1979-1993 & 94 Conv [Subscribe to Daily Digest] |
![]() | [Main C900 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Switch use Posted by Ari [Email] ![]() ![]() In Reply to: Re: 82-deg thermoswitch, Sandy '92TC, Wed, 6 Jul 2005 12:29:50 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The switch controls when the fan comes on. It's important to remember that the switch goes on when the RADIATOR is hot. Small but important distinction.
The thermostat pushes hot coolant to the radiator when the engine gets hot. If you have a 89C thermoSTAT, that's at 89C. In general, if you're going to change one (thermostat or thermoswitch), it makes sense to switch BOTH.
Remember the use of the radiator fan - it comes on to provide airflow over the radiator when there otherwise isn't any. At 55 mph, you're getting plenty of airflow - more than the fan can provide. The fan is there when you're stuck in traffic, and the radiator gets hot because there is no airflow. But if the radiator fan comes on at 89C, it blows air over the radiator until the rad gets somewhere below 89C. So it really doesn't keep the engine much cooler, 89 or 82. All the 82 does is turn the fan on sooner.
Upside? You get a little more 'headroom' before overheating. It's a good thing. Downside? Two, and they are pretty minor. The first is that the engine runs a little cooler. The engine was designed to run at 89C; at 82, it's running slightly less efficiently. We can argue for a while, but the difference is so minor as to not count. The other is that if you go to a 82C thermoSTAT, you'll get less heat in the winter. How much? Well, if you live where it gets really cold, like around 0 degrees, you may not get as much heat as you want. Maybe. But if it regularly doesn't get that cold, you'll never notice the difference. So if you live in Manitoba, I wouldn't recommend an 82C thermostat.
posted by 192.249....
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |