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Quick to fit cooling products for your Race Car



Now the weather's warming up again, as always we have an influx of customers requiring products to help keep their engines cooler.

Here's a brief list (as the full list is almost endless) of some top products which you can use to try and keep your engine cool, starting with ones that require minimum work to do so.



The ‘go-to’ coolant additive when the coolant temp starts rising is Red Line Water Wetter. Whilst the name of it sounds odd, it’s one of our best selling fluids and racers swear by it. Water Wetter improves the ability of coolant to wet heat transfer surfaces by up to 50%. Basically, this provides better coolant contact in the cylinder head and reduces head temperature by up to 12°C. It improves heat transfer to the metal of the engine and doubles the wetting ability of the water. Works best in a totally water cooling system but can be used with glycol anti-freeze/water mix, though this does reduce its cooling ability. Red Line Water Wetter also reduces rust and corrosion and lubricates the water pump.

Go to - Red Line Water Wetter





Branded as a Davies Craig item but is actually made by Bosch, this little water pump is ideal for fitting into the heater hoses of your cooling system. If you are still using a conventional mechanical water pump, this pump can be used to boost the water flow around the engine and can then be left on after the engine is shut down to help prevent heat soak as the coolant temp can be known to creep up after the engine is shut down due to it not circulating.

Go to - Bosch Electric Water Pump



We sell both Tripac and Davies Craig fans here at Merlin. There really is nothing to chose between the two brands, albeit, Davies Craig make some sizes that we do not offer in Tripac. Both brands are slim line fit and both feature high quality Panasonic motors. Tripac are made in the USA, Davies Craig are made in Australia. These can be used to replace the mechanical viscous fan entirely or used in conjunction with it. These ideally fit behind the radiator and suck air through it, though they can also be fitted to the front of the radiator and blow through it (ideal for use in conjunction with a mechanical fan) but be careful not to block up the air flow through the radiator when doing so. We also sell fixing kits for both brands. You will also need some form of fan switch, which we have various options in abundance!

Go to - Electric Radiator Cooling Fans




We have a wide range of fan switches and controllers, everything from a basic switch at a set temperature to adjustable controllers. Note – some of these can be used to switch water pumps on too.


  • The first, cheapest and easiest method are these neat little switches from Setrab. They have an 1/8” NPT thread and switch at three different pre-set temperatures. These have a 16A rating so are suitable for switching fans, pumps, warning lights etc. These can be screwed directly into a port or can be used with our aluminium hose adaptors to go directly into a water hose. A relay may also be required.

Go to - Setrab USA Thermal Switch with 1/8NPT Thread


  • Another easy solution for fan switching is the Revotec electronic fan controller with an M22 thread. This is very handy, meaning the controller can be screwed directly into the radiator as a lot of radiators have an M22 threaded drain port in the base of them. This is adjustable, so the switching temperature can be set by the user. Supplied with a pre-built wiring loom with relay

Go to - Electronic Fan Controller With M14 Male Thread 


  • By far our best selling fan switch is the digital, adjustable probe type from Davies Craig. This has a stainless steel temperature probe which needs to be pushed through the fins of the radiator and can be set to the users preferred temperature. One down side to this option is that it does not measure coolant temperature, it measures the temperature of the radiator body. That said, we sell hundreds of these and they are very reliable. This can be used for one or two fans. Also available in the “premium” version which features a dashboard mounted display and a new gauge style display which is supplied with a mounting pod. 

Go to - Digital Thermatic Radiator Fan Switch (Adjustable)
Go to - Digital Premium Thermatic Radiator Fan & EWP Switch
Go to - Digital Gauge and Thermatic Fan/EWP Switch (Adjustable) 


  • Another really good way to switch your radiator fan on is to use the Revotec electronic fan controller for hose fitment. Available in a wide range of diameters to suit your coolant hose, this quite simply sits in the hose, once cut and measures the water temperature. The switching temperature can be adjusted by the user to suit your own requirements. A very popular, accurate, reliable way of fitting a fan switch.

Go to - Electronic Fan Controller for Hose Fitment




We also sell a wide range of air intake ducts and air ducting that can be used to duct air from the front or sides of the vehicle to vital components or to duct more cold air to radiators which are not in the cold air flow, such as rear mounted or boot mounted.

Go to - Air Ducting

Archived in: Cooling | radiator electric fan | cooling fan

28th May 2019