Where should the water temp sit?

[AlfaJack]

Hi,

On my Q4, when in traffic, the temperature reaches 93C then the fan cuts in, normal. But when driving on the motorway etc, the temp sits at about 70C, is this right or do I need a new thermostat?

Thanks
Jack

[cuore_sportivo_155]

sounds about right, no 2 thermostats are created equal :)

[wrinx]

Nope, new thermostat needed, engine temperature should always be 90 when warm...even when moving. Any difference when moving points to knackered thermostat (low) or radiator (high) or even wilder fluctuations means water pump.

Changed the thermostat and radiator on the 155 V6 and it's ROCK solid at 90 now.

wrinx

[cuore_sportivo_155]

I changed a thermostat too, and the temp went up to 75 from about 60... but no higher, unless in a traffic jam. twas a 4 cylinder though. the 145 is rocksolid at 75 also

[AlfaJack]

As I have a new(ish) water pump then I may have to take the plunge and change the stat.

Any one else know their temps when on the move?

Thanks

[arjunior45]

in a hot day {28 Celcious} in the city I had 90 - 93 degrees all the time.
Maybe a couple of degrees less in the hay-way.

Cheers

Nick

[Brul(tm)]

I always have it just below 90C while driving.
During traffic the temperature clims quickly and the fan runs quite a lot.

Greetings,
Marc

[q4fatboy]

Mine stays pretty constant at 90 ish, in traffice you here the fan kick in but the temp stays the same.

Only one thing I have noticed is the fan kicks in often and only then for very short time periods. It as if it wants the temperature as constant as possible.

[pavs]

Since I changed the Rad it stays at around 75 but in traffic up to and just above 90ish

[AlfaJack]

Now I wonder what is correct :? I will have a look in the manual and see if there is any guidance :D

[cuore_sportivo_155]

there are so many factors influencing coolant temp, it's almost impossible to tell if a stat is out. However:

- does the temp rise quickly after the engine is started? After about 5-6 km the coolant should reach operating temp.

- When stats go they tend to stay in a fixed position, usually open or partly open, so start the engine and as soon as the engine temp rises (say 50 or 60c) go feel the big hose leading to the radiator. This should still be cold. shouldn't get warm until the coolant reaches seventy (in your case)

- how accurate is your temp gauge?

[AlfaJack]

there are so many factors influencing coolant temp, it's almost impossible to tell if a stat is out. However:

- does the temp rise quickly after the engine is started? After about 5-6 km the coolant should reach operating temp.

- When stats go they tend to stay in a fixed position, usually open or partly open, so start the engine and as soon as the engine temp rises (say 50 or 60c) go feel the big hose leading to the radiator. This should still be cold. shouldn't get warm until the coolant reaches seventy (in your case)

- how accurate is your temp gauge?


Thanks CS, I will check these things out :)

[Juan AR155Q4]

I have changed my fan switch for one of Fiat Tipo. It´s an 87ºC-90ºC. So in hard traffic, never over 90ºC. In road it´s about 75ºC.

If you want to check the stat, the manual specifies a procedure to test it. Just put it in water, rise temp, and check temp and displacement. You´ll certainly know if it´s working.

[wrinx]

Since I changed the Rad it stays at around 75 but in traffic up to and just above 90ish

New thermostat needed :(

wrinx

[AlfaJack]

Do you think there might be a group buy discount from Alfa? :roll:

Yeah right! :lol:

[gtvracing]

The thermostat on a 155 Q4 will open at 82C, the fan will start at 92C on low speed and at high speed at 97C on models with Automatic Klima, after 10 seconds on low speed it sould always go to high speed, again only on models with auto klima.

[wrinx]

Sounds about right, I wasn't aware of the stat opening temp but 92 is usual for the fan.

Engines should go through 82 degrees, open the stat and sit at 90-ish ALL the time.

Less than this means your stat is knackered....or problem with the guage but that's rare.

Jack...I'll join you in the group buy :roll: :lol:

wrinx

[cuore_sportivo_155]

check the ntc for the temp gauge first, especially if you don't have any of the other symptoms of a failing stat (long time to reach operating temp and unstable at keeing temperature). wouldn't cost more than a bit of coolant to check it, if someone can share some ohm values from a maintenance manul...