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Bellamachinna · Posted: Mon Sep 06, 2004 5:11 pm Post subject: Water Temperature

Hi...

Yesterday, my 16v scared me...I was driving in town(Lisbon), and then i noticed that the temperature gauge was very hot...(3/4 and a bit more on the hottest part of the gauge). The fan was working, but it seemed that it didn´t did anything to reduce heat...(All this during Stop/go traffic lights action). On Autoestrada (highway) the temperature decreased to 80ºCels.(The middle of the gauge), but that driving with care-if i pressed the acelerator the temp would rise again... Crying or Very sad

Im i looking at thermostat failure, or water pump failure???
I had several other 33´s, but this one seems to run a bit hotter than the other´s...I remember that on a 1.5 TI the neddle got to the middle of the gauge, and as soon as it passed that mark, the fan started working... Cool

This 16v always went till the 100ºCels., but on the move it would drop to 60ºCels. (+/-)... Confused

What do you think on this???
Help....
Please.
Paulo Camilo
Boxer 16v QV (with hot blood) Sad

paddy granger · Alfa Sprint Joined: 12 Aug 2003 Posts: 248

60 degrees celius seems too low to me, perhaps the temperature gauge is faulty?? On the 8v boxer engine, the fan kicks in at about 90 degrees, and the temperature stays constant. On the motorway, I would expect about 80 degrees, depending on speed obvioussly (somebody may have to correct me).

But 60 is far too low. Confused

gritsop · Posted: Mon Sep 06, 2004 8:48 pm Post subject:

Hi,

100 degrees in a traffic jam is the upper limit that the engine can run - in this situation the fan in always working in order to keep the temp from 95-100 degrees.

60 degrees is far too low for normal temperature. I would suggest to replace your thermostat and then if nothing changes the next suspects are the radiator (clogged or rusted inside) and the water pump.

If dirt exists in the cooling system then the water pump has a hard time since the bearings it has are corroded and leaks will eventually start.

Hope this helps - feel free to ask more if needed.

Regards,
_________________
Thanassis Gritsopoulos
1991 Alfa 33 1.4 IE
2001 Alfa 147 1.6 Distinctive

http://www.alfa-restoration.co.uk
Parts Shop: www.alfa-restoration.co.uk/shop

paddy granger · Alfa Sprint Joined: 12 Aug 2003 Posts: 248

I suggest that you flush the system, and change thermostat. The thermostat must be sticking in order to obtain these temperatures.

Laki · Alfasud Joined: 06 Sep 2004 Posts: 74 Location: Ljubjana

thermostat is the most likely problem....Flushin is not necessery but changing it should not cost you more than around 30€ . So do changed it quickly.
_________________
-- ALFA ROMEO 33 Q4 --

Paul D. · Guest

The fan also is activated by a temperature switch, you can buy other sensors that switch the current to your fan at earlier temperatures so it doesn't raise that much in hot slow traffic. I know, it's not ideal to take a stress-test at that moment when you see the gauge going...

Regards!

Paul D.

Eddie W · Posted: Tue Sep 07, 2004 11:46 pm Post subject:

The thermostats are designed to fail open so a problem in this area is highly unlikely to cause overheating. I believe there may be different temp ranges for the fan switch to suit different climates and logic suggests the same for thermostats although our parts suppliers in NZ don't seem to take this in to consideration as there is a distinct variation in the switches I have bought( tested in hot water with thermometer).
I have dismantled the end tanks off a couple of rads. lately and there has been quite a lot of clogging in the section of core below the pickup pipe which suggests a design flaw to me. I would suggest as a first step to get the tanks removed and core cleaned by a specialist and then look to the water pump.
Regards Eddie
_________________
A LITTLE FURTHER A LITTLE FASTER

Laki · Alfasud Joined: 06 Sep 2004 Posts: 74 Location: Ljubjana

I think that Renault 4 GTL thermal switch starts the fan at around 82C that is the best one I have found. You will have to change connecotrs a bit but I belive it is worth it...Normaly I think it start with serial ones at 87C
_________________
-- ALFA ROMEO 33 Q4 --

Ken McCarthy · Posted: Thu Sep 09, 2004 1:26 am Post subject: Water Temperature

Fan thermal switch for the 33 closes contacts at 93 degrees C and opens about 83 degrees C according to a few I have tested. The thermal switch from an Alfetta switches at 85/75 and is a simple replacement. However, Series 3 Alfa 33s have the thermal switch mounted on the inlet side of the radiator while older cars have it on the outlet side of the radiator so if you fit a colder switch to a Series 3 your fan will probably run continuously. I don't know why the change but I suspect it is to keep a more constant and higher temperature for emissions and fuel efficiency.

Although I have a Series 3 16V engine, I still have the Sprint radiator. I have fitted the cooler fan switch but I have also removed both the thermostat and mechanical water pump, replacing them with a sensor for a variable speed controller and an electric water pump. The whole system has been tuned to control around 85 degrees C and does it well + or - 5 degrees. Electrics have been set up to run the electric water pump with the fans (I have 2) if the fan switch keeps the fans running after the engine is turned off on hot days or following a heavy right foot session.

Regards
_________________
Ken McCarthy - 16V Sprint

Bellamachinna · Posted: Fri Sep 10, 2004 5:13 pm Post subject: Water temperature

Hi all...
Thanks for all your replies. The problem is "solved".
I changed the thermostat, and now it is back to his normal working temperature...( 100ºcels., and on motorway it drops back to 60ºcels.).
However i still think that the top temp. is to high, and the 60ºcels. on motorway, to low....
Solving the 100ºcels, is easy-Got to change the fan thermal switch...
But how do i keep it warmer on motorway??
I also checked the resistance value of the gauge sender, and its OK, so the gauge readings should be correct...

Thanks one more time
Paulo Camilo

paddy granger · Alfa Sprint Joined: 12 Aug 2003 Posts: 248

Sergio · Posted: Sun Sep 19, 2004 12:19 am Post subject:

60ºC is way too low a temperature for a new thermostat... I've changed mine this week and it maintains the temp around 80-82º.... it will rise to the 90s before the fan cuts in... but other than that she is behaving her self...

Did you use a new thermostat or a used one? (just asking Very Happy

)

all the best

Sérgio

paddy granger · Alfa Sprint Joined: 12 Aug 2003 Posts: 248

Sergio · Posted: Mon Sep 20, 2004 7:18 pm Post subject:

good point Paddy... sorry I didn't see your post

all the best

Sérgio