Electric fan bypass switch
- Thread starter 84cutspreme
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With a small block I wouldn't worry to much about it. Put in a 180 degree thermostat (carbed) or 160 degree (Fuel Injected) and just let it cool off naturally. Carmakers put in High temp thermostats so you could be warm driving on snowy roads and to eak out the last little bit of emissions and fuel economy.
With a 355 and a 650 holley and 3.73 gears, none of these 3 apply to you. Don't complicate things that don't need to be complicated. It's just one more thing you will disable when it goes bad.
My old 95 VW Golf GTI had electric fans that ran after shutdown. The engine had a supplemental electric coolant pump which cooled the entire system.
In your case the electric fans, whether controlled by a sensor or timer, will only cool the rad by blowing hot air over the engine. What does the coolant temp gauge show once the engine is shut down(with the ign switch on?) Just wondering?
I'm sure the VW engineers specced a higher capacity battery to account for the fans run time after shutoff.
In your case the electric fans, whether controlled by a sensor or timer, will only cool the rad by blowing hot air over the engine. What does the coolant temp gauge show once the engine is shut down(with the ign switch on?) Just wondering?
I'm sure the VW engineers specced a higher capacity battery to account for the fans run time after shutoff.
I am beginning to agree with previous comment about overcomplicating things. I have only noticed a few times where I was restarting car pretty soon after shutting down. like getting gas while motor was at 190-195 when shutting down and fans were just coming on. when I went to restart as soon as it started fans came on and temp was at 210-215
German cars also generally use deep cycle batteries that can run an electric motor for longer on the battery without causing permanent battery damage.
US cars use starter batteries and we cannot drain them as low as a deep cycle battery without causing permanent damage to the capacity of the battery.
German batteries actually have lower starting capacity than a similar size US battery (like 220 CCA vs. 420 CCA for the same size battery) because of the battery type difference.
210-215 isn't overheating so I would not wire the fan stay to on after you shut the engine down. You can always wire in a bypass so you can turn the fan on when the engine is off.
Temp switchs generally work by going to ground when they reach temp. The wire to the temp switch should trace back to the 85/86 pole of a relay somewhere. It you splice into the wire going to a tenp switch and ground it, what ever tbe temp switch turns on should turn on.
I must be lost on this whole post, because to me it's brain numbing the thought going into it! Sorry!! Timer, controller, on, off, power, no power.
If you put a simple temperature controller with continues 12V power, set them to 190 degrees to come on they will cool the rad down to 190 then shut off and they will heat soak from the block an start again once they heat soak the block an radiator temp gets over 190 degrees, this is the reason mine come back on after shutdown.
It's sounds like what you want is a temperature controller running on continues power but the ground wire running threw a temperature sensor on the block? That's going to eat a battery. Because once your car is shut off there is no flow, only heat soaking so having fans trying to cool the block it is a difficult.
To add in a timer to me, that's a hard sell an truly unnecessary.
Maybe wire the one closes to inlet for rad to continues power and the other fan to accessories. The one closes to inlet is getting the heat soak from block an the other ones off not using power.
I am not trying to argue, l'm trying to understand!!!!
If you put a simple temperature controller with continues 12V power, set them to 190 degrees to come on they will cool the rad down to 190 then shut off and they will heat soak from the block an start again once they heat soak the block an radiator temp gets over 190 degrees, this is the reason mine come back on after shutdown.
It's sounds like what you want is a temperature controller running on continues power but the ground wire running threw a temperature sensor on the block? That's going to eat a battery. Because once your car is shut off there is no flow, only heat soaking so having fans trying to cool the block it is a difficult.
To add in a timer to me, that's a hard sell an truly unnecessary.
Maybe wire the one closes to inlet for rad to continues power and the other fan to accessories. The one closes to inlet is getting the heat soak from block an the other ones off not using power.
I am not trying to argue, l'm trying to understand!!!!
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