4g93 thermostat

[pAuL]

yes this is a toyota forum but this is a non-toyota question as i dont drive a toyota currently. this afternoon i checked the thermostat becuase the fans on the raditadator seem to turn on too much, and where i thought the thermostat would be there is ... nothing!

so im wondering fi this is where the thermostat would be, i dont think it would be any other place. see picture below

[LeeRoy]

Where you have indicated doesnt look to have a buldge/flare for a thermostat to be in so it doesnt look like it should be there but if it does have a round buldge/flare then i guess thats where it could go. Check the other radiator hose and follow that to see if there is above mentioned flare thingy there.

As for radiator fan turning on if you dont have a thermostat then it will be always running colder than it should but the coolant will run hotter so im guessing that it could cause the fan to turn on more often than it should. Thermostat is designed to open and close depending on temp to keep head in desired operating range.

Btw this is a toyota forum

- LeeRoy

[pAuL]

yes this is a toyota forum but this is a non-toyota question as i dont drive a toyota currently.

i still own a toyota, and looking at getting anotother one soon.

it looks like there is enought room there for a thermostat to sit, even though its not that big. and i cant see any other place where it could be.

even sitting tonight at maccas drivethrough, about 13c outside, the fans turn on which is is worrying me. i think ill have to look into it abit more tommorow when its light.

[LeeRoy]

So that top pipe where it connects to the head has the buldge for what could be a thermostat (ie it could be the thermostat housing). On 2 of the motors i have, one has the thermostat on the bottom hose and the other is on the top (these arent mitsu motors but). Just pull it off and check for a thermostat as then youll know for sure, and even from what your describing, if it does actually have one in there its probably shagged and will need replacing anyways so your not giving yourself any more work either way.

- LeeRoy

[Dale]

i still own a toyota, and looking at getting anotother one soon.

it looks like there is enought room there for a thermostat to sit, even though its not that big. and i cant see any other place where it could be.

even sitting tonight at maccas drivethrough, about 13c outside, the fans turn on which is is worrying me. i think ill have to look into it abit more tommorow when its light.

Does your temperature gauge fluctuate at all?
The thermofans switching on when you're sitting still (ie. at a drive in as you gave an example of) is quite normal, the fans are there to pull air through the radiator while the car is stationary and/or when moving very slowly.

[pAuL]

the gauge dosnt move at all once its moved up, and yep i know its normal for them to turn on and off in near stationary situations but they seem to turn on too frequently

[Vios-GT_07]

my memory's crapping me..

but i don't think the thermostat is meant to be there.. at the top side.. it's somewhere else if i'm not mistaken.. i might be thinking of another mitsubishi motor though..

that's in the 1.8 lancer isn't it? hm.. yea i'd agree with LeeRoy.. look around the hoses and see if there's a thermostat there.. otherwise go to the auto-shop and ask for a thermostat and see what it looks like.. it could be that little space u indicated.. otherwise u have a fair indication of what to look for..

[LeeRoy]

Does your temperature gauge fluctuate at all?
The thermofans switching on when you're sitting still (ie. at a drive in as you gave an example of) is quite normal, the fans are there to pull air through the radiator while the car is stationary and/or when moving very slowly.

But even if you stop and sit for a while it takes a few minutes for said fans to turn on. From how im interpreting the above it seems as though theyre turning on every minute or so and even driving at a reasonable pace.

- LeeRoy

[Dale]

You'd have to have a good ear to hear thermos kicking in while moving at a decent pace

If there was no thermostat at all, in theory the thermofan should kick in less often, and the temp needle would likely take forever to get up to temp, maybe never get there.

That's one of the 92ish lancers with the gearbox on the drivers side isn't it? I never could figure out why mitsubishi did that lol

[Vios-GT_07]

well in practice, driving without a thermostat makes the engine run hotter... and is generally not recommended..

the fans would switch on anyway, as long as the water reaches a certain temp.. having no thermostat would surely see the water at a higher temp, but then again the fans are meant to turn on and off when the water is above or below a certain temperature respectively. it could just mean that your water temp sensor is overly sensitive, or your fans are working and working a bit too well.. but yea find that thermostat or make sure u have one

[pAuL]

dig dig dig

the thermostat usually has a pipe/going to the bottom of the radiator, not to the top, i do have one

now ive got the opposite problem lol the main radiator fan isnt turning on, but the air con works when the aircon is on, fuses look ok too
any ideas?

[Vios-GT_07]

main radiator fan?

there's the fuse, the relay, and the trigger for the relay.. since u've done the fuse, have a look at the relay that runs the fan.. and if not mistaken, the trigger for the relay is from a temperature sensor or from the ECU itself..

[pAuL]

i checked the pulg coming out of the fan, put 12v and earth straght to the connections, nothing happened, so my dad had a idea of taking it out to check the bearing, greased them up, working again now! yay

thanks for help