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- Joined
- Aug 6, 2007
- Messages
- 3,874
- Reaction score
- 1,734
- Points
- 113
- Location
- Macon/Fort Valley, GA
- Vehicle Year
- 1999
- Make / Model
- Ford
- Engine Type
- V8
- Transmission
- Automatic
- 2WD / 4WD
- 4WD
thermal switch temps for e-fan conversion?
So I'm soon to do an E-fan conversion on my 99 4.0L but I figure this will apply yo most Rangers (and other vehicles) doing a similar conversion.
Ok so my truck is a stock 99 Ranger 4.0L 4x4. Several years ago I converted it to a dual core Explorer Radiator because the stocker split and I had it on hand. Well the trimmed 4.0L fan shroud doesn't quite align right with the engine driven fan and is wearing away at the fan blades. Might not be an issue, but I don't like it so it's getting fixed. To fix I can either replace radiator, fan, and shroud with unmodified stock components, or I can finally do an E-fan swap like I planned to years ago.
Radiator and fan change: ~$200 and loose cooling capacity
E-fan: ~$60 plus less drag and potentially better mileage
Obviously I'm leaning towards the E-fan, and I've had a Taurus E-fan (and Volvo relay IIRC) sitting on the shelf for several years.
To control this fan I'll need a two speed fan switch and several years ago I came up with a list of potential switches, but then never carried on with the project. Finally got back around to it and need to decide on which temps would be best suited to the Ranger.
List of Switches:
VW high range switch (temps too high)
95-81/102-91 (°c)
203-178/215-196 (°f)
BMW high range
91-86/99-94 (°c)
196-187/210-201 (°f)
m14x1.5
P/N: 61 31 1 378 073
VW mid range switch
85-74/93-82 (°c)
185-165/199-180 (°f)
m22x1.5
P/N: 251959481k (Wahler)
BMW low range switch
80-75/88-83 (°c)
175-167/190-181 (°f) (180 on for low according to tech library)
m14x1.5
P/N: 61 31 8 361 787
VW low range switch (Temps too low)
75-70/82-77 (°c)
167-158/180-170 (°f)
With the Ranger having about a 195 degree thermostat, I'm thinking that the VW and BMW high range switches are too high. Don't want engine temp coolant being pumped right back into the engine. My thoughts are that if the coolant leaving the radiator is that hot the heads are already gone. Similar for the VW low temp range, it's too low to be effective.
With a stock single core radiator I think the mid range VW would be a good option since it would kick on when the coolant exiting the engine is 10 degrees cooler than leaving the engine. IMO the 199 degree on temp might still be too warm for coolant going back into the engine. That's hotter than the thermostat, I'm pretty sure I want high speed to be kicking in well before the radiator gets to that point. With the M22x1.5 thread size this one is also a little difficult to get a hose adapter for, but I could make it work even if I have to buy a tap.
Mid range BMW sensor might be a little low on the low side. The dual core V8 radiator might keep coolant temps low enough while moving that it never switches on which is exactly what I want. Problem comes if it sits long enough for the fan to switch on. With a 167 degree off temp, will it ever turn back off? IMO high speed kicking on at 190 for radiator exit temps would be great. Means it should kick on well before heads ever become at risk and hopefully off temp is still low enough to turn off.
I know that the idea is to have the fan trying to control radiator temps and the thermostat controlling engine temps, hence the reason for placing the switch in the lower rad hose.
FWIW I also intend to wire it with manual on switch and for high speed fan to come on with AC.
So which switch would be good for keeping the radiator cool without running the fan constantly?
So I'm soon to do an E-fan conversion on my 99 4.0L but I figure this will apply yo most Rangers (and other vehicles) doing a similar conversion.
Ok so my truck is a stock 99 Ranger 4.0L 4x4. Several years ago I converted it to a dual core Explorer Radiator because the stocker split and I had it on hand. Well the trimmed 4.0L fan shroud doesn't quite align right with the engine driven fan and is wearing away at the fan blades. Might not be an issue, but I don't like it so it's getting fixed. To fix I can either replace radiator, fan, and shroud with unmodified stock components, or I can finally do an E-fan swap like I planned to years ago.
Radiator and fan change: ~$200 and loose cooling capacity
E-fan: ~$60 plus less drag and potentially better mileage
Obviously I'm leaning towards the E-fan, and I've had a Taurus E-fan (and Volvo relay IIRC) sitting on the shelf for several years.
To control this fan I'll need a two speed fan switch and several years ago I came up with a list of potential switches, but then never carried on with the project. Finally got back around to it and need to decide on which temps would be best suited to the Ranger.
List of Switches:
VW high range switch (temps too high)
95-81/102-91 (°c)
203-178/215-196 (°f)
BMW high range
91-86/99-94 (°c)
196-187/210-201 (°f)
m14x1.5
P/N: 61 31 1 378 073
VW mid range switch
85-74/93-82 (°c)
185-165/199-180 (°f)
m22x1.5
P/N: 251959481k (Wahler)
BMW low range switch
80-75/88-83 (°c)
175-167/190-181 (°f) (180 on for low according to tech library)
m14x1.5
P/N: 61 31 8 361 787
VW low range switch (Temps too low)
75-70/82-77 (°c)
167-158/180-170 (°f)
With the Ranger having about a 195 degree thermostat, I'm thinking that the VW and BMW high range switches are too high. Don't want engine temp coolant being pumped right back into the engine. My thoughts are that if the coolant leaving the radiator is that hot the heads are already gone. Similar for the VW low temp range, it's too low to be effective.
With a stock single core radiator I think the mid range VW would be a good option since it would kick on when the coolant exiting the engine is 10 degrees cooler than leaving the engine. IMO the 199 degree on temp might still be too warm for coolant going back into the engine. That's hotter than the thermostat, I'm pretty sure I want high speed to be kicking in well before the radiator gets to that point. With the M22x1.5 thread size this one is also a little difficult to get a hose adapter for, but I could make it work even if I have to buy a tap.
Mid range BMW sensor might be a little low on the low side. The dual core V8 radiator might keep coolant temps low enough while moving that it never switches on which is exactly what I want. Problem comes if it sits long enough for the fan to switch on. With a 167 degree off temp, will it ever turn back off? IMO high speed kicking on at 190 for radiator exit temps would be great. Means it should kick on well before heads ever become at risk and hopefully off temp is still low enough to turn off.
I know that the idea is to have the fan trying to control radiator temps and the thermostat controlling engine temps, hence the reason for placing the switch in the lower rad hose.
FWIW I also intend to wire it with manual on switch and for high speed fan to come on with AC.
So which switch would be good for keeping the radiator cool without running the fan constantly?
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