Cascade Crew

nonsensekid20 · Posted: Mon Oct 29, 2012 3:09 pm Post subject: Coolant Fan temperature switch

Alright, looking around the interweb, I can't seem to find a temp switch that will work on my car. I see plenty, but none show what temps they work at. I want the fan to come on at 195 and off at 180. I found a BWD TFS5 that looks like it would work, but have no idea what temp it is. Ideally I want one with a male-end connector, not that round knock sensor looking thing. Help! please and thank you

RSFreak · Posted: Mon Oct 29, 2012 5:06 pm Post subject:

Had a universal one in my '91 RS that had a rheostat to control the on temp. Not sure how it determined when to turn off, but it worked really well. It was already on the car when I bought it so I have no idea of the brand or where to find it.

iansane · Posted: Mon Oct 29, 2012 6:27 pm Post subject:

Hayden makes those universal ones with the rheostat. They're at pretty much any parts store. However, I remember Paul posting a good list of them...

Ah, here's the link;

http://www.wellsve.com/custom_searches/ds_fans.php?showall=yes

aaron_sK

nonsensekid20 · Posted: Tue Oct 30, 2012 12:06 pm Post subject:

Are there any I don't have to order through Summit and just pick up at Oreillys?

aaron_sK · Posted: Tue Oct 30, 2012 12:54 pm Post subject:

If only Ian had posted a list of sending units that you can pick up at ORiellys... Surprised

QwkTrip · Posted: Tue Oct 30, 2012 4:06 pm Post subject:

Does somebody have a resume ready?

chevymad · Posted: Tue Oct 30, 2012 5:48 pm Post subject:

Not sure about Oreillys catalogs, but the napa ones for fan switches really suck bad. I've spent several hours a couple different times trying to find one. You almost have to go through the picture book, page by page, then when you find one you have to go to the computer and check. Sometimes the specs from one to the other dont match.

Then the last one I bought didnt turn on/off like it was supposed to. So I look up the specs again and find that there's an allowable 20* swing in turn on temp. It was spec'd at 215* on.. but the "range" was from 215 to 235. Where do you think my switch turned on at? Thats right 235. Sad

Twilightoptics · Posted: Tue Oct 30, 2012 6:05 pm Post subject:

You just can't beat getting the one you want from Summit. Some of those local sensors are upwards of $40. Get it from Summit and be ahead.

The cheap adjustable ones that oriellys and autozone sell are crap. I went through 3 and they didn't work right. I finally just grounded the relay to one fan in my Mazda and said the hell with it. ECM control is the way to go anyway.

iansane · Posted: Tue Oct 30, 2012 8:24 pm Post subject:

BluFbdy · Posted: Tue Oct 30, 2012 11:06 pm Post subject:

Half the time he can throw a rock and hit Luke lol

Why do you need a male end connector? I used a female spade connector when my knock sensor style one crumbled, it slides right on lol

Dammit nick always complicating things.....just like the diode, simple answer just do it Lol

DBL_TKE · Posted: Wed Oct 31, 2012 9:10 am Post subject:

I run a Hypertech fan switch that turns on at 200*F and off at 185*F. Got it for $45 through Baxter's.

nonsensekid20 · Posted: Wed Oct 31, 2012 11:13 am Post subject:

Damnit Andy with you and your diodes. Mad

I want the fan switch itself to have a male end but it doesn't really matter. I found this one on the link Ian sent. What I couldn't tell from that site is if it will fit into the block because I don't know the thread pitch. http://www.oreillyauto.com/site/c/detail/MPI0/28481.oap?ck=Search_sw1802_-1_2538&keyword=sw1802
This is that same switch at O'reillys but it says its for a BMW. -.-

I want one that turns on around 195 and off at 180. Give or take a bit.

Thought this was the right one, but says it's for a Ferd. http://www.oreillyauto.com/site/c/detail/BWD0/TFS12P.oap?ck=Search_sw510_-1_2538&keyword=sw510

aaron_sK · Posted: Wed Oct 31, 2012 11:21 am Post subject:

First one is metric straight thread with a washer. No fitty no way.

The second one is 3/8" NPT which IIRC is what the SBC heads are tapped as.

You do understand the difference between buying something based on application and buying something based on specs, don't you?

nonsensekid20 · Posted: Wed Oct 31, 2012 11:45 am Post subject:

Well considering I just said I didn't know the thread pitch, application is what I was going for. But as long as the 3/8x18 will fit then I'll be looking for that one.

aaron_sK · Posted: Wed Oct 31, 2012 12:42 pm Post subject:

Could also be 1/2" NPT. Those were the only two sizes that I have ever seen on an SBC.

The 3/8-18 is real common on American cars. They used a lot more taper in general.

Remember that pipe thread is rated in ID, so a male sensor listed as 3/8" will be much larger when you measure it.

nonsensekid20 · Posted: Wed Oct 31, 2012 1:19 pm Post subject:

Just to be sure I'll have to check one of the water port threads. Oh and while we're on the subject, where's a good spot to put this sensor? Usually you'd put it on the driver side head, but that's where I have the sensor for my temp gauge inside. I had one of these sensors in the water jacket port directly under the upper water hose but the fan never kicked on so I was thinking the water up there wasn't the true temperature for some reason. Nor is there so much room for a sensor underneath that hose. There's one in the back of the intake manifold too but IIRC the sensor didn't fit there either. (FYI this kit was a cheap kit from JEGS so most likely the sensor was just shitty).

aaron_sK · Posted: Wed Oct 31, 2012 1:26 pm Post subject:

Both heads have the same port.

Head will run a bit hotter than the intake usually, but once the t-stat opens the fan should have come on assuming the sensor was the correct temp and working properly.

Another thing to note is that the larger push-on connector used with the factory sender and some kits (Jet for instance) is known to fail.