OK, yet another 308 cooling thread here..... It looks like only one of my twin cooling fans is coming on when the water temp starts to get hot. Car is a 1982 308gtsi. I'm wondering if anyone knows: 1. Do both fans come on at the same temp? 2. If no, are there two separate temp switches? Location of each? 3. Is each fan separately fused and relayed?? Any help is much appreciated - thanks!
1. Yes, a common thermoswitch in the radiator bottom tank controls both relays running the radiator fans. 2. N/A 3. Yes, there are separate relays and fuses for each radiator fan motor.
I am having much the same trouble with MY 82 308gtsi! When it gets warm, (mostly with the AC on) only one fan was coming on. Unfortunately, it appears that fan is dead. Its siezed up. I just started another thread regarding details on CFM rating, diameter of fans, etc. in my research on aftermarket replacements. Good luck on yours!
But I think, if you're not up to the temp yet and you turn the AC on, only one fan will come on until it reaches a certain temp (185 to 190F) then both will come on.
A good place to start is to short the thermoswitch in the radiator. It is at the bottom of the radiator below the bleed valve. You can do this when the car is cold and not get burned! Turn the ignition on (dont start the motor) and short the switch. Both fans should come on. If not then you will need to track down where power is not making it to the fans. Sometimes the connection inside the fan is faulty and wiggling the wires at the fans can cause them to start working (probably temporarily though). Aaron
Sounds like you don't have a wiring diagram. hint hint The AC switch will turn on one fan. The thermo switch turns one both fans. Simultaneously. Fans are controlled by relays. If even one fan comes on with high temperature, your thermstatic switch is ok. Next step is to apply 12v directly to the non-operating fan to see if it's the fan or the circuit which is the reason why it doesn't operate normally. __________________________ http://www.ferrari308gtbi.com/
Much appreciated fellas - great tips here on how to diagnose it more efficiently/effectively. I'll spend some time running the tests and checking various connections/continuity over the long weekend and report back. Again, thank you!
Quick update here - the fan itself was toast. To be more specific, the LH fan (stock factory fan) had eaten its brushes to the nub. I ordered some new brushes for $10 and she'll be good as new in no time. Incidentally, here's a good rebuld pictorial (yes, Panteras have the same fan motor as 308s). http://www.panteraplace.com/page115.htm Thanks again!
I took my time on this and cleaned up and rebuilt the LH fan - new bushings, larger power feed leads, cleaning, lubricate the clearance bearings, refinish the commuter surfaces, etc. The rebuilt fan runs MUCH better than the other non-rebuilt fan - a LOT more air movement and much quieter. My personal formula for 308 cooling issues is: 1. clean/rebuild your cooling fans, 2. new 1.1 bar pressure cap, 3. new thermostat, 4. flush coolant, 5. check/clean radiator, 6. fill and bleed the system. If you do the above I think you'll eliminate 90% of cooling issues. The cooling system, as designed, is pretty effective. The problem is that time takes its toll on cap/thermostat springs, fan wiring, fan internals, rad passages, etc. Fix these things and your 308 should be fine in all but the hottest Phoenix 120 degree summer days.
