Temp gauge reading with Mason alarm.

[dandywarhol]

Found the problem - temp sensor in head on it's way out - I guess a higher resistance made the gauge show cooler. Removed the wire to check sensor resistance and found the spade on the sensor loose - needs a new one as it's now knackered

[dandywarhol]

I'm likimg this thread, the temp gauge on my v6 with the mason stays around 11.30/12 ish can't make my mind up which even though the v6 isn't as prone i decided to fit one cause it a decidingly easier job than the water pump on my puppy which i have doubts about. The only time i get substantial movement on the needle is when in traffic or idling a long time when it goes 2/3 way up. I've got it on a run next month down the m/way be interesting to see what that chucks up, maybe it not compatable with the v6 Anyone else got any results on the v6 with mason, is it just a v6 thing

How do you know it dosn't have problems? Its coolant pipes have the same inherent fault as all Bongos

Y'mean they go hard with age?

[cheffy34]

I'm likimg this thread, the temp gauge on my v6 with the mason stays around 11.30/12 ish can't make my mind up which even though the v6 isn't as prone i decided to fit one cause it a decidingly easier job than the water pump on my puppy which i have doubts about. The only time i get substantial movement on the needle is when in traffic or idling a long time when it goes 2/3 way up. I've got it on a run next month down the m/way be interesting to see what that chucks up, maybe it not compatable with the v6 Anyone else got any results on the v6 with mason, is it just a v6 thing

How do you know it dosn't have problems? Its coolant pipes have the same inherent fault as all Bongos

I know it doesn't have any major probs at mo(thats not to say one of my pipes dont give way 2mor or the coolant channels eat the waterpump) it commutes me to work every day reckon that could be testiment has done for the last 12 months or so, i do check my pipes reg when i do my oil level and servicing, because i enjoy gettin me nose into it, reckon i may have cooked the engine before now if it were goosed in any way, i may not be a pro grease monkey but even i know when an engine is overheating, these reasons are why i've taken the precaution measures of the mason and haydn alarms because of the age of the pipes etc. I do also think i'm gettin different results from the mason alarm from you diesal guys as i'm sure you are aware my puppy is a v6er Surely the v6 temp variations will be different being a more powerfull and revving lump

[dandywarhol]

I reckon there'll be some variance in even similar engines cheffy. Cooling systems are designed to work at an optimum temperature and the system is designed around that. I don't think there'll be much difference between a Mazda 2 and a V6 but there could be a difference in the signals from the gauge sensor. Dave Mason would know more about that I think.

[Dave Mason]

... the temp gauge on my v6 with the mason stays around 11.30/12 ish can't make my mind up which ... The only time i get substantial movement on the needle is when in traffic or idling a long time when it goes 2/3 way up. I've got it on a run next month down the m/way be interesting to see what that chucks up, maybe it not compatable with the v6 Anyone else got any results on the v6 with mason, is it just a v6 thing

I reckon there'll be some variance in even similar engines cheffy. Cooling systems are designed to work at an optimum temperature and the system is designed around that. I don't think there'll be much difference between a Mazda 2 and a V6 but there could be a difference in the signals from the gauge sensor. Dave Mason would know more about that I think.

No, sorry, I really know nothing about those engines. I'm more into electronics and my vehicles are Toyotas (Townace, Yaris, both Diesel).

The temp gauge sensors in the engines are just special resistors that reduce their resistance from over 1000ohms to under 100ohms as they are heated up. Nothing complicated but the range of resistance could vary if a different spec sensor is fitted (or if it's faulty).

Apart from the audible alarm bit, the Mason alarm (and I've only ever sold one version for Bongos) also has a simple action - when the sensor resistance drops to a certain point (i.e. the engine temp goes up to a certain point) the Mason alarm switches a shunt resistance across the sensor which fools the gauge instrument into "thinking" that the engine has got a lot hotter and the sensor resistance has gone lower. The "certain point" and the value of the shunt resistance have been selected (with help from Bongo owners) so that this trick bypasses the dead zone in the middle of the gauge instrument's range and, as the engine temperature continues to rise, the pointer moves smoothly on up the dial instead of sitting near the middle, grinning at you, saying "you think your engine temperature is nice and steady but actually I'm just pretending - you haven't a clue what's going on".

So, the fact that Cheffy gets "substantial movement" in the upper half of the dial suggests that the standard Bongo Mason alarm is having the right effect in his V6 and that it has same type of sensor, and temp gauge instrument, as the others.

By the way, my summer vacations are over so there should be no delay despatching Mason alarms now. See http://www.townace.plus.com/ie/ietemga2.htm

[jaylee]

Hope you had a good break Mr Mason.
Looks like yer gonna be posting one more, i just ordered one!
Just done the Poland trip & have the constant 11 o clock reading, now occaisionaly my centre console got warm in the early miles of a 200 odd mile run then stayed relatively cool.. (even during a couple of long traffic jams!)
No loss of coolant.

With regards to over heating history;
I have a slightly opaque header tank, but i had a similar thing with a diesel Vauxhall Combo van i owned for 13 years, having been only a year old when i bought it, i had no trouble apart from the radiator bursting from some 6 or 7 years of chaffing at the back.. (a design fault rectified with a new radiator mod by vauxhall).
Lucky it was just stood idling at work at the time, & a colleague noticed water running out the bottom, so it did no other damage.
After that, it carried on to serve me well! (even though i didn't trust the temp gauge on the Vauxhall either)...

Does anyone have advice regarding fitting the alarm?
What should i be careful with?
(Apart from the thin wire thing @ the back of the temp gauge.)

[jaylee]

That was damn quick dispatch Mr Mason, just got the alarm in the post this morning!!

Cheers!!