Suis je une totalement numpty - ?

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
Linegeist
Posts: 96
Joined: 20 Jun 2003, 20:24
Location: Stratford upon Avon
My Cars:

Suis je une totalement numpty - ?

Post by Linegeist »

Having had my radiator fan relay fail on my aged but much-loved 1.9 BX GT last year in the height of the French heatwave, experiencing that awful sinking feeling (no, not the suspension, silly) when BOTH temperature warning lights came on within seconds of each other (traffic jam – nowhere to stop - people trying to warm their croissants on my cylinder head)[:(][:(] I’m a bit leery of those two little lights that basically tell your engine will self-destruct in several nanoseconds! The coolant had just the faintest whiff of that fateful head gasket smell about it afterwards – but, 15,000k later it looks like I’ve got away with it.
So, I decided I’d fit an aftermarket temperature gauge. For good measure (and to balance up a nice little dash-top binnacle I’d fabricated for the purpose) I thought I’d fit an oil pressure gauge as well complete with a manual fan override switch and a warning light to tell me when the damned thing was on. Paranoid? Moi? Tsk!!!! [:D]
Off I trotted to my local Norauto (Basically a French Halfords, and similarly useless) and got a nice little electrical ensemble complete with senders “pret a porter”. The problem is that, having whipped out the higher of the two warning light senders from the rear of the head, I now find that none of the adaptors for fitting the replacement actually fit!!! I assume this is old Andre's lot ploughing their lonely furrow again in the interests of ‘La Uniquement d’Citroenne’!
So, how to fit this dratted thing into a hot water supply without either tapping the thread in the head (at THAT angle you’ve got to be ‘avin’ a larf, intcha mister?) or turning down and threading an existing adaptor (I no longer have my lathe or my dies – Merde!)
Then I came up with the idea of cutting into the small diameter hose that comes off the thermostat housing and feeds the inlet manifold/choke/heater, introducing a piece of 16mm copper pipe. Neatly soldered into this pipe at 90 degrees will be one of the brass adaptors into which I can then happily screw my sender (sorry for any double-entendre there). Simply earth the piece of pipe with a piece of copper braiding and the sender should be nicely immersed in hot coolant that OUGHT to be within a few degrees of that found just behind the thermostat housing and will feed the gauge with a measurable and variable current…………………. Nes pas? [?]
Now this sounds too easy to me ……………….. have I missed something obvious? Even worse, is there a much easier way that’s staring me in the face but, because I’m BMC (remember them?) trained I can’t see it? Is there an alternative threaded takeoff I don’t know about (getting desperate now…….)
So, am I being a total numpty? [:)][:)][:)]
bxbodger
Posts: 1455
Joined: 23 May 2003, 03:34
Location: Lovejoy country (Essex!!)
My Cars:
x 1

Post by bxbodger »

See if you can get hold of a temp. gauge from the Tim Superdash range; I got one from ripspeed for about £30.00- this came with a range of adaptors, one of which fitted the warning light sender holes on my Diesel- a whole lot easier!!!!
God knows where in France you could get one from but they may be available for on-line purchase somewhere.
Your solution sounds OK as long as it's on the engine side and not the radiator side of the thermostat-otherwise you could have a jammed shut thermostat and never know until its too late....[}:)]
By the way, if it was a BMC A-series the thermostat housing would be seized on anyway!!!!!
User avatar
AndersDK
Posts: 6060
Joined: 21 Feb 2003, 04:56
Location: Denmark
My Cars:
x 1

Post by AndersDK »

Why not do it the easy way - find a suitable Peug/Cit sender/sensor from a breakers - fitting exactlty that strange 14mm thread in the sensor hole ?
To test the sensor before removal, simple do an ohms measurement on the sensor contacts. Any switch would read high ohms, any sender would read something within the 10 ohm - 10K ohms range.
You then need to calibrate sender and readout. Easy done by connecting either series or parallel resistor, to either readout or sender. Any non-linearity on readout scale should be ignored. Important part is you get a reliable and precise reading in the 90 - 110 degC range.
NOTE : It's important the removed warning switch is the HI-temp one, as the LO-temp one comes in as early warning, and stays on at higher temp.
A different approach could be to drill out the removed HI-temp sensor warning switch, and then fit a NTC resistor, with some chassisfiller (providing electric isolation, but still transferring heat), and suitable sturdy wires soldered on for connections.
The NTC resistor would be approx 1€, and the type deduced by measuring the sender unit you've got now : simply measure ohms value at known temp, then heat the sensor to a higher known temp, and record the ohm's again.
More fiddly - yes - but cheaper and tailored exactly to your demands.
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

Gunsons stock the Sunpro range of instruements as well as a range of adaptors. Do any of these help? - available mail order.
http://www.gunson.co.uk/
jeremy
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

BXbodger - where did you site your temperature gauge? Presumably its an electric one. The reason I ask is that its time I fitted one to my TD BX and the Tim electric one in a pod is probably the answer. One problem is where to put it - I have a short wife who grumbles she won't be able to see out!
Jeremy
Linegeist
Posts: 96
Joined: 20 Jun 2003, 20:24
Location: Stratford upon Avon
My Cars:

Post by Linegeist »

Thanks Chaps:
Anders, I do appreciate your input, as always (and the highly educational content of your post) but unfortunately I’m living in a technological backwater here, called France. Your average Frenchman will have an encyclopaedic knowledge of the local wines and cheeses and will happily discuss the latest political scene Ad Nauseam, but will find the idea of fixing anything more complex than a 3 pin plug terminally challenging. This means that the market for the bits you describe doesn’t exist – even a trip to an ‘electronics’ shop in Paris elicited no more than a pitying smile for “les loony Anglais”.
Jeremy, That’s it! Perfect. Adaptor kits ………… I just couldn’t figure out where to get them. I’ve contacted Gunson – and you couldn’t get a more helpful bunch. A pack of brass adaptors will be on its way shortly……all for the princely sum of less than a tenner including postage!!!!
The Cit BBS scores again. Thank you!!
jeremy
Posts: 3959
Joined: 20 Oct 2002, 16:00
Location: Hampshire, UK
My Cars:
x 2

Post by jeremy »

Linegeist
I have a temperature sensor (light type) sitting here on my desk at the moment and so far as I can see the thread is near but not convincingly 1.25mmm pitch. My thread gauge does not fit nicely but the 1.5 certainly does not fit, nor does the 1mm one. From what I can see the Gunson's ones are 1.5mm pitch. I saw a set in my local accessory shop on saturday but was not convinced that any of them would fit but didn't pursue it as the shop only had capillary gauges and I can't see how I would ever fit one without dismantling most of the car which doesn't appeal. I'm also concerned about a badly routed capillary tube chafing through existing wiring having had a car catch fire with me in it presumably from this problem.
But if Gunson's say it fits then this may be the way to go! - corrently looking at Tim gauges as they sell a black plastic mounting pot which won't reflect like the Chrome one will.
jeremy
bxbodger
Posts: 1455
Joined: 23 May 2003, 03:34
Location: Lovejoy country (Essex!!)
My Cars:
x 1

Post by bxbodger »

Jeremy;
I have the base model BX17RD with the big analogue clock.This gave up years ago,so I took its guts out,and cut a hole in the centre of the clock face and put the temp gauge there-right where I can see it!!!
It doesn't look too out of place apart from the colour.
Post Reply