Radiator fan

[Starter986]

Took a drive to Big Bear last weekend, and the car was running a little hot. I have Torque on a tablet and was monitoring the coolant temperature. It does put the dash gauge to shame. Anyhow... driving up the backside the temperature was reading 230+. When I was on the straights it dropped. The coolant light never came on.

Next day checked the fan operation (car cold, engine running, AC on) and only the passenger side fan came on. OK. So I ran the tests (relays "clicked"... swapped relays) and no driver side fan. Removed all relays and jumped them. The passenger side passed. Driver side... nothing. So I'm leaning towards a failed fan.

Correct me if I'm wrong: Jumping the relays with no fan action reveals a failed fan. Isn't jumping the relays to see if the fan works the same as disconnecting the fan harness and testing at the actual fan?

There are fans for sale on EB, and with the resistor attached. They're running ~$60 shipping included. I found this fan:https://www.carparts.com/cooling-fan-assembly/replacement/rp16090001

With shipping... ~$65.

Assuming I've no more tests to run... do I buy used or the new unit?

If I am buying a unit, new or used, I'd open to purchasing from a forum member same terms.

Thank you for your consideration.

[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

[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!

[piper6909]

Did you pull the plug at the fan and check with a test light to see if there's power at any of the pins? I'd make sure I have power at the fan before buying another one.

[Starter986]

Originally Posted by piper6909

Did you pull the plug at the fan and check with a test light to see if there's power at any of the pins? I'd make sure I have power at the fan before buying another one.

I did not. Can you point me to the instructions for that procedure? Is that something that can be donw without removing the bumper cover or the wheel well plastic?

Thanks, Pipe.

[piper6909]

Originally Posted by Starter986

I did not. Can you point me to the instructions for that procedure? Is that something that can be donw without removing the bumper cover or the wheel well plastic?

Thanks, Pipe.

According to this video, you can get to it by removing the inner wheel well. You won't have to remove the bumper cover.

https://www.youtube.com/watch?v=XsPeDvJXEUs

In this video Burner's high speed was working, so he determined that he had a bad ballast resistor. In your case, if NO speed works after you jump the pins, it could be bad wiring or a connection or it could be the motor. But I'd check the wiring first.

Here's another link that shows you how to access the fans:
http://www.pedrosgarage.com/Site_3/Replace_Radiator_Fan.html

Another fairly easy test is to see if the fan spins freely.

[Starter986]

Originally Posted by piper6909

According to this video, you can get to it by removing the inner wheel well. You won't have to remove the bumper cover.

https://www.youtube.com/watch?v=XsPeDvJXEUs

In this video Burner's high speed was working, so he determined that he had a bad ballast resistor. In your case, if NO speed works after you jump the pins, it could be bad wiring or a connection or it could be the motor. But I'd check the wiring first.

Here's another link that shows you how to access the fans:
Replace Radiator Fan

Another fairly easy test is to see if the fan spins freely.

Thank you, Pipe. That Burner vid is one of the vids I watched and recall my horror at the exactly one minute mark... when he begins strong arming out the unit. The closer arrives at 17:42 when after summing up with, "So that's it. That's the whole process" he hits with, "You put everything back in the way it came out".

While I was testing the relays... jumping... running car to temp... etc. I had a constant mental loop of that video and hoping that wasn't the route I would have to take.

Snuck my hand under... fan spins freely.

Tomorrow morning I'll lift that side... peel back the liner... see if I can't access the electrical connection... to which I'll run 12V... without having to take off a bunch of parts.

Have a nice evening.

[piper6909]

Originally Posted by Starter986

Thank you, Pipe. That Burner vid is one of the vids I watched and recall my horror at the exactly one minute mark... when he begins strong arming out the unit. The closer arrives at 17:42 when after summing up with, "So that's it. That's the whole process" he hits with, "You put everything back in the way it came out".

While I was testing the relays... jumping... running car to temp... etc. I had a constant mental loop of that video and hoping that wasn't the route I would have to take.

Snuck my hand under... fan spins freely.

Tomorrow morning I'll lift that side... peel back the liner... see if I can't access the electrical connection... to which I'll run 12V... without having to take off a bunch of parts.

Have a nice evening.

Yeah, I was horrified, too!

But if you can get to the plug, after you unplug it, jump the terminals at the relay sockets and use a test light to see if you have power at the plug. The plug has 3 pins, two are power (low and high) and one is ground.

You can also try, like you said, running 12 volts to the fan-side plug and see what happens. Keep in mind the black wire is the negative and the other two are where you'd connect positive. If for some reason there's no black wire, it's the only one going directly from the fan motor to the plug.


Here's what you can do if you want to jerry-rig it. (might work if you're in a bind, but not the way I'd do it):
https://www.youtube.com/watch?v=MrD52LDH0WI

Good luck!

[78F350]

There's way too many words in this thread for me to read, but here's a link and a pic to follow up the PM.
radiator cooling fan resistor values?



I've done this in 2, maybe 3 cars now and no failures after several years.

[piper6909]

Originally Posted by 78F350

There's way too many words in this thread for me to read, but here's a link and a pic to follow up the PM.
radiator cooling fan resistor values?



I've done this in 2, maybe 3 cars now and no failures after several years.

After seeing your very impressive rear quarter replacement on This (or That? I can't remember,) I'm more than a bit surprised you'd use a jerry-rig like that. Yes it works, but.... IDK.... seems like you're inviting electrical/corrosion issues. That's just me.

To each their own.

