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242Bleek 11-22-2007 03:54 PM

I am in the process of hooking up a 940 e-fan and relay on my 242t and I have a few questions. I have all 10 gauge wire and a 30A fusible link running from the battery positive to the relay power terminal. I ground out the low speed pin on the relay and the fan runs fine on low. But when I ground the high speed pin, it blows my 30A fuse every time. Could I just put a 40A or 50A fuse in it's place? I am using a Saab temp sensor switch to run the fan on low speed. I have another temp sensor switch and radiator hose T that came standard on my 242t, I believe it was used to control the fan that sat in front of the AC condenser. Does anyone know about this switch, and what it's temp range is? I was thinking if it came on at a hot enough temp I could use it to control the high speed on the fan. If not i'll prolly just hook it to a safety switch in the car.

tryingbe 11-24-2007 11:45 PM

I use a 30 amp maxi fuse and it never gave me problem.

vvpete 12-13-2007 12:24 PM

Quote:

Originally Posted by JohnMc (Post 1398491)
fan control, on at 210 and off at 190. The high speed is hooked up to the switch on the rad, comes on around 225 degrees.

But again, driving it hard on a hot day isn't an issue, and using the A/C on a hot day isn't either. It's just the combination of the two (sustained periods of on-boost driving on the highway with the a/c blowing) that sends the needle up.

I think the temp trip points for your fan are waay too high.

In Dallas things get hot under the hood, and my conversion has worked well in 110 deg heat with A/C on sitting in traffic. It's important to match the thermostat temp (87 deg C) with the trip point of the switch in the 3-row radiator, on at 87, off at 82 deg. Note that due to the location of the switch on the upper left, the coolant temps into the radiator are much higher at the opposite side, which means that if you have an on temp 210, that means the head is running at well over boiling, like 230 deg F or more. Even with good system pressure the temp is dangerously high.
If you use a fan switch in the lower radiator this tempdifferential is much greater, and an even lower temp trip is required. The lower hose fan switch from Volvo is a very high trip point as it was only inteneded for aux cooling when A/C was on. For primaary cooling this temp trip point should be about 80 C/175 F

The triple-row radiator I have came with a Vernet switch, on at 92 off at 82 deg C. It lasted about 1 yr with my 940 conversion . I saw some similar temp rises after a hard run in hot summer weather. I replaced it with a NAPA on 87 and off 82 degrees C and everything has been fine for the past yr and a half, except that the switches don't last more than a year, some only 8 months.

Anyone else experience the problem of failed switches?
Anyone know where to get the 22 mm thread Vernet switch that comes in the Nissen radiators?

FYI some part numbers and equivalents for the temp switch, 22mm thread for the aftermarket 3 row radiator:

Vernet p/n ??? on 92 off 82
NAPA p/n FS150 on 87, off 82 C (198/188F)
FAE p/n 201-0809 on 87, off 82
Wahler VWW022209 on 87, off 82
-
I'm using the stock Bosch relay dirrectly from the battery, I don't use a fuse, and wonder why anybody would think they need one, as this power control relay is designed to be a fuse in itself, which is the way it was used in the 940.

davashcow 12-15-2007 10:28 PM

Quote:

Originally Posted by vvpete (Post 1537777)
I think the temp trip points for your fan are waay too high.

I'm using the stock Bosch relay dirrectly from the battery, I don't use a fuse, and wonder why anybody would think they need one, as this power control relay is designed to be a fuse in itself, which is the way it was used in the 940.

I was looking at a used 245 off Craigslist last week at the owner's home and commented that the owner's other car (a 940) had the fan running which was weird since it was cold out. He said he hadn't driven it for hours. We lifted the hood and found the fan happily running and the fan relay merrily smoking and giving off lots of heat. I suggested that he disconnect the battery, so he did and end of story but that could've been a fire. I will use a fuse when I hook up my 940 fan to my 302 conversion.

brucepick 01-01-2008 11:25 PM

I've been using Wahler switches since I installed the fan in summer of '05. No failures through this past fall. After that the weather cooled off and the temp switche(s) don't activate again till spring.

500dollar744ti 01-21-2008 04:20 PM

if you choose to use a 90-94 chrysler lebaron 3.0 v6 efan, for the record it is about 2.25 inches thick, this is the style you want because of thickness. they should also be found on same year spirit/acclaim with 3.0 v6.

trim along red lines to fit volvo 740 radiator.
http://xs223.xs.to/xs223/08041/lebaronfan277.jpg
^^^ only picture i could find of fan for mockup lines is this aftermarket replacement, the actual mopar oem fan is even thinner. the one i have is oem mopar.

Volvit 01-22-2008 11:31 AM

my $.02 for those who need it...

I did the 940 efan swap yesterday on my 86 245. And yes it is as easy as everyone claims it is.

