Well, it started off just replacing vacuum lines by the blower fans. I saw some corroded connections and decided to investigate. This is what I saw. What are the two ceramic looking disks? I want splice in good wire, but the deeper I dig, the more bad wire I find. The insulation is just crumbling off. Underneath is corroded copper wire. What gauge is this wire? I'm guessing 10 gauge. One is red/white, another appears to be blue/white.

Darren
'87 944S

 

look like high power resistors. They are usually used in apllications for blower fans , as you change the settings on the fan that resistor takes the rest of the power. They get extremely hot and would explain the crumblimg wire.

 

Do you think 12gauge wire would suffice?

Darren
'87 944S

 

Those are indeed the cooling fans resistors.

 

Darren, were you able to remove the plastic cover over all of this w/o tearing it up? I need to get in there and finich my vacuum hose replacement project.

 

Oh you mean the brittle plastic cover that crumbles when you look at it wrong? You have to remove the wiper arms. Mine was stuck with double-stick tape at the top edge. I was able to gently coax it off. I have to figure out how I'm going to patch the two holes in it. There is one long vacuum hose that goes from one side of the blower assembly to the other. There's a T closer to the passenger side. I took my blower resistor out while I was in there. It didnt look too bad. I blew it out with air and sanded the contact points.

I'm a little confused about the resistors. The blower fans (climate) have the long resistor block to control the fan speed inside. shiners780 said the round ceramic resistors in the image were for the cooling fans...I assume for the radiator.
Is that correct?

Darren
'87 944S

 

what would happen if thsoe suckers were to be removed alltogether...

 

those large round resistors are for the cooling fans. I bought one by mistake coupla years ago for my 924S when all I needed to fix the heater blower was a points cleaning.

 

cooling fans for the radiator, or cooling fans for the interior?

 

Radiator. The ones for the interior blower are on the blower housing.

 

i vaguely remember electronics class...

but why do the radiator fans need such large resistors (suckers that big are what, like 5 billion ohms? with infinite heat retention)

 

Vaguely?

Low ohms to dissipate high power (i.e. the power not being dissiapted by the fans). Since they're dissipating high power (heat) they need to be large so they don't burn.

 

our fans are electric right?

why is there such a power discreprency that would require the need for such resistors?

 

Because of the low and high speed operation of the fans. The fans come on at different speeds based on coolant temperature in the radiator, the thing that tells them to go to either high or low speed is the fan switch.

I always throught the resistors for the fans were under the passenger side of the dash however.

 

I managed to find wire in a little better condition going towards the passenger compartment, but still in the engine bay.
I spliced in some 10 gauge wire, but I think the original wire was 12 gauge. I verified my cooling fans worked ok.
I managed to screw up my blower fans, but that's another thread. *sigh*

Darren
'87 944S