Darien

I noticed a sqeal and grinding sound coming from my Fan Pulley area last night. I removed it this morning and discovered a bearing gone bad. I just ordered a new one, but this is my daily driver. I was told that the electric fan comes on when I turn on the AC. I just checked and the elec fan is not coming on with the AC.

Does anyone know the operation of the elec fan? I tried to check for a fuse, but I don't know which one it is!

Need help on this one!!

Garth S

#29 @ 25 amp
Pull down the fuse/relay chart (left panel) https://www.928gt.com/default1.htm and copy for the glovebox.

Darien

Thanks Garth!!

So the fan should operate with the AC?

D

Jim bailey - 928 International

The electric fan should come on when the coolant temp hits the upper white line triggered by a thermal switch in the lower left front of the radiator and by a thermo switch on the receiver dryer when the system builds up some heat . Your year the fan does not come on immediatly when the a/c is engaged it takes a while for heat to build up.

Darien

Jim,

Just the info I was looking for. I'll check it after I drive it to work.

Thanks

Jim bailey - 928 International

The car will not overheat unless you get stuck in really bad traffic you could drive to L A no problems until you hit grid lock !!

Sharks

Jim, I have a 86.5 too and was thinking about removing the engine driven fan and the small electric pusher fan, and installing one large electric pusher fan in front of the condenser. If I tap into the existing electrical for the small electric pusher fan will the fan operate as you state above (with water temp and/or A/C on)?

Jim bailey - 928 International

The pusher fan really only cools part of the radiator a rear puller in the shroud makes air move through all the radiator. But many are using the switches to trigger a relay to run after market fan/fans. There are also aftermarket adustable thermo switches to have more control all the hotrod catalogues carry them.

Sharks

Thanks Jim, I am try to determine if I can fit a puller with a Supercharger or if I have to switch the blades to make it into a pusher.

Darien

Well, the elec fan doesn't seem to be working I'll t-shoot that tomorrow! Anyone have some experience dealing with an inop elec fan (86)?

Garth S

If you doubt the fan, start by opening the connector to the fan: Grab some wire and ground the brown side - and use a fused jumper from the 'jump' start terminal to get +12v to bump the motor. It should start with a finger chopping roar!
If it passes this test, and all appendages are intact, move on to the thermo switch in the rad (lower front left - your right facing the car) . Check that the wires are in good contact. IIRC, the supply to this is unswitched 12v, so jumpering here should start the fan. Actually, I would start at this point, as the fans rarely die ( spin the blades with something other than a finger, and if they spin freely the fan should be fine).

WallyP

Darien,

Before you start getting too deep into the fan problem, one correction - the only unswitched power source for the electric fan on your '86 is for the plenum overheat switch on top of the intake. All other fan power sources are switched - that is, the ignition switch must be on before the fan will run.

There are several possible causes for the fan not running, and a faulty fan motor is not the most likely.

To test the fan:
-Pull the connector from the stem on the A/C receiver/dryer and jumper the connectors in the harness plug.
- Turn the ignition switch on. The fan should run.
- If the fan does not run, check fuse #29.
- If the fuse is OK, pull Relay XVIII and check for 12 vdc on terminal 30 in the socket (from fuse #29). If there is power here, jumper terminals 30 and 87 in the relay socket. The fan should run. If so, the relay is probably faulty.
- If the fan doesn't run with the relay jumpered, pull the connector on the fan motor and check for 12 vdc on the red wire. If there is 12 vdc on the red wire, check for a faulty ground on the brown wire.
- If the fan does not run with 12 vdc on the red wire and ground on the brown wire, the fan motor is faulty.

Pizza

Once you get the electric pusher fan working I think you will be OK without the pulley driven fan for a while. I deleted my smog pump and took my pulley fan off too. I have been running it like that for over a year now and my temp gauge never goes over the top white line. My electric pusher fan comes on before it even gets close to the white line and cools things off quickly. Eventually I will install a electric puller fan in the shroud when I SC my car. Good luck.

Darien

Just curious if this is the connector from the stem on the A/C receiver/dryer that I'm supposed to jump to?

http://forums.rennlist.com/upload/mvc003f_copy13.jpg

Darien

I started with the fuse and relay, they checked good, so I jumped terminals 30 to 87 and the fan worked. I'm guessing the thermo switch or the wiring that runs from it is the problem.

Again this is my daily driver, anyone know if I can jump from another relay that operates with ignition on and has switch in the car? That would work until I can narrow down my the problem.