Mazda temperature gauge

[Northern Bongolow]

turn the ignition on(not running) the needle registers approx 5mm sweep up off the bottom, it doesnt change if the engine is running,or reving,until the correct temp overtakes the shown(false one).

[g8dhe]

Right, yes I have no problem with that, that is when the volts have gone from Zero to what ever the battery is resting at, about 12 volts in general, if it changes much when the engine starts but before the temperature rises then I would be a little surprised as that is when the balancing act applies for these particular gauges.

I checked our V6 when I made the mod's, got the engine up to temperature, and then switched the engine itself Off, but left the ignition on so the volts over the next few minutes went from the charging level 14.3 volts down to about 12.8 volts on the battery the needle didn't visibly move from the standard position for ours, after that I was happy that the actual temperature was decreasing rather than any effects from the battery voltage. The initial move up off the end stop is not unexpected, mine doesn't, but given the way the gauge is designed and built (for ruggedness rather than off-scale accuracy) I don't find it surprising

[Northern Bongolow]

cheers for the time geoff,so are you saying the gauges are crude etc etc.
dont answer if you dont want to

[g8dhe]

No not crude but very simply constructed for ruggedness and at the same time ingenious They actually use two coils, the coils normally balance out part of the magnetic field created to leave the needle resting off-scale but with double the sensitivity you expect, then the electrical circuit completes the "bridge" which balances out the supply voltage changes, the final result is that the temperature sensor brings the needle into the right range once it approaches the working temperature.

[Northern Bongolow]

[quote="g8dhe"] They actually use two coils, the coils normally balance out part of the magnetic field created to leave the needle resting off-scale but with double the sensitivity you expect,
thanks geoff,sorry to take this out of context, but this may be the problem ive experienced, when the 2 coils get out of balance.

[g8dhe]

Not saying its impossible Ady, but unless you have been in and played with the mechanism internally or bounced them around the floor a few times I would judge that its unlikely, either the coils would have to move in relation to each other or other parts of the mech. or turns within the coil would have to have shorted out, and I can only think that a very excessive current / heat would do that ?

[Northern Bongolow]

thanks geoff, they have probably had all of the above done at/to them over the years.

[mikexgough]

One mans Mason may behave the same as another mans Haydn, depending on the state of the plumbing.

As Mr M says.....
Mines a 12 o'clock and 12:30/13:00 when hard slog up hills like Hardknott pass or motorway slogging.....although it runs at 12:30 at 5c ambient....and has done since I went "Masoned",I guess that's down to bottom hose staying cooler (as per figures published on here) due to ambient temp differences.

My Mason did warn me last week that something was amiss....as the needle was at 13:00 in town (very unusual) and since then I tracked it down to a weak springed expansion tank cap.... fitted new cap...back to normal... (The cap helps to raise the temperature of the coolant, so therefore the 'stat then opens wider) then running "cooler" again - well Normal..... as for temp gauge changes with electrical load...not in my case either

[widdowson2008]

Been pratting around............again
If the needle on the modified Mazda gauge wandered in this sort of range, the green and red additions would make it more readily apparent what is happening...............don't you think? and they would be simple to make and stick on. (not the text)

[mikeonb4c]

Been pratting around............again
If the needle on the modified Mazda gauge wandered in this sort of range, the green and red additions would make it more readily apparent what is happening...............don't you think? and they would be simple to make and stick on. (not the text)

It's very nice, but I think though that the most valuable thing to have is an audio warning (like LCA, Mason, TM2 all have) as referring to the temp gauge continuously encourages driver distraction and/or may cause a critical event to be overlooked). Pilots should be looking out the window, and aircraft be fitted (which many are) with a stall warning alarm etc.

Also, I would shade through from green to red (or have an orange section, with apologies to those with red/green colour blindness, which also needs addressing in the above schema), because there is no one point where things move from normal to abnormal: things like whether the engine is having to work v. hard in a hot climate may casue unusual, but not critical, temp rises. etc. etc.

[munroman]

Best practice is to have gauges marked so that anything outside normal range is highlighted, e.g. having green all the way from cold is not actually a good idea, as a removed/stuck open thermostat is also not good for the engine, with an audible warning as a failsafe for overheats.

Perhaps one of our 'multiple personality' posters might comment on that, as I don't have the relevant qualifications, merely experience of 'the university of life'.

[mikeonb4c]

Best practice is to have gauges marked so that anything outside normal range is highlighted, e.g. having green all the way from cold is not actually a good idea, as a removed/stuck open thermostat is also not good for the engine, with an audible warning as a failsafe for overheats.

Perhaps one of our 'multiple personality' posters might comment on that, as I don't have the relevant qualifications, merely experience of 'the university of life'.

I'm the reverse of course: a multiple personality (most of them cracked) who posts under only one name

[munroman]

Best practice is to have gauges marked so that anything outside normal range is highlighted, e.g. having green all the way from cold is not actually a good idea, as a removed/stuck open thermostat is also not good for the engine, with an audible warning as a failsafe for overheats.

Perhaps one of our 'multiple personality' posters might comment on that, as I don't have the relevant qualifications, merely experience of 'the university of life'.

I'm the reverse of course: a multiple personality (most of them cracked) who posts under only one name

Perhaps you can draw some comfort from the concept that a schizophrenic is never alone!

[widdowson2008]

Yep - you're both probably right.
I was looking at it from the control/diagnostic perspective - too much information.
Need to take up golf.

[munroman]

Yep - you're both probably right.
I was looking at it from the control/diagnostic perspective - too much information.
Need to take up golf.

I hope you're not talking about Mike again, you know how paranoid he gets, (and him as well)