Low temp fan switch ( 77/82 or less)

[miro-1980]

Hi ,

I need low temperature fan switch ( 77/82 or lower) which would fit standard 131 radiator.

I have found some available in US but they do not ship to (EU) too much red tape with customs forms.

Anybody has spares or? know where to buy them ?

Miro? ?

[Thotos]

Alfa Guilia or something... It's from an older Alfa. I have one fitted to my 131 radiator and it's 82/77 degrees or there about... And I recently got a low temperature switch for my Gamma (same fitting/thread) and that was a VW fitment. I'll check details and get back to you. But you must also change your water thermostat. There's no point having a water thermostat opening at 90 degrees and a fan thermostat switching at 82 degrees. My 131 has a Ford Fiesta 76 degree thermostat in the head and my Gamma has a 78 degree Renault 5? thermostat in the top hose.?

[miro-1980]

Thotos,

Fully agree . My current thermostat is currently fully open at 79 deg.C and I will go for even lower (71 deg C as soon as it is tested in hot water.)

With the conditions or our racing here (summer only at high outside temps , also the fact that the cars is not used for sports only and for no other purpose ... for cruising I use my 124 spider). I have found that  having both at low temperature ( like 70-79 deg C ) helps the engine to remain at good temperature through the whole race.  The head temp remains at 90-100 deg. This seems to be optimal.

Your help will be appreciated.

Miro   

[Thotos]

Hello Miro,

I'm sorry but I totally forgot to look up the thermostat info as promised. Thanks for the reminder 
But it seems to me there's something wrong with your car! If you have a 70-79 degree water thermostat and good airflow over a good radiator (with fan or at high speed) your engine temperature should be a lot lower than 90-100 degrees. Such a high temperature, assuming the thermostat is working fine, would imply insufficient radiator cooling or insufficient water flow. Instead of changing your thermostats I would suggest changing your radiator and make sure you fit the largest radiator possible (131 Sport and 2000 TC Supers had larger radiators than standard cars) and ensure it's a 3-core radiator for extra cooling capacity. Since your car is used for racing, you don't want the fan running all the time and sapping engine power. At high racing speeds there should be enough airflow over the radiator without the fan. It's also worth adding "water wetter" (http://www.redlineoil.com/products_coolant.asp) to your coolant to aid the flow and reduce the temperature. 

[miro-1980]

Thotos

Thanks for the tip. I did not know about the WaterWetter. I have found that it is being marketed in Poland. I will buy and try it . Have you used it ? Anybody has any experience with it ?     

I have a feeling there is something wrong ( maybe my driving ... )

The car has always been running quite hot.

1/ The radiator was new standard 131 installed three seasons ago when the engine was put together. It is fine and should not need replacing.

2/I have checked the water sensors ( I have two : one in the head and the other in the T-piece)  they do give accurate temp reading.   

3/ Thermostat  temperature is currently rated 79 C(the 85 C was replaced) . This has not really improved the situation much, but just a noticeable bit. I am planning to go for 71 C later this month.

4/ made sure the coolant solution is strong enough and there are no air bobbles trapped in the block.

3/ I properly tuned and timed the engine (the timing was retarded and this made the problem even worse)

Finally I  changed the fan switch from 87/92C  to 77/82 C. This has really improved the situation a lot without really increasing the time the fan is on ( BTW: I have two fiat fans working sided by side. (I am actually thinking of going still lower 78/65 C.)

Note that the engine was build on extremely low tolerance of 0.03 mm with standard pistons , cranks and etc. It took me a year of driving to brake it in. Now it is normally being rev'ed up to 7600 in each gear (Typically I do not shift up until the engine has reached at least 6 K and the reaching 7600 RMP on each gear is a normal practice. On the way to the races I typically drive at 80/90 mph for hours.
So yes the car is being driven very hard. 

All of this is far from standard.

I believe that 78/65 degree fan switch would be ideal. I also believe that the very good affect of switching to 77/82 C was not related so much to better engine cooling but lowering the engine temperature overall and thus preventing all elements under the bonnet accumulating too much heat. 

Anyway. I am very interested in the low temperature switches and your assistance would be appreciated. ( I said switches because I want to do a bit of experimenting before committing to any tempo rating and I have 124 spider which has exactly the same temp problem I need to fix)

I also want to get a new radiator and the one you describe would be ideal. Anybody knows where to get a new one like this ?

Miro 

[Thotos]

Hello Miro,

I have used the "Water-Wetter" in my Lancia Gamma and it had a noticeable improvement in lowering the temperature but mainly in preventing sudden overheating which is a common problem with the Gamma due to poor water circulation. After a long high speed run, if a Gamma slows down rapidly or worse stopped and left to idle, it overheats very quickly  The water-wetter eliminated that problem.

Having lower temperature water thermostat and lower temperature fan switches will simply lower the temperature at which the cooling begins. If you have 80 degree thermostats but the engine temperature rises to over 90 degrees then the cooling capacity of the system is insufficient for your engine otherwise the engine temperature would be at the thermostat temperature. I think the type of engine you have and the type of driving your car and engine are subjected to cannot be cooled by a standard 131 radiator designed to cool a normal car under normal driving conditions. There's enough room to fit a wider radiator in a 131 if you don't have an oil cooler (in which case maybe you should fit one). Take some measurements for the largest radiator you could fit and contact Yagmur who can supply a custom built 3-core radiator. You should also consider using Kenlowe fans as they are much more efficient.

[Tas131]

I also want to get a new radiator and the one you describe would be ideal. Anybody knows where to get a new one like this ?

Miro?

G'day Miro,
I've got one in my car that was repaired, serviced and pressure tested 6 months ago. I need a smaller radiator so I have enough room beside it to mount an intercooler for my supercharger. Maybe we can work something out. If I can find the digital camera I'll post up a photo.

Cheers,

Mick.

[djape1977]

fan switch is same for any fiat of that era as well as for any lada and zastava. 68*/82* is available for yugo and zastava 128