Electric fans?

[Cecil14]

I think I would agree. I don't really care what temp the coolant is after it's been cooled. What temp it is coming out of the engine is far more important.


aa

[racerx12003r1]

This has turned out to be one heck of a thread. Lots of good info about electric fans. I know my last fan was wired to the switch with a toggle switch to control the relay. Ofcourse it was on a car I ran at the drag strip. Thanks guys.

[serehill]

It is a great thread my thought on controller was to have a single thermal unit to control one fan & feed the second relay straight off the A/C for two reasons. One to cool the engine & 2 to ensure air constantly flows across the condenser which would improve the efficiency of the A/C. A/C units on mechanical fans at idle without movement is non existent. This would be far better the mechanical fan. I've also thought some dash pilot lights would be good. one of the down sides of the electric system is you don't know when it quits. Interesting discussion about the temp probes. Location seems to be aft the radiator. The contour fan set up looks far more like what I would want than the Taurus one I bought. Guess it's back to the drawing board but I like that approach. Thanks for the input.

[SJTD]

Nice find on the BMW probe. I've got a Taurus fan in my CJ with just the low speed hooked up with an adjustable air temp sensor behind the radiator. Been looking for wet sensors with those set points.

Wanted a the same numbers for the Wag set up like serehill suggests but would was going to wire it so the hi speed would be the high temp or the AC.

What are the off points for the BMW probe?

[Cecil14]

If you hit rockauto they have specs on the different probes (both on and off temps).


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[serehill]

you have a link Cecil?

[Fleg]

My BMW probe came in yesterday. Tried to mock it up today. I thought it was a M10x1.5, it's not. It is actually a M14x1.5. That's a little bit of a problem. I've found that they do make a 3/8 to m14x1.5 adapter but it may as well be unobtainium.

[Cecil14]

Was out of town last night, didn't have a chance to pull up the info until this morning. Here's the specs from RockAuto's site:

VALEO Part # 820220 {#61311378073, B2623} Closing Temperature [°C]: 85; Shut-off Point [°C]: 93; Opening Temperature [°C]: 90; Switch Point [°C]: 98; Thread Size: 14x1.5

They don't have a great description of 61318361787 like the higher temp one, only the closing and opening temps of 80°C/88°C, respectively. It does share the same 14x1.5 thread.

I don't see a way to link directly to RockAuto's search results, everything is done via backend script and the main address stays the same. Just hit their site and punch in the part number above though and you'll get several options of manufacturers.

Autozone lists the probes as well, but they want something around $30/each instead of $11.


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[Cecil14]

Here is a 3/8" to M14x1.5 adapter...I don't know how viable it is to order just one from this company:

http://catalog.serto.com/onlinekatalog/ ... 1000023979

Another thing you might be able to do - instead of using the radiator hose adapter you bought could you not use a piece of exhaust pipe and have an M14x1.5 bung welded on? I imagine you could get the tiny chunk of stainless exhaust you'd need pretty cheap. Can't imagine it would be that much to weld the bung on either.


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[Fleg]

I did look at the local autozone today for a piece of pipe and couldn't find a 1.5" od section to work. Did a quick mockup of the wiring harness and will finish it tomorrow. Took a picture of the fan mounted in the engine bay. Lots of room

[Cecil14]

For the pipe I would just hit up your local exhaust shop. They might even have a piece of scrap they'll give you cheap.

Otherwise everything looks great. Plenty of room without the crank fan in there.


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[Fleg]

Drove the Jeep around today. The first fan did kick on and cycled a few times. Some loose ends I need to tie up and some things I would change but it works really well so far.

[Fleg]

One of the issues that I've had is the Volvo relay is a latching style relay. Only one relay can be active at a time due to it build designed for a dual speed, single fan. In using a relay built like that for a single speed, dual fan setup only one fan would operate at a time. Finally got a chance to work through that issue and came up with a pretty simple solution. Now the relay operates as a true dual relay and I have dual fans that operate based on temperature.

[racerx12003r1]

I just got back from the local Pull A Part here in Charlotte with a Contour fan assembly to try and put on my old truck. I got the harness and all. When I wired it up to a battery, I found it has 2 speeds. I figured it would have run one fan, then the other. Are y'all running yours as seperate fans or both fans with low and high?

[Fleg]

The contour fan is a dual fan single speed as far as I know.

[racerx12003r1]

I noticed there is a small wound resister at the bottom of the fan shroud. There is a picture of it earlier on this post. When I got mine, I got harness and all. It will run both fans at 2 speeds. When I looked at it, it looked like a resister for a heater blower fan. Its down in the bottom corner of the shroud housing. Ill get a picture of it when I get home from work this afternoon.

[Fleg]

I have that same coil. Apparently that is some kind of variable resistor but I didn't use it. I have my fans set for one to come on then if the temp increases the second one comes on using a modified volvo relay.

[Fleg]

If you did want to use both fans in a high/low setup you could use a unmodified volvo relay pack. Wire the two fans in series for low and parallel for high.

[racerx12003r1]

Oh ok. I'm still up in the air about the way I'm going to run it. In your opinion, do you think there would be any benefit to high and low speed fans verses running 1 fan then 2?

[Fleg]

Oh ok. I'm still up in the air about the way I'm going to run it. In your opinion, do you think there would be any benefit to high and low speed fans verses running 1 fan then 2?

I don't think using the variable resistor is of any benifit. That's just wasting amps. You could do the series/parallel wiring but might be a little complicated for the average person. I'd still lean towards using the fand independently with a modified volvo controller.