Cooling System Upgrade

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This page is created and researched by third parties completely unrelated to the company Davies, Craig. Davies, Craig at no time has had any input into this or related pages in the Holdenpaedia or Work Guides other than to lend assistance when required and supply the products. Davies, Craig is not currently and never previously been a sponsor of, nor asked for the guides/pages to be done. These pages and guides were all done by myself for my own interest and to try and curb some of the lies and BS that is on the net by parties with little to no current understanding or experience with these products. They were done to help interested members of the community see what is involved in installing these products and what they are capable of doing. At no time did Davies, Craig approach me and ask or pay for these pages to be done and at no time did they influence any of the results or comments. ReaperHR (Greg)
---- This page is a suppliment to the work guide for the installation of all of these products into a 1966 HR Holden:
The complete installation relating to this page

Further information for all of these products and more can be accessed from the Davies, Craig website:
Davies, Craig site

- ReaperHR

Cooling System Upgrade (Electronic):

This page is intended to compliment the work guide for the installation of a complete cooling system upgrade using Davies, Craig products. The guide and this page both refer to the following components:
  • Electric Water Pump (generation 3)
  • EWP Digital Controller
  • 14" Thermatic Fan
  • 12" Thermatic Fans
  • Thermatic Switch
With those 6 components load will be taken off the front of the engine through the replacement of the standard water pump, and the removal and replacement of the standard fan. These components will be replaced respectively with the Electric Water Pump (EWP) and Thermatic Fans. Controlling these electrical items will be the EWP Controller and the thermatic switch.

Below is a very basic image showing how the items are wired and placed into the system.
A basic image showing the general wiring of the replacement system.

===Electric Water Pump:===
The Davies, Craig Electric Water Pumps

EWP kit contents (Click to Enlarge)
The first item on the list is the EWP. These water pumps are designed to either replace or compliment the standard water pump in your cooling system. There are two standard pump designs, the EWP 80 and the EWP 110, the number in the name actually shows the litres per minute that each pump will push through the system at full throttle.

EWP80: Maximum flow rate of 80 litres/min.
- this pump is suitable for cars with engine capacity up to 5 litres.
EWP110: Maximum flow rate of 110 litres/min.
this pump is suitable for larger, high performance engines and 4WDs.

The EWP can be installed in one of three ways:

1) With Controller - The controller (mentioned below) will control the pump speed depending on temperature detected. The new digital controller will also display diagnostics on what is going on in the system. The standard water pump can be replaced with this setup. Another advantage is that with the new digital controller the EWP will have a run on of 2 minutes after the engine is shut off, helping it to cool and preventing heat soak and possible damage. This setup also allows you to adjust the system towards more power (cooler) or more economy (warmer).

2) With Thermatic Switch - Using the thermatic switch like you would for a thermatic fan the EWP will work as a booster pump, if the cooling system gets hot the thermatic switch will turn the EWP on at full throttle. This setup has the advantage that the switch can be plugged straight to the battery allowing the EWP to run on after shutdown if/when required. The disadvantage is that the standard water pump should still be used.

3) Continuous Running - Here you can wire the pump directly to the ignition, so when the engine is on the pump is also on (at full throttle), you'll need to remove the thermostat and the old water pump from the equation as this setup requires the ability to flow. Advantages are that there is no standard water pump in the system, much like point(1) above, the disadvantage though is that there is no control of the system, the EWP will flow at full speed at all times, this means slower warm up as well as the inability to tune the setup for power or economy. Considering though that this method is only really aimed at race cars or very hot engines that may not be an issue.

On this page and in the work guide I will be dealing with the recommended method outlined in point(1) above. My aim is to reduce any load on the front of the motor by removing the standard fan completely and by removing the standard water pumps functionality from the cooling system by using a shorter fan belt which will only go to the alternator, not to the water pump then the alternator.

Replacing Standard Water Pump with EWP and Controller:

Fan belt layout before and after EWP installation - Holden Red 6 (Click to Enlarge)
In preparation for installation of the EWP and Controller your cooling system will need to have the thermostat removed (it will no longer be necessary) and the standard water pump disabled (it is also no longer necessary). To disable the standard water pump you have a few options:

1) Remove the standard pump (You'll need to cover the hole with a plate and seal of some sort).

2) Remove the impellor from the standard pump and reinstall.

3) Remove the standard water pump from the fan belt drive train by using a shorter fan belt from the crank to the alternator pulleys alone.

With the setup I will be using here and in the guide I am using point(3) above and using a shorter fan belt that will no longer drive the old water pump. The water in your cooling system will not be impeded by the old impellor still being in place, it will flow through it. The diagram shown to the left shows the basic layout of how the shorter fan belt will be used.
Inlet and Outlet of the water pump marked with water flow - Red in, Blue out (Click to enlarge)

Wiring of the EWP with Controller (Click to Enlarge)

The next step is to install the EWP. The EWP will need to be mounted in as low a point as possible to maximise the advantage of gravity in feeding the pump from the radiator and to also minimise the chance of air getting into the pump. To this end the lower radiator hose is ideal. Firstly compare the design of the pump to the shape of the bottom radiator hose and then look at the available space to choose an effective mounting position. The EWP will not need a bracket to support it, it is lightweight and can be supported solely by the radiator hose, it is infact better to not have the EWP rigidly mounted (i.e. to a bracket) so that it can move with the engine when it is working (which is why rubber radiator hoses are used on engines). Be sure however to mount it in the correct orientation, it has a drain boot at the back which needs to be pointing downwards (instructions are in the manual on how to change it if need be) and it needs the inlet facing the outlet from the radiator and the EWP outlet going to the inlet of the motor.