Besides, I don't think the resistor is his problem since he has to tap on the motor for it to run.

[78F350]

Originally Posted by piper6909

... Yes it works, but.... IDK.... seems like you're inviting electrical/corrosion issues. ...

The .5 Ohm 100 watt resistors work just was well as the stock and have better cooling. I prefer them to ~20 year old used ones and pricing new Porsche ones at over $180 at Pelican makes the choice easy.

Originally Posted by piper6909

Besides, I don't think the resistor is his problem since he has to tap on the motor for it to run.

That does sound like a bad fan. I hadn't read through the discussion about the specifics, but posted here to reply with the pic of the resistors after Starter PMed me a direct question and linked me this thread.

[piper6909]

Originally Posted by 78F350

The .5 Ohm 100 watt resistors work just was well as the stock and have better cooling. I prefer them to ~20 year old used ones and pricing new Porsche ones at over $180 at Pelican makes the choice easy.

I totally agree with you on that. And I have no concerns about the resistor itself. Living in the rust belt, I get concerned about corrosion with splices. Even with the best attempts with shrink wrap and all, around here you're just inviting problems. I've seen it.

In your neck of the woods it's totally different environment and most likely not an issue.

[Seal1968]

I bought similar resistors and replaced both of my old heat-soaked and worn out factory ones. (only 1 was malfunctioning)

Total cost was under $20, and 15 minutes installation including soldering and heat shrink. Didn't have to remove the inner fender either, access is easy from underneath.

They do not look like a hack job either, they look like an upgrade. You can search, I posted up my DIY a year or so ago.

BTW...If you're buying 1 new fan, why not do both with all new resistors? Then you don't have to go through this again...and it will likely happen. The factory resistors are prone to failure as they get old, and given their location.

Enjoy!

[piper6909]

If I were in your shoes I'd go with used OE.

Check out Nationwide Auto Recycling and see if they will ship. They have a pair from a 2004 for $49 each, or Euroline Auto Recycling. They also have a pair from a 2004, and they're a little closer which may save you a bit on shipping.

https://www.car-part.com/cgi-bin/search.cgi?userSearch=int&userPID=1000&userLocation=All+States&userIMS=&userInterchange=BECAD&userSide=&userDate=2001&userDate2=2001&dbModel=62.11.1.1&userModel=Porsche%20Boxster&dbPart=674.1&userPart=Cooling%20Fan%20(Rad%20and%20Con%20mtd.)&sessionID=13000000103626776&sURL=www.car-part.com&userPreference=year&userZip=92262&userLat=33.8563000&userLong=-116.5712000&userIntSelect=1984064&userUID=0&userBroker=&userPage=1&iKey=


Click on the pic of the car on the Nationwide listing and you'll see that the car has 66K miles on it, while the Euroline has ones have 107K

[Starter986]

Originally Posted by piper6909

If I were in your shoes I'd go with used OE.

Check out Nationwide Auto Recycling and see if they will ship. They have a pair from a 2004 for $49 each, or Euroline Auto Recycling. They also have a pair from a 2004, and they're a little closer which may save you a bit on shipping.

https://www.car-part.com/cgi-bin/search.cgi?userSearch=int&userPID=1000&userLocation=All+States&userIMS=&userInterchange=BECAD&userSide=&userDate=2001&userDate2=2001&dbModel=62.11.1.1&userModel=Porsche%20Boxster&dbPart=674.1&userPart=Cooling%20Fan%20(Rad%20and%20Con%20mtd.)&sessionID=13000000103626776&sURL=www.car-part.com&userPreference=year&userZip=92262&userLat=33.8563000&userLong=-116.5712000&userIntSelect=1984064&userUID=0&userBroker=&userPage=1&iKey=


Click on the pic of the car on the Nationwide listing and you'll see that the car has 66K miles on it, while the Euroline has ones have 107K

Thank you, Pipe. I'm going to give them a call... check out the pair with shipping.

Cheers!

[Seal1968]

I wouldn't buy any electrical part used, but that's me.

You may be fine for a year or two, but it's still an electrical part that is @ 20 years old..."tail-light warranty". lol

My resistors may not be OEM, but they are certainly equivalent in quality and function.

I relocated them up and out of harm's way as well...the factory location sets them up for splashes and failure. (ergo...hot resistor + water from puddle = damage and ultimate failure)

To each his own.

[piper6909]

Originally Posted by Seal1968

I wouldn't buy any electrical part used, but that's me.

You may be fine for a year or two, but it's still an electrical part that is @ 20 years old..."tail-light warranty". lol

My resistors may not be OEM, but they are certainly equivalent in quality and function.

I relocated them up and out of harm's way as well...the factory location sets them up for splashes and failure. (ergo...hot resistor + water from puddle = damage and ultimate failure)

To each his own.

I've never had good luck long-term with aftermarket parts. Be it a water pump, fan, fuel pump, etc. They just don't last as long as the OE used parts I put in. Fans, in particular, tend to be poorly-balanced so you may even feel vibrations when they come on.

For critical parts, I either good used OE, or new OEM.

Starter's car is a 98, which means they lasted 22 years and I don't know how many miles. The ones I showed him are from a 2004 with 60K miles. That makes them 16 years old. So if his OE fans lasted 22 years, there's no reason they shouldn't give him 6 good years or more.

[Starter986]

Yeah. My 98 has ~130K. The donor car ~60K. For ~$50 per fan, used, I'll take the chance.

Pipe is correct... and I do want to mitigate balancing or noise issues. Thus, used.