Keep your classic Ford’s engine cool by fitting up an electric fan conversion — you might just gain a few extra horsepower in the process…
If someone offered you a few extra bhp for nothing, you wouldn’t turn it down, would you? After all, people go to great lengths, spending thousands of pounds squeezing every last pony out of their engine, so if there is something up for grabs that will actually cost you nothing at all then it has to be worth it, right?
The typical classic Ford engine — whether it’s a 1300 Crossflow, Essex V6 or a 2-litre Pinto — will have left the factory with a manually driven cooling fan that can be found bolted to the water pump pulley. The idea is that they will draw additional air through the radiator to aid cooling, but in doing so they have to use a certain amount of the engine’s power to force the fan blades through the air.
Having a fan that is constantly moving will also mean that the engine will take longer to get up to the correct working temperature, which means you’ll be running the car on choke for longer periods and using more petrol in the process. So by removing the aforementioned mechanical fan you will gain more power. Figures of around 8 per cent are typical, you may even save a few pennies on the weekly fuel bill, and your engine will be happier as it will reach its optimum temperature far earlier, especially on short journeys.
So you see, simply by throwing away that old mechanically driven fan you can gain around 5-8 bhp for every 100 bhp that your engine produces, and it’s all free!
OK, so maybe it’s not technically free as you will now have to fit some kind of electric fan, otherwise you run the risk of boiling your engine, but suitable kits from the likes of Revotec can be bought for around £100. Or if you don’t mind getting your hands dirty you could always modify one from the scrapyard, but the beauty of the kits is that everything is included and it only takes an hour or so to fit. Follow along as Jon Betts shows you how.
The electric fan kits come with all fixings included as well as a thermostatically controlled switch, which can be adjusted to turn the fan on and off to suit your engine. You can of course add an additional switch to override this so that the fan can be controlled manually from in the car.
1. The fan kits come with everything required for a trouble-free installation. This is a 10-inch, heavy-duty fan designed to fit in front of the radiator and blow cold air through it. Fans can be supplied for fitting either in front or behind the radiator.
2. Before ordering your electric fan kit, you need to see what room you have. At the front of our engine, we were struggling for space and although the fans are slim it would have been too close to the water pump pulley, so we opted for a fan in front of the radiator.
3. As our kit was going in front of the radiator, we needed to remove this to gain access to fit the fan. The cooling system will therefore need to be drained by removing the lower radiator hose, as well as the top hose.
4. Once that has been drained, check how your radiator is fitted to your slam panel and then undo the fixings and remove it completely from the car. Take care not to damage the cooling fins.
5. With the radiator now out of the car, position the electric fan on the side that you want to mount it to. Make sure you consider any brackets or components on the car that the fan will need to clear.
6. The kits come with nifty little clips that pass through the radiator cooling fins. You also get supplied with some self-adhesive foam pads, which stick on to each corner of the fan to protect the fins.
7. With all four in place, turn the radiator over and then fit four more of the sponge pads, followed by the special locking tabs. Push these down as firmly as possible to ensure that there’s no movement in the fan.
8. Trim off any excess with a pair of snips and then repeat on the other three tabs. Once done recheck that the fan is secure and you are then ready to refit the radiator in the car.
9. Before the radiator can be refitted, you’ll need to remove the old mechanical fan blade. You may need to space the bolts which hold the pulley in place to take up the space of the missing fan blade unit.
10. The radiator can now be dropped back into your classic Ford and then secured in the usual manner. Double check that the fan is free to rotate and that it isn’t hitting anything else behind the grille or in the engine bay.
11. The kit comes with a thermostatically controlled switch, which requires this sender to be fitted into the top of the radiator. A silicone sleeve is supplied, which fits over the top outlet on the rad and then the capillary tube is fed into the outlet.
12. The groove on the silicone sleeve needs to go opposite the catch on the jubilee clip. Take care when pushing the hose into place so that it doesn’t dislodge the sleeve, and if the hose has gone hard or split consider fitting a new one to avoid any leaks.
13. The switch comes with its own bracket so mount this close to the radiator. We also used the fixing for the bracket to attach the earth wire from the motor itself. Make sure it has good contact with bare metal.
14. The blue wire from our fan unit connects straight to the NO connection on the switch; this is also the connection for an auxiliary dash switch if you are fitting one.
15. A fused, ignition-controlled positive supply is required for this particular fan, and as it is under 15 amps it doesn’t need a relay to be fitted. If one is required it will be supplied with the kit.
16. You can now mount the switch to the bracket using the washer and nut supplied and then install the dial, which will be used for adjusting the cut-in time of the cooling fan in relation to the engine temperature.
17. Refill the cooling system with the correct mixture of water and anti-freeze and then check for any leaks. If all is OK then start the car up and allow it to come up to temperature. Again check for leaks and retighten all jubilee clips once the hoses get warm.
18. You now need to allow the engine temperature to rise so that it’s midway between the normal running setting and the hot setting on your temperature gauge. Once it reaches the midway point, adjust the cooling fan so that it starts up. The temperature should now start to drop and eventually the fan will go off.
19. Once you’re happy that the fan cuts in at the right time, the dial can be secured down with the screw supplied so that it cannot vibrate out of adjustment. Allow the engine to cool down fully and then recheck the coolant.
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