Thermo Fan Swith replace 944 S2

[midwestshooter]

Help!

1989 944 S2.

My fans are running full time. It drained the battery overnight.

I just ordered the 85 degree thermo fan switch from Pelican. It should be here tomorrow. I hope that it's not the relay.

and now -

How do I get the connector off the old switch? I pulled on the wires but it doesn't want to come off.

And - how do I drain and then refill and bleed the coolant? I remember having this done once and there was a step where you had to let out some air.

I'm not a total clutz - but I can use some pointers and tips here.

Dick

[SoCal Driver]

You have to get the right radiator mounted temp switch for your car. The early temp switches will not work with your electrical system. Something about the $150 relay. Later temp switches have two outputs -- three prongs.

Was a write up about trouble shooting the later cooling fan system somewhere. Try www.clarks-garage.com and searching this forum.

[EMBPilot]

i would disconnect your battery, disconnect the fans, then remove the fan housing from the radiator. using the drain plug, you may only need to drain about two liters out of the system to get the coolant level below the thermo switch.

the wire clip should come off the back of the thermo switch with a gentle tug. you'll need a deep 30MM socket for the thermo switch and a new crush washer, i think it happens to the be same washer as the oil pan plug crush seal. i think the torque on the thermo switch is 28NM ?.
i just did this when i replaced my rad.

[midwestshooter]

The switch in the car has the number 851 on it - so I ordered the 85 degree swithc.

Dick

Originally posted by SoCal Driver
You have to get the right radiator mounted temp switch for your car. The early temp switches will not work with your electrical system. Something about the $150 relay. Later temp switches have two outputs -- three prongs.

Was a write up about trouble shooting the later cooling fan system somewhere. Try www.clarks-garage.com and searching this forum.

[midwestshooter]

>you'll need a deep 30MM socket for the thermo switch

Are we talking about the same part? Mine is 17mm.

Maybe I better post a photo before I remove it.

Dick

>>>>>>>>>>>>

Originally posted by EMBPilot
i would disconnect your battery, disconnect the fans, then remove the fan housing from the radiator. using the drain plug, you may only need to drain about two liters out of the system to get the coolant level below the thermo switch.

the wire clip should come off the back of the thermo switch with a gentle tug. you'll need a deep 30MM socket for the thermo switch and a new crush washer, i think it happens to the be same washer as the oil pan plug crush seal. i think the torque on the thermo switch is 28NM ?.
i just did this when i replaced my rad.

[EMBPilot]

maybe not, i thought you were talking about the switch on the radiator that plugs in on the drivers side below the hose that connects to the top of the head.