After market gauges.

[jeremy]

Mulley has asked me the differences between electric an mechanical temperature gauges and also what range of boost gauges should be fitted.

An electrical temperature gauge is connected by electric wires to a sensor in the engine - obvious I know, but electrical wires are easy to fit - but the sensor may not be. Mechanical ones have a link via a fine tube to a sensor (which is like a bulb) which is fitted into the cooling system.

The probalm with the mechanical ones is that the tube is sealed from the gauge to the sensor (about 6ft long) and so great care has to be taken not to damage the tube during fitting. A hole big enough for the tube and any fittings has to be provided and of course the surplus tube must be coiled up out of the way.

The mechanical one may be more reliable, quicker reading and more accurate - but is probably easier to install in a competition car where looks and originality aren't the problem. Finding routes in modern saloons isn't easy.

Incidentally I used a TIM gauge on mine - and even after buying their kit of adaptors - wasn't confident I had the correct one to fit the sensor provided to the BX - which has a fine thread and seems to seal on a taper at the top of the threads rather than on a flat surface . . .

I had a broken sensor so I drilled out its innerds and bent the top flange so I could screw the Tim sensor into the thread - and surrounded the whole thing in some silicon supposedly conductive paste left over from fitting a new thermostat to my boiler. If I was doing it again I would solder an adaptor in and screw the sensor into that but I'd got the silicon all over it before I thought of that.

It works but I'm not convinced of its accuracy - must spend some time on it one day.

BOOST GAUGES - seem to be 1 or 2 barr max reading. BX should run to 0.9 bar max - so a 1 bar should be enough and give an easy reading of an over boost should you be lucky enough to suffer from one. If you intend to tinker with the boost - then get a 2 bar one.

[Stewart (oily!)]

I fitted a smiths electrical temp gauge, the sensor went into the hole on the thermostat housing where the head gasket failure light sensor used to live I nolonger have the details of the threaded boss i used but a decent supplier should be able to match you up if you take a standard sensor with you, Iwanted a boost gauge in psi and found a "fast and furious" branded one, the quality is nowhere near the smiths item and it has colour changing led illumination to lead the pipes/wires into thecar I drilled through the bulkhead next to the screenwasher bottle then made a grommet out of silicone.
Stewart

[Way2go]

The probalm with the mechanical ones is that the tube is sealed from the gauge to the sensor (about 6ft long) and so great care has to be taken not to damage the tube during fitting..

Very true Jeremy, Years ago when fitting one, the tube flicked & glanced against a live contact which resulted in the tube being treated as a fuse and severed.

[MULLEY]

jeremy - i did know the difference between the 2, i just didnt know which would be the best type to fit, so the mechanical one is best? i personally would have thought the electrical one, but that just shows i know next to nowt about cars....

Got your photo's by the way, cheers for those. Stewart had his mounted in the Tweeter grill, i have seen some pods that you can mount on the piller which may look aesthetically pleasing, but can i find any that will fit??

I think i will have a look on e-bay for some guages as there seems to be a huge variation in prices & i guess quality.

Thanks for your help on this one.

[jeremy]

Loads of gauges here - including ones that change colour.

http://www.speeding.co.uk/acatalog/Engine.htm

Successful fitting is important and I for one had not handled the capillary tube mechanism before and thought that an electric one would be easier to fit - so I used one of them.

Many manufacturers have gone to considerable trouble to cut or eliminate holes in the bulkhead to reduce noise transmission. I don't think the BX is in this class but this was a solution adopted by Jaguar for the Series 2 XJ6 and even my Mk 3 Cortina had no cables going through the face (Upward facing plugs at the back of the bulkhead under the bonnet etc) So some care has to be taken before getting the holesaw out.

I fitted a TIM voltmeter to my Father's Range Rover 4.2 as he was having trouble with the battery going down which was probably due to the drain by alarms, seat computers and other junk which was on standby all the time - and gives some re-assurance that all is well when its used. This is extremely accurate - and of course easy to check with a digital meter.

Absolute accuracy in car gauges is seldom essential - a high or low reading usually being the warning that is required.

The difficulty is finding suitable power sources to tap. I recall using the back wiper supply for the power for my temperature gauge, finding the wire to the yellow warning light and using that, using a convenient switch earth and tapping the clock dimmer feed so the gauge illumination comes on with the side lights. Its brightness is about right so I haven't given it a separate dimmer but should get some green gglass paint for the bulb so its glow matches.

Both the TIM gauges I have bought have come with a panel fitting bracket ( Flat strip bent in 'U' shape) which cannot fit as the cut out to clear the illumination bulb socket is in the wrong place. Amazing for something nicely made coming out of a sealed box! It hasn't mattered as I've used pods for both - and the only way I've found to secure them in the pods is to wind the body with tape so that it grips the pod. A bit crude but it works and doesn't vibrate!

Fitting difficulty - not easy - and I enjoy car electrics and keep a good stock of terminals and have a good electrical toolkit.

I fitted the temp gauge - and realised that I could drive to work (5 miles) before 6am without getting it to move! - then there was the fun of fitting the new thermostat (the huge one for early TD's) when the studs snapped!

[st gilles]

I seem to remember the same discussion happening on the forum of a different car I used to own (Toyota Minibus thingy with all the windows in the roof). Anyway, although this car was fitted with a temp. gauge it was not calibrated finely enough and with the engine having its own problems led the owners to want a better gauge. Most observed that it wsn't the exact (correct) temperature that was required it was the ability to differentiate between when it was running normally and when it started to overheat (a bit like the light of death in the BX.....if its on, its too late).
They came to the conclusion that having fitted the 'new' gauge, that you would observe where it sat to work out its 'normal' position and thus be able to see when it started to overheat.........I think the same applies here; up to a point it doesn't matter if the reading is 90 deg 'c' or 100 deg.....its the difference and the ability to see that difference early enough and be able to do something about it before its too late. Hope that makes sense.

[MULLEY]

Many thanks for everyones posts on this thread. Does anyone know how to fit an electrical temp guage to a TZD?

[adamskibx]

I have a white dialed "Tim" aftermarket one in the GT, descretely below the main dash, and its been great. It came with a variety of adaptors, one of which fitted the thread of the thermostat housing where the lamp of death used to be. Its a good idea to use the high temperature lamp of death hole, so that you still get a warning lamp come one at the lower of the two extreme temperatures should something go wrong when you forget to look at the guage for a while.

[MULLEY]

Right i'm back again on this thread, i have now got my turbo boost & temp guages. Does anyone know if locating the guages in one of those pod systems that fits onto the front windscreen piller is feasable bearing in mind that both guages need to be connected upto some power for them to work.

Everyone who has responded seems to have their guages in different places, was this because of wiring issues?

[jeremy]

I did consider the pillar mounting - and would have got the wiring there somehow. I looked all over the place and couldn't find anyone selling pods round here and so only had the picture to go on, and to be honest it looked rather chunky and with bases etc I wasn't really sure what it would look like and how visible it would be.

I thought about using the centre tray - and if you look at my car carefully you will still see the pencil mark from when I was seeing what it looked like. I decided that it would interfere to some extent with the clock which I like and also we find the tray useful.

One day I may get round to fitting a boost gauge which I will probably fit to the right hand side of the binnacle below the temperature gauge. Should I feel the need to get really worried and fit an oil pressure gauge and a voltmeter they would probably go on the opposite side - similarily mounted.

BX's are like many other modern cars in that there is no-where obvious to fit additional instruments and a compromise has to be reached between function and appearance.