DIY add on alarm to Sure Temp Sensor

[Driver+Passengers]

I'm using these mini 12V buzzer off eBay (http://www.ebay.co.uk/itm/10pcs-Tone-Al ... 5ae200e687) - 14p each. I believe they are the same as the buzzers contained in the front beeper box and the AFT beeper box.

Nice find - thanks . Do these contain the oscillator, i.e. connect DC and you get sound? If so that is far cheaper than the likes of RS or Farnell

Yes - 3.6KHz. Easy peasy!

[The Great Pretender]

Being really cunning... At a guess, you might even be able to install one of theses buzzers behind the A pillar trim on the drivers side.. (Lower down as the trim widens/flutes out?)



Sort of just below where i planted (hidden) the base for my turbo gauge...?

"Sound Pressure Level 90 dB min. at 10 cm, 12 V D.C." Should be audible there fer a def rocker like me!

Brill, but if you are really deaf a high intensity led as used in motorsport for a shift light fitted there couldn't be missed.

[tallbongo]

I'm using these mini 12V buzzer off eBay (http://www.ebay.co.uk/itm/10pcs-Tone-Al ... 5ae200e687) - 14p each. I believe they are the same as the buzzers contained in the front beeper box and the AFT beeper box.

Nice find - thanks . Do these contain the oscillator, i.e. connect DC and you get sound? If so that is far cheaper than the likes of RS or Farnell

Yes - 3.6KHz. Easy peasy!

Great. I suspected so, but at that price was concerned that the 3.6kHz was just the resonant frequency. Will be ordering some tonight






Some people have been in touch with me regarding ideas to make this more useful. I'm considering them at the moment, but please feel free to add any suggestions here.

One of my own ideas I'm seriously considering is putting the potentiometer to adjust the alarm levels on the circuit board itself and adding an illuminated switch to override the buzzer. The thinking behind this is that the buzzer is just to warn you that things may be going out of control and to keep an eye on the temp. If you are towing, stuck in a motorway traffic jam or are just on a steep slope there may well be nothing to be concerned about and the buzzer would just be annoying. By putting in an illuminated bypass on the buzzer you could switch it off, but the light would remind you it is off.

Would this be useful, or would you just prefer to keep a pot on the front to tweak upwards in these circumstances (you'd have to remember to turn it back each time)?

[jaylee]

Hi TB,

If it's any bearing on anything to do with this....

Background first, 4X4 diesel (SGLR?) with a Mason gauge fitted for abut the last 3.5 years... As you know i have a Sure gauge with the two probes fitted to the top hose outlet stub & heater outlet stub off the engine....

Prior to getting the Sure gauge, after a little research on here regarding "normal" temps & coolant system flow using one of these..



My Mason'd gauge sits about here....



BUT that is not indicative of what the Sure can read out on the top hose... There is an equilibrium kept up with the temp on a reasonably healthy engine system (I'm not claiming i have a tip top runner)

My observations are that (& bearing in mind the position of the engine temp sender for the modded Bongo gauge.!)
The higher the reading on the Sure (top hose) the lower it seems on the Mason modded dash temp!

One observation on my van for instance; i could be climbing a hill & the Sure can read 85.c? The Mason will be quite close to the red arrow.. As i hit the level out at the top of the hill, the Mason will drop & the Sure will climb & read about 92.c, (maybe a little higher?) then the Sure reading will start to drop back to the 80's...
Similar thing after a long bat on the flat, then slowing down. (Say exiting a motorway?)

I assume my system is doing its job, so i tend not to panic at this point...

What works for me is i would go by the alarm sounding on the Mason gauge.. If the Sure didn't read a climb in temp of the top hose (removing heat soak?) That's when i personally would worry!

I may have got it all wrong?!! (I'm still learning this mechanical stuff.)

[tallbongo]

Thanks,

I've heard of the Mason, but not really looked into it in much depth. I assumed it just used the Mazda temp sensor with a variable resistor instead of the DIY mod with the 100 ohm resistor.

...

My observations are that (& bearing in mind the position of the engine temp sender for the modded Bongo gauge.!)
The higher the reading on the Sure (top hose) the lower it seems on the Mason modded dash temp!

One observation on my van for instance; i could be climbing a hill & the Sure can read 85.c? The Mason will be quite close to the red arrow.. As i hit the level out at the top of the hill, the Mason will drop & the Sure will climb & read about 92.c, (maybe a little higher?) then the Sure reading will start to drop back to the 80's...

...

Is this just not lag due to different sensor positions (as opposed to the Sure dropping when the Mazda guage is climbing)?

If so, it does suggest that there could be a better position for the Sure probes. Is the Mazda probe actually in the coolant in the head (I've vague recollections of a thread where the procedure for changing it was gone through)?

Even if this is the best (non-immersed) position for the sensor, it is still better to have an alarm late then not at all.

I suppose it's possible to do a DIY mod to the Mazda guage, which I think would be a DIY Mason equivalent, for a faster response, but you wouldn't have the nice read out or the back up facilities of the Sure. Also, if done wrong you could end up with no temp monitoring!