splash plate I can just feel a couple of pipes heading towards the area above where the terminals show. If I join the the two wires in situ using a screwdriver to check as suggested will this damage this damage anything or do I need to disconnect them first? Room to accomplish disconnection is very limited.

Thanks again

Gareth

[PeterCrespin]

If it's the stop lamp switch it won't hurt to connect them although they didn't use screw terminals as standard. Pins (early) or spades should be present. But assuming it's any kind of switch, merely making the contact between two poles should not cause damage, just complete the circuit. Do make sure you don't short to earth though - either via the switch body or surrounding metalwork.

Pete

[Robert Hiland]

The jockey pulley may be making a bit of noise. Is the belt running true? If not and it is slopping around a bit replace that pulley. The other culprit might be the bearings in your water pump showing their age.