First I trimmed the shroud right next to the flaps as seen in the picture ("borrowed" from volvo940tuner)

http://www.evolvolution.com/images/940efan.jpg

I attached it to the radiator with two self-tapping screws up top and two zip ties at the bottom.
That was the easy part. Next is the ever dredded (sp?) wiring. Which when explained in plain english is cake.

I suggest when you pull the fan from a yard you leave as much stock wiring as possible. I left the wires going from the fan into the relay as they were on the 940. I cut the wires COMING OUT of the relay and the black ground. There should be a total of 4 wires you have to worry about (or 3 if you don't need a high and low speed). 1 is a black ground which is up to you where you ground it, I used the fuse holder by the battery. The red wire is second. It should be fused, it looks like most use up to and above 30 amps. I took another route, it was a small circuit breaker (for lack of better words), this way if it trips it can reset itself, not cause a fire, and I don't have to worry on a hot day about over heating. I hooked the red wire directly up to my battery. At this point you can ground the blue/black wire and low speed should work or ground the white/black for high speed. I chose low speed, because it was enough air flow, for my weather. So I took the blue/black wire and ran it across the firewall behind the motor and connected it into the Saab T-Housing with a coolant sensor fan switch from an 85-92 VW Jetta/Golf 1.8 SOHC. It was the same thread size and everything, cost about $10 from a VW garage. After connecting the Blue/Black wire to one terminal, I grounded the other terminal to the washer fluid bracket. The switch is constantly open and when the temperature is reached it closes and completes the circuit and grounds the fan, turning it on. There was something goofy about the saab switch which I didn't understand, it seemed that it was always closed. Either way it works as it's supposed to now. I don't think I forgot anything, let me know if I did. The whole deal cost was $15 for fan and relay/wiring, $3 for the Saab 900S T-Housing, and $10 for the sensor. Total = $28 + spare wire, connections, screws, zip ties, etc. So call it $30.

Crazychopstick 02-08-2008 02:17 AM

I wouldn't trust zipties to mount the lower part of the fan.

http://i12.photobucket.com/albums/a2...o/DSC00332.jpg

A couple bucks at the Home Depot.

Volvit 02-08-2008 12:46 PM

Quote:

Originally Posted by Crazychopstick (Post 1620736)
I wouldn't trust zipties to mount the lower part of the fan.

Why's that? To much vibration?

davashcow 02-11-2008 12:39 PM

Lowe's sells mil-spec zipties that are rated to 175 pounds. I've seen some people on this board that would consider using these as motor mounts:wtf: Not to name names, but he lives a couple hundred miles from me:neener:

Crazychopstick 02-11-2008 11:14 PM

Quote:

Originally Posted by Volvit (Post 1621143)
Why's that? To much vibration?

I dunno.

Call me crazy, but I'd take a few sheet metal screws over zipties anyday, the plastic can deteriorate eventually, and I never found a good place to slip them besides mounting them to the radiator.

A few peices of metal, a drill and 10mins is all it takes to secure your e-fan to the radiator support. That's almost as fast as changing ziptie motormounts!

mullen1120 05-18-2008 02:03 PM

for the temp sensor, whats the best way to mount that in the rad hose?

Midgie245R 05-19-2008 10:29 PM

Quote:

Originally Posted by mullen1120 (Post 1790945)
for the temp sensor, whats the best way to mount that in the rad hose?

If you are talking about using a saab sensor, it screws into a t-piece that is inserted into the hose. eg:

http://i134.photobucket.com/albums/q...volvo/efan.jpg

totaled108 05-20-2008 12:58 AM

I had been using the stock sensor IN the radiator with great results. I saw that a few people have used this rad hole method. So I gave it a shot, and it failed for me. The sensor in the rad has two settings. 95c, on, 85c off. The other one too high. Anyways, once it turned on the fan, the gauge was reading high. Then it wouldn't turn off, even when the gauge went below 9 o'clock. Hooked it back up to the 'A/C' switch in the rad, it switch on and off in traffic at the perfect times. That sesor is rated at 92c on and 82c off. Both times I tested them it was ~91F outside.

I think I am going to put the Saab T in the bottom rad hose as a coolant drain, so I don't have to remove the hose and make a mess. :)

mullen1120 05-20-2008 05:49 PM

the only temp sensor ive notice in my rad is on the top left, has two wires, but i thought from reading the other post that this is hooked up to the front ac fan and only turns on for extreme heat? is that what your talking about?

my fan is from a 940 i have the relay and everything and i modded my original shroud to fit the 940 fan looks real good and stock.

any ideas on what the best way to go about the temp sensor is? b/c im about to just wire it up to a switch on my dash lol

totaled108 05-20-2008 08:53 PM

Quote:

Originally Posted by mullen1120 (Post 1795362)
the only temp sensor ive notice in my rad is on the top left, has two wires, but i thought from reading the other post that this is hooked up to the front ac fan and only turns on for extreme heat? is that what your talking about?

my fan is from a 940 i have the relay and everything and i modded my original shroud to fit the 940 fan looks real good and stock.

any ideas on what the best way to go about the temp sensor is? b/c im about to just wire it up to a switch on my dash lol



Quote:

Originally Posted by totaled108 (Post 1794219)
Hooked it back up to the 'A/C' switch in the rad, it switch on and off in traffic at the perfect times. That sensor is rated at 92c on and 82c off. Both times I tested them it was ~91F outside.