Once you have a mounting point and orientation of the pump organised you can then modify your radiator hose to suit. Generally I've found you can modify the bottom radiator hose to take the EWP by simply cutting the whole center of the hose out and replacing it with the EWP assembly. A few inches of hose at both the inlet and outlet of the EWP can then be used to attach it to both the motor and the radiator.

==== Bleeding the EWP of air ====
Bleeding the EWP of air (Click to Enlarge)
  After choosing a mounting point and attaching the modified radiator hose to the EWP you can install it. It does however need to be bled of air. The image to the left shows a method of mounting the EWP temporarily at a "kicked back" angle to allow trapped air to escape from the assembly.  The following steps are required to bleed the EWP:

1) Fill the cooling system with coolant.

2) Hard wire the EWP directly to the battery (blue to positive, black to negative), this will enable the EWP to run at full throttle without the need to run the engine of the car).

3) Run the EWP for 5 to 10 minutes with the radiator cap off to be sure there is no trapped air in the system. Watch the coolant level and top up as necessary.

4) Once the bleeding procedure is complete remove the wiring from the battery and return the EWP wiring to the standard position (in this case rewire it back into the controller wiring).

==== Warnings ====
These warnings come directly from the instructions for the EWP: 
  • Do not run pump dry as seal damage may occur and your warranty will be void.
  • Engine temperature must be monitored very closely at all times but especially immediately after installation and until pump operation and capacity have been proved.
  • Use of the EWP® after removing the pump impeller or deleting the mechanical pump pulley from the belt system will increase maximum engine speed.  Running an engine at higher speeds than normal may affect other engine components.
  • The EWP® can handle most rust particles and sludge found in cooling systems but large rust particles should be flushed from the radiator before the EWP® is installed.
  • Some vehicles may require special bleeding procedures to remove air from the cooling system not described here. The EWP must be completely flooded with coolant at all times to achieve the life specification of the EWP and to preserve warranty.
  • Do not use the vehicle's engine management system or wiring connected to the vehicle's engine management system as an ignition source because it may cause failure of the management system and/or the electrical system. The ignition source must be a steady positive supply of 12- 14VDC.
  • Vehicles with both heater circuit inlet (return) and outlet ports in the mechanical pump housing will suffer reduced heater performance unless the heater return position is relocated (suggest top radiator hose).
==== Recommendations ==== These Recommendations come directly from the instructions for the EWP:
  • If an EWP is installed on a vehicle which is kept in storage for more than a month, (e.g. a show or race-car), it is advised that the pump be operated for approximately 5 mins constant running every month. This will minimise the build up of any sediment in the EWPâ„¢ and also lubricate all parts within the pump.
  • For improved heater performance on vehicles which have the heater inlet (return) and outlet ports in the mechanical pump housing (referred to in "Warnings"), Davies, Craig has developed the Electric Booster Pump, EBP", which fits into the heater hose and boosts flow through the heater circuit and/or cylinder heads. There is more information on our web page ( )
  • LPG (Liquid Petroleum Gas) vehicles require constant flow through the LPG converter and if the EWP® is used in conjunction with the Controller, we recommend the installation of an EBP® (Electric Booster Pump) to overcome freezing of the converter body at start up.
  • It is recommended that the cooling system is flushed every 6 months or 10,000kms to remove any built up sediment in the cooling system.
  • If you fabricate metal hose adapters to replace the plastic ones supplied, be sure the bolt holes match those on the pump body precisely, because tightening bolts through misaligned holes may tend to pull the two halves of the pump body apart.
IMPELLER TIP CLEARANCE: The impeller tip clearance is very tight for maximum efficiency, and may when new actually scrape the pump housing causing a slight noise. The impeller will bed in over time and the noise cease.

==== Specifications ==== The following specifications come from technical information supplied on the Davies, Craig website.

===== EWP 80 =====
Specifications - EWP 80 (Click to Enlarge)
 Operating Voltage: 4V DC to 14.5V DC
 Maximum Current: 7.5A
 Flowrate (Max.): 80L/Min at 13.5V DC
 Operating Temperature: -20C to 130C
 Pump Design: Clockwise centrifugal with volute chamber
 Motor Life: 2000 hrs continuous at 80C and 12V DC
 Pump Weight: 900g
 Pump Material: Nylon 66, 30% glass filled
 Burst Pressure: 50psi (Minimum)
 Max. Radiator Cap Pressure: 29psi
 Fits Hose Sizes: 32mm to 51mm (1-1/4" to 2")

===== EWP 110 =====
Specifications - EWP 110 (Click to Enlarge)
 Operating Voltage: 4V DC to 14.5V DC
 Maximum Current: 10.5A
 Flowrate (Max.): 110L/Min at 13.5V DC
 Operating Temperature: -20C to 130C
 Pump Design: Clockwise centrifugal with volute chamber
 Motor Life: 3000 hrs continuous at 80C and 12V DC
 Pump Weight: 1020g
 Pump