Author Topic: Radiator fan  (Read 6876 times)

sgould

  • Aerobic
  • SST paid up supporter
  • Overboost
  • *
  • Posts: 5388
  • Number of thanks: 345
  • 2006 9-5 Aero estate - Hirsched.
    • View Profile
    • Christine Bennett - soprano
Re: Radiator fan
« Reply #15 on: 27 June 2019, 12:11:50 AM »
Thermostat, not the temperature sensor.

The car relies on the radiator to cool the engine.  If the car is stationary or moving slowly, there is not enough airflow to keep the engine cool and the fans will cut in.  Once you get on the open road the airflow through the rdiator is far greater than the fans could provide and can overcool the engine.  The thermostat closes when the water cools and restricts the flow of coolant, allowing the engine to warm up again.  Your thermostat isn't closing enough.
Help support SaabTechTalk by making a Lump Sum donation or by opening a subscription. 
Options available are in your Profile/Actions.

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #16 on: 27 June 2019, 12:18:47 PM »
Hi Sgould,

If my thermostat is bad, not closing enough and the temperature sensor is good, i should be loosing coolant (or least a drop in coolant level since it is been used), assuming the info sent to the control unit which doesn't tell the thermostat to close. My understanding is both thermostat and temperature sensor are either bad or good, there's no middle ground. I eliminated the thermostat itself because i am not loosing any coolant and i making a calculated guess that the temperature sensor is sending signals that the engine is always cool, meaning the thermostart would not open, hence stuck in the closed position, no coolant released no fans would kick in and start, the reason why my temperature gauge on the dashboard never gets to 9'O clock (except in a stationary position).

Homework for all, any comments will be appreciated.

carrera

  • SaabTechTalk-Team
  • Test pilot
  • *
  • Posts: 1107
  • Number of thanks: 17
    • View Profile
Re: Radiator fan
« Reply #17 on: 27 June 2019, 01:21:07 PM »
Homework for all, any comments will be appreciated.

In the nicest possible way I think you need to do the homework. sgould explained precisely what we suspect is happening. A thermostat is a mechanical device in a car, not electrical like in a domestic heating system........ there are no wires to the ECU.

£8.40

https://www.saabits.com/all/genuine-saab-900-99-90-9000-9-3-9-5-thermostat

9-5 Aero Estates, 2002 Cosmic Blue, 2003 Steel Grey, 2003 Graphite Green, 2004 9-5 Glacier Blue 2.0 saloon, 2004 Nocturne Blue 2.2 diesel estate, 2006 & 2008 Black Aero saloons, 1998 9000 CSE with Aero engine, 9-5 NG Aero XWD Turbo4, 9-5 NG Aero XWD TTiD

sgould

  • Aerobic
  • SST paid up supporter
  • Overboost
  • *
  • Posts: 5388
  • Number of thanks: 345
  • 2006 9-5 Aero estate - Hirsched.
    • View Profile
    • Christine Bennett - soprano
Re: Radiator fan
« Reply #18 on: 27 June 2019, 01:43:31 PM »
The thermostat on the diesel comes complete with the housing to connect to the pipework. Item 1.  The temp sensor screws into it.

The current part number is 55203388

The sensor is item 2.
Help support SaabTechTalk by making a Lump Sum donation or by opening a subscription. 
Options available are in your Profile/Actions.

carrera

  • SaabTechTalk-Team
  • Test pilot
  • *
  • Posts: 1107
  • Number of thanks: 17
    • View Profile
Re: Radiator fan
« Reply #19 on: 27 June 2019, 01:56:08 PM »
 :)  ...... I hardly ever think diesel  ;), engineering principles are the same though, not available from Saabits website direct then 
9-5 Aero Estates, 2002 Cosmic Blue, 2003 Steel Grey, 2003 Graphite Green, 2004 9-5 Glacier Blue 2.0 saloon, 2004 Nocturne Blue 2.2 diesel estate, 2006 & 2008 Black Aero saloons, 1998 9000 CSE with Aero engine, 9-5 NG Aero XWD Turbo4, 9-5 NG Aero XWD TTiD

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #20 on: 27 June 2019, 02:43:36 PM »
The thermostat on the diesel comes complete with the housing to connect to the pipework. Item 1.  The temp sensor screws into it.

The current part number is 55203388

The sensor is item 2.

Nice one Sgould, on point again, you must be a Saab pro, thanks for the pix.

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #21 on: 27 June 2019, 02:46:41 PM »
Homework for all, any comments will be appreciated.

In the nicest possible way I think you need to do the homework. sgould explained precisely what we suspect is happening. A thermostat is a mechanical device in a car, not electrical like in a domestic heating system........ there are no wires to the ECU.

£8.40

https://www.saabits.com/all/genuine-saab-900-99-90-9000-9-3-9-5-thermostat



Thanks Petrol head Carrera, he he he...

sgould

  • Aerobic
  • SST paid up supporter
  • Overboost
  • *
  • Posts: 5388
  • Number of thanks: 345
  • 2006 9-5 Aero estate - Hirsched.
    • View Profile
    • Christine Bennett - soprano
Re: Radiator fan
« Reply #22 on: 27 June 2019, 04:41:19 PM »
I'm not a pro.  I'm just a retired old bloke with time on his hands... :D
Help support SaabTechTalk by making a Lump Sum donation or by opening a subscription. 
Options available are in your Profile/Actions.

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #23 on: 25 July 2019, 11:56:21 AM »
Car booked in for new thermostat and cam-belt change + water pump, not sure when the last owner changed cam-belt, so better safe than sorry.

Is there any improvement in performance should expect?

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #24 on: 12 August 2019, 07:24:30 PM »
it should be at 9 steady,shouldn't drop..the coolant temp is used by the ecu to adjust the amount of fuel,cooler engine=more fuel used..

Hi Aerojon, got my thermostat replaced last weekend along with the timing belt and water pump, car smoother to drive but the fan still doesn't kick in, drove an hour from work, got home opened the bonnet, fan is not turning, temperature gauge is steady at 9 o clock.

Could there be something wrong with the fuse? The fan only works when the ac is switched on.

sgould

  • Aerobic
  • SST paid up supporter
  • Overboost
  • *
  • Posts: 5388
  • Number of thanks: 345
  • 2006 9-5 Aero estate - Hirsched.
    • View Profile
    • Christine Bennett - soprano
Re: Radiator fan
« Reply #25 on: 12 August 2019, 07:28:06 PM »
Could be that the engine temp is not getting high enough to need the fan?  Diesels do run less hot than petrol engines.
Help support SaabTechTalk by making a Lump Sum donation or by opening a subscription. 
Options available are in your Profile/Actions.

Mrqng78

  • Linear
  • *
  • Posts: 65
  • Number of thanks: 0
  • Saab 93 linear.
    • View Profile
Re: Radiator fan
« Reply #26 on: 12 August 2019, 09:36:12 PM »
I'll keep an eye on it all week to see how it behaves.