I think I am going to put the Saab T in the bottom rad hose as a coolant drain, so I don't have to remove the hose and make a mess. :)


Yes, its for the A/C fan, that doesn't exist in my car. I think some of the switches in the rad, for the A/C, are rated high. I got lucky enough to have a lower rated switch. Get one that are in the range of the one I have, and you'll have no problem.

Works great for me

http://i24.photobucket.com/albums/c2...8/P3210176.jpg

mo5005 05-21-2008 03:54 AM

Is it safe to wiring the relay straight to the positive terminal? Is anyone worried about draining the battery out besides me????

Lets just say its a 110* degree day, the fan could hypothetical run forever if you are using a 87/92 degree switch.....right???

totaled108 05-21-2008 07:42 PM

Quote:

Originally Posted by mo5005 (Post 1796321)
Is it safe to wiring the relay straight to the positive terminal? Is anyone worried about draining the battery out besides me????

Lets just say its a 110* degree day, the fan could hypothetical run forever if you are using a 87/92 degree switch.....right???

Thats in Celcius, not Fahrenheit. The switchs are rated in Celcius. Our bodies are 98.6F, or 37C. So 92C is 197.6F, and 82C is 179.6F. So when I say the switch turns on at 92C, the coolant is a hot 197.6 degrees Fahrenheit. Most automotive thermostats are 87-95 degrees Celcius. I think mine is 92C.

I wired mine through a relay straight to the battery. Also, there is a switch and LED, so I can control it manually if needed, and I know when it turns on by itself.

mullen1120 05-22-2008 11:33 AM

sweet, ill wire it up and see when it turns on, thanks guys

mullen1120 05-22-2008 09:54 PM

Quote:

Originally Posted by MikeSr. (Post 1312917)
I did an electric fan swap from a 940 into my 1990 740 GLE 16V, using the big radiator, and the stock Volvo relay. This is a very easy swap. The relay has two wires coming out of the middle which are grounds used by the 940 ecu to turn the fan on, one at high speed and one at low speed. I hooked these wires to temp sensors, one in the radiator and one in the lower radiator hose, like a 240 turbo. The low speed wire is on the lower radiator hose. On each sensor, i took the other connector and sent it to ground. Main power wired to the battery+, Done! Now the fan turns on if either sensor reaches it's temp setting and completes the ground circuit.
Much quieter car now- and it runs cooler with the big radiator. Anybody with an engine driven fan should do this swap.

Also put a late 940 intercooler in at the same time. Wonder why?

what is better about the 940 intercooler?

mullen1120 05-23-2008 09:48 AM

okay all wired up, used the rad temp sensor and grounded it.
now the dash temp gauge never went past half but i used a laser temp reader gun (i use it for HVAC) to double check and the rad hoses never went past 210, but the red block was reading 225 when the fan came on.
what do you guys think, should i get another temp sensor?

tjts1 05-23-2008 05:48 PM

Quote:

Originally Posted by Midgie245R (Post 1793826)
If you are talking about using a saab sensor, it screws into a t-piece that is inserted into the hose. eg:

http://i134.photobucket.com/albums/q...volvo/efan.jpg

What temps the temp rating of your thermoswitch?

marshcat 05-28-2008 06:42 PM

Why is an E-fan so good? Does it really matter if it's powered by the engine or by the battery?

totaled108 05-28-2008 07:56 PM

Quote:

Originally Posted by marshcat (Post 1810071)
Why is an E-fan so good? Does it really matter if it's powered by the engine or by the battery?

Honestly, after having if for a while, the only thing I am seeing it do is, quiet down the engine in stop and go traffic. I haven't seen a noticeable increase in fuel economy (1-2 mpg at the most) or power, though the throttle does feel alittle snappier. Also the engine bay is alittle more open and getting at the front of the engine is easier.

People have said that, the water pump bearings will last longer with out the mass spinning on it. I know a few of my blades had alittle plastic chewed of on the ends, so it may be be putting alittle stress on the bearings, because its not perfectly balanced. But I think that might be taking it a bit far.

If I ever need to go back do to a failed E-fan, I'll do it and stay stock, but for now itd nice to have the quieter engine bay.

that my $.02

:-P

MikeSr. 05-28-2008 09:17 PM

Quote:

Originally Posted by mullen1120 (Post 1799693)
what is better about the 940 intercooler?

Oh, I put it in for +t conversion. Now I am gonna put an ebay cooler in. I have no turbo on this car, so as it comes together, I wanted an intercooler in place an the radiator change was a good time to do it.
Still no turbo, but coming soon.


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