Yessir, exactly my point!

And FWIW in reference to Michael, my aforementioned post was not contradicting anything about a broken wheel on the assembly ...if it's broken, the wheel will be missing! I would count that as an obvious "yeah, sumptin's wrong here" moment. I was simply pointing to the possibility that all may look ok and the switch is bad...this you cannot see. And that is precisely what happened in my experience many moons ago ...which is why I wrote what I did. We're not really trifling over minutia, are we?

Replace the assembly: easy. And like I said, the wear on your belts is a wholly separate point ...but heck, this may be a good time to check your records and/or belts if you're already in there. But if the belts are fine, just do the sensor and you'll be in/out in 5 minutes ...ok, ok, 9 minutes if you really take your time

Edward

 

Anyone have the part # for the switch?
Thanks!

 

If your car has a separate belt for the fan and another for the alternator (not true with the RS pulley... then you just have a single belt for both), you should not bypass the fan sensor... you will have no other way to know if your fan belt is broken and could lead to a catastrophic engine failure. John D... this means you! The alternator belt (hence the RS pulley system) will give you lots of warnings when it fails... all of your warning lights will come on until the engine just quits from lack of battery power. Hopefully a simple replacement of that sensor will fix the problem reported by the O.P.

 

I know you are RIGHT - but, in my defense....

Over the past 40 years of daily driving my 911s - here is my take...

My '64, '65' 68, '71, '73, '77, '78, '82' '87, '88

My 911s all lived without a sensor to tell me when the belts were about to let go... Of course, I did/do have my head in the engine compartment on a frequent basis, as these were/are daily drivers 365 days a year (except on leap year - which added another day )

And - oh - as I disconnected it on my '95 - I guess I should add that to the list above..

As well, if I EVER sell my 993, I'll probably replace the sensor/switch? Why? I don't expect the next owner to have their eyes in the engine compartment as often as I do..



Best to you!

John

 

John, John, John,

Didn't all those early 911s come with just a single belt that drove both the fan and the alternator? Kinda like the RS pulley upgrade for the 993s? No sensor needed for a single belt system.

 

I know, I know..... You are - of course - RIGHT!!

OK - what ca993twin said.... Replace the switch/pulley system.... And I'll replace mine... It really should be done correctly...

(Walking away dejected and shamed ) But, rightfully so - as without the RS pulley system, YES - you are putting the engine at risk....

John

 

Thanks guys. I disconnected the sensor and reconnected it and everything seems to be fine for the moment...but I plan to check back regularly and will replace the belts this coming winter. I will probably also replace the sensor at the same time!

 

I checked my sensor wheel with the aid of a mirror and light and thought it was fine. When I took it off I found a small crack that I could see right through! The bearing was fine.
Worth changing the little bugger before the fan chops it up.
993-106-035-00

 

The very thing happened to me this weekend while I was up in Vancouver for MikeJ's BBQ. It seemed to be very intermittent. The belts looked fine and the sensor wheel was doing it's thing running a slight groove in the back of the belt. Pulled the connector plug on and off a couple of times to clean the connections and didn't see the warning lights for the 140 mile drive home last night. If the switch gives me anymore problems, I'll just replace it.

 

Get this from sunset porsche. It is cheaper than I have seen it somewhere else and OEM. Just get a set of belts with it and replace them, too. Good insurance

 

My warning light reappeared after a 250 mile drive....came on 2 miles from home I just received my new belt tension sensor and will throw it on along with new belts this weekend.

 

My wheel and belts all check out fine. Can someone walk me through testing the sensor with a multi-meter. I'm not very bright when it comes to electrical circuitry, and I hate to order a sensor if it's something else.

 

The belt sensor is a black plastic circle a little bigger than a quarter surrounding a metal smaller one. The plastic broke on mine, allowing the sensor to move just enough to trigger, but all looked good until I looked up in the PET and saw the disk looked quite a bit bigger.

Maybe that's it.

 

Becker135, the belt sensor microswitch is normally open, in other words, when the tensioner senses the belt, there's no light on. When/if the belt breaks, the tensioner microswitch closes and the light goes on. With a VOM set to Ohms across the two microswitch contacts, you should have no continuity when the switch is open and 0 ohms when closed.

 

I know this is an ancient thread but it saved me from some serious anxiety as I was about 20 miles down Skyline on the way to Santa Cruz (40 miles from home) and my fan belt warning light went on. A quick search and my mind was put to ease. New sensor is on the way as well as new belts for added insurance. So glad to have this forum and all of the people that contribute what seams to be boundless knowledge. Cheers to Rennlist!