Fan switch related to overheating?

[amehl]

I have done some searching and it seems like a pretty common issue on the 84s.

I just got done with my TB/WP service (put in a new thermostat obviously) but I still have the same fan issue.

the fan works, but it comes on late. Like, the temp is almost on the yellow before the fan kicks on. As a temporary fix I just drive with the AC fan on when its hot and the temp stays perfect.

would the fan switch be the next thing to replace? I already have the "low-temp" switch, but I havent installed it yet.

Or is there something else I should be looking at?

[v2rocket_aka944]

sure sounds like a switch problem.
i have the low-temp switch and i never get to the middle of the range...ever. even going uphill with AC on in 100* heat.

[mytrplseven]

the fan switch should match the thermostat temp rating. Regardless, a lower fan temp rating should make the fan come on at a lower temp.

[pfarah]

Exactly!
I had the same issue until I installed the lower temp switch then Bingo!!

[amehl]

Great! good to hear. had to order a socket for it but it will be in soon. Thanks!

[flash968]

makes me nuts where they put the fan switch on the 968. you really can't get to it without removing the fans themselves. on top of that, they put it right below the upper hose. yeah - coolant dripping on an electrical part is NEVER going to cause problems. just crazy

[amehl]

Originally Posted by flash968

makes me nuts where they put the fan switch on the 968. you really can't get to it without removing the fans themselves. on top of that, they put it right below the upper hose. yeah - coolant dripping on an electrical part is NEVER going to cause problems. just crazy

Yeah mine seems accessible. I shouldnt have to remove the hose. I think I can get it by just popping the lights up, and I may have to remove the airbox.

Seems simple enough (famous last words). This is my first porsche so I am learning as I go.

[v2rocket_aka944]

Originally Posted by flash968

makes me nuts where they put the fan switch on the 968. you really can't get to it without removing the fans themselves. on top of that, they put it right below the upper hose. yeah - coolant dripping on an electrical part is NEVER going to cause problems. just crazy

when they were designing it, they probably were thinking "who needs a radiator"?

[flash968]

i can reach the switch just fine. can't get a tool on it though without removing the fans.

[sausagehacker]

On the NA you don't even need to pop up the lights. I take the fans off to give myself more room though... it takes 3 minutes.

[pfarah]

I also removed the fans prior to switch replacement. It permits one to properly torque the switch.

Plastic threads: 20 Nm = 14.75 ft/lbs
Brass threads: 28 Nm = 20.65 ft/lbs

Important: Please make sure you replace the fiber ring seal!

[flash968]

re: seal - no kidding! sure fire way to have a leak is to try to reuse it

re: torque - very important to not over-torque. old radiators are rather brittle. i'd hate to see it crack because of trying to skip a step

[pfarah]

Hey, some guys get lazy... just sayin'.
As for the torquing process, I try to correctly torque everything whenever possible... Those nice T wrenches sure come in handy. Speaking of T wrenches, I purchased a Husky 1/4" drive unit from Home Depot a couple years ago and it actually came with a Calibration Certificate! The wrench was tested at a local calibration facility (just to be sure) and the readings were spot on. I then purchased their 3/8" with similar results, ended up saving a few hundred dollars over the truck brands (I do own a Snap-On 1/2" drive wrench) while achieving accurate results.

[amehl]

Update: able to do it without removing the fan shroud. It was tight, but the shroud flexes just enough to get the socket on. I did remove the top of the airbox. Baby is running cold as ice now! Thanks all!!!

[amehl]

Just one more thing. Both fans come in at the same time. Correct?

[Gawernator]

The new part should come with the seal