Radiator fan

[Starter986]

Originally Posted by steved0x

>Next day checked the fan operation (car cold, engine running, AC on) and only the passenger side fan came on.

Most common cause of this is failed low speed resistor.

There are 4 relays for the fans, a high speed relay and a low speed relay for each side. Your post doesn't say if you tried both relays on the failed side. If you jumped the high speed relay and got no fan, that sounds like the fan. But if you jumped only the low speed relay, then it could be a failed resistor which is very common and the way to test would be to jump the high speed relay.

I actually have a switch on my Boxster that grounds pin 85 on the two high speed relays so I can run the fans on high when I am on track.

Here are a couple of threads with more details:
https://986forum.com/forums/diy-project-guides/61513-diy-manual-radiator-fans-control.html
https://986forum.com/forums/diy-project-guides/76140-diy-manual-radiator-fan-switch-w-oem-switch.html

Hi Steve,

Thank you for the input. Oh... I read a lot of threads. A lot. I know that I'm not the first person with a failed fan... so I rely on the seqarch feature first before turning to the forum.

I jumped all relays... just to be certain.

The driver side high speed fan, when jumped... silence.

Once I get this repaired I'm going to go the switched fan route.

That said...

Watcha think? Do I purchased used, and hopefully from a lower mileage specimen, or do I purchase that aftermarket new one for ~$65?

Thank you.

[steved0x]

Originally Posted by Starter986

I jumped all relays... just to be certain.

The driver side high speed fan, when jumped... silence.

Once I get this repaired I'm going to go the switched fan route.

That said...

Watcha think? Do I purchased used, and hopefully from a lower mileage specimen, or do I purchase that aftermarket new one for ~$65?

Thank you.

Sounds like it is the fan (as you had already figured out ) If there isn't a huge price difference I would go with new, but I have never priced them out. Both of my fans are going strong at 154,000 miles so a low mileage used one would probably last for a long time.

Adding the switch I feel really helped me, I used to just turn it on at the end of a session and I could really see the oil temp coming down, so then I got to where I just turned it on at the beginning of every track session.

My 987.2 Cayman, from what I understand, has variable speed fans that are not as easy to jumper them to run on high, so I haven't done that mod yet on the Cayman...

[Starter986]

Originally Posted by steved0x

Sounds like it is the fan (as you had already figured out ) If there isn't a huge price difference I would go with new, but I have never priced them out. Both of my fans are going strong at 154,000 miles so a low mileage used one would probably last for a long time.

Adding the switch I feel really helped me, I used to just turn it on at the end of a session and I could really see the oil temp coming down, so then I got to where I just turned it on at the beginning of every track session.

My 987.2 Cayman, from what I understand, has variable speed fans that are not as easy to jumper them to run on high, so I haven't done that mod yet on the Cayman...

Yeah... I'm leaning towards both fans.

This morning I tackled the driver side fan removal. Hooked it up to 12V... and nothing.

The passenger side fan, because it starts on high speed, is a candidate for replacement.

I found this pair: https://www.carparts.com/details/Porsche/Boxster/Replacement/Cooling_Fan_Assembly/1998/SET-RP16090001-2.html

I've read that aftermarket fans are made of less superior components... and some reports claim vibrating and wobbly. That causes me concern because I won't want to be replacing fans forever.

So I'm leaning to a pair of fans pulled from the same car and, hopefully, with reasonably low miles. Just the fans... connector and resistor attached... plug and play. I'll be posting a WTB ad soon but, in the meantime I welcome any offers for a pair of fans.

Cheers!