Temp fans come on?

[nikp]

Ok, I\'ve done a search, as i know it\'s out there, but can\'t find it for the life of me!

I\'ve just fixed my after market water temperature gauge, and therefore want to confirm everything is operating as it should.

So, i\'d like to know some coolant temps people experience. Like, when do fans usually come on? What are normal sort of running temps? What do peoples temps run at in heavy traffic in summer weather like we\'re having at the mo? Any other things i should know about temperature?

Cheers!

[Donato]

fans - 93 or 94 degrees

running temps vary car to car but mine run at 83-86 normal. 86-95 town.

83-98 foot down on track  

[nikp]

Cheers!

Hmmm....wierd in that case. My temp ran at a tad over 100 this morning. Admittedly it was pretty stop/start traffic and quite hot air temp too. Temp came down too once free of traffic, so i wasn\'t overly concerned. I have not had any issue with water loss recently, except for a small amount a couple of weeks ago.

So it sounds like my temps were a little high, but everything worked as you\'d expect. Perhaps i should keep an eye on it over the next few weeks!

[Spotlamp]

Mine are pretty much the same as Donato\'s.  I usually switch air-con on at around the 90 mark to keep it super cool.  Never seen temps in the 100s, but never let it get that far.  Was thinking just the other day I\'m going to drive around without air con on and see what happens with the temps.  In this weather though, I suspect they\'ll be fairly high!

H

[davegttph1]

Ive seen 109oC on the PFC before but there was some foot to the floor action.... average is it gets to about 90oC then I switch on the air con and bring it down to about 83-85 average. if I dont switch on the AC it\'ll rise to 99 at least in traffic.

its the ACT Im more worried about stay cool until I put my foot down even for a 10second blast then its up to 50degrees and takes FOREVER to go back down

[nikp]

So it seems before temps get high, many people stick their air con on to reduce temperatures! So not many people really know what temps. their cars will hit in traffic in hot weather!!

I have been thinking about this theory that hot coolant temps are bad. Now why is that? The fans were designed to come on at a specific temperature by mazda, and therefore they do. Is it because there\'s the thought that if it gets too hot it\'ll need a rebuild? But why? As far as I can work out there are three reasons why a rotary will need a rebuild:

1. Knock - Too much knock and Apex seal failre will occur. Many reasons why this can happen.
2. Water seal failure - usually fails due old age.
3. Overheating - Similar to overheating on a standard internal combustion engine. Warps metal, and thusly rotor housing will not mate together properly.

Therefore, as long as temps come back down when the fans come on then there shouldn\'t be anything to worry about. Of course, you only know when the fans are not coming on when it\'s got too hot, and chances are, it\'s too late by that point!

Reasonable? Are people sticking their Air Con on just as a safety buffer?

[davegttph1]

I use it as a safety barrier as if I dont stick the AC on the temps just seem to get what I consider to be too hot, anything over 100oC is too much IMO... so a nice temp of 80\'s is better. especially knowing that cooler engine = more power too

Problem is once it hits 100 degrees the metal is hot, you might be able to cool the water a little bit down to say 90 but it\'ll take a bit longer to get the engine/metal etc cooler. also not knowing these engines very well but Im presuming higher coolant temps = higher oil temps?

[nikp]

I spose there\'s another option as to why mine are a bit higher: the gauge might be innaccurate! Or, mine could be accurate, and all you people on the PFC could be innaccurate! Just a thought! :p

[nikp]

cooler engine = more power too

That\'s not necassarily true actually. Most engines are designed to operate optimally at a specific temperature. Obviously that\'s not with coolant temps at 100oC, but all i\'m saying is cooler engine does not mean more power.

It does with air temps though!

[davegttph1]

yeah but I dare bet its better to be running mid 80\'s rather than 100degrees....

least I know Im able to use the power of the car whenever its called upon when running with a reasonably low temp where as if I hit 100degrees and needed/wanted to put my foot down Id be sat thinking nar its not really wise with this temperature.

If that made any sense?

[nikp]

True, sticking your foot down on the loud pedal when temperatures are hot to begin with, could mean the coolant system is going to have a lot more heat to disperse - but any well made coolant system should cope - as long as everythings in good order in the first place.

I guess a lot of our cars are quite old now, and some parts haven\'t been changed for a while. That could add to the problem!

[andrewrx7]

Oh how us standard RX owners live in blissful ignorance!    

Accurate temperatures - what are they?! Gauge at 8O\'Clock = good, gauge at 9O\'Clock = hmmmmm, gauge at 10O\'Clock = bye bye credit card.

Oh well, maybe one day I\'ll know what the car is doing!  :yes

[davegttph1]

The way I see it too is at least if I attempt to keep the temps under 90oC if I ever look at the gauge and see 100 I know instantly something is wrong so I have time to pull over and get it sorted, if Im happy with 100 degrees and dont look at the gauge for a minute or so then see 110+ it could well be too late before youve pulled over because after switching the engine off the temps will easily rise another 10degrees IMO.

[nikp]

Actually, i may be imagining it, but i think i\'ve seen somewhere the danger temperature. Like i say, i could be imagining it. I might have a look for it during my lunch break. See if i were imagining it!

[davegttph1]

I remember a post from Gurj a while back saying somethng along the lines of if the car ever hits 117oC then youve not got much hope of saving the car....