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MG Midget and Sprite Technical - ELECTRIC COOLING FAN 76 1500
|My 76 midget 1500 came with an electric cooling fan, but no thermostat to turn it on and off. Should I install an electric thermostat to turn the fan on and off? If so, any recommendations on brand, etc? Also, should I install my old mechanical fan to assist the cooling or leave it off? My electric fan is fitting on the front so it will not interfere. I live in Miami, Florida so it is not necessary to supply hot coolant to the heater. However, overheating is a problem. Thanks ....AL|
|Al. If there is no fan switch I assume your fan runs all the time. I bought a Kenlowe fan for my '65 Sprite which came with a capillary tube which goes in the top hose and this is effectively the thermo switch for the fan. Their sales blurb says that the fan allows the engine to run at a hotter and therefore more efficient temperature. I'm not sure if I'm convinced because I think my engine has been getting too hot this summer and I'm in the UK where we don't get temperatures as high as you do in Florida. I'm thinking about putting my mechanical fan back on to assist. It does say in the instructions that if you have had overheating problems you can put your blades back on again.|
You could fit a manual switch but you would be for ever watching your temp gauge. I dont know of anyone who does a separate thermo switch, but I'm sure someone on here will.
Most LAPS carry Haydn switches. Generally a fixed temperature or an adjustable. Guess which one costs more? I used the adjustable on my 72. I set it so that it kicks in at a temp a little higher than the thermostat does, so that there is no fan action until it is actually needed. They will work fine with any fan. It is a good idea to have a manual over-ride switch to allow you to force the fan on at will.
The electric fan will be more efficient behind the radiator than in front, but not necessarily more cooling than the electric combined with the mechanical.
The heater matrix does give you a bit more water in the system as well as the option to fire up the heater fan and give yourself a bit more cooling when the guage is trying to read in the oil pressure range ;-)
David "keeping my cool" Lieb
|I did mine like David. I rigged a toggle switch under the dash to allow me to manually turn it on or disable it completely. It is on a switched circuit too so it won't stay on after you shut the car down. I also rigged up a little light that comes on so I know if the fan is running or not. I have the adjustable type and have it set so it only comes on when things are getting a bit warm. It seems to be working great as it comes on only when hot and idling, a minute or so of forward motion and it turns off again. I think that's just perfect; no motor fan sapping energy all the time (but especially when revving high when you need the fan the least (because you're moving down the road) and only an electric drain when you get caught idling too long and that's pretty rare (non existent the last few drives as it's cold here now). I got caught in a traffic jam on a really hot day and despite not moving, the electric kept up keeping it cool, although things were starting to get a bit dicey.|
|J Van Dyke|
|Thanks for all your comments. Has anyone used the adjustable thermostat offered from Victoria British for their Electric cooling fan (2-7769) ? Thanks ....AL|
|Firstly if the car overheats when moving forward at say more than 20MPH then no amount of fans will keep it cool, there will be another fault. The fan is merely there to stop the engine overheating when stuck in traffic or crawling along in the centre of town.|
Therefore the advantage of an electrical fan over the mechanical fan is that it does not take energy when the car is moving and the fan is of no use, whereas the mechanical version is sapping energy as the engine drives the car forward, in fact the faster you travel the more power is wasted.
I have my electric fan (From a metro) switched by a radiator switch fitted into many thousands of radiators and can be bought from many motor parts outlets. Not easy as a boss is required to fit it to the radiator. Also I have a manual over ride switch, most important in my opinion and I tend to switch it on everytime I am stuck in traffic, the auto switch is simply there in case I forget.
So you need to either fit a rad switch or find an after market thermostatic switch that can be installed in the top hose.
|Robert (Bob) Midget Turbo|
I have an electric fan in front of the radiator as an extra safety measure to the factory mechanical fan. It is not now on a thermostat, but will add that eventually. So far I haven't needed the electric fan after having the radiator boiled out.
There has been talk on this list and others that it is better to leave the mechanical fan installed, as it helps prevent vapor lock and associated fuel problems while moving slowly in traffic. Helps lower underhood temps. Makes sense to me.
If your viscous fan clutch is really working correctly (big if,) you shouldn't notice any loss of power or other negative affects.
This thread was discussed between 19/10/2009 and 21/10/2009
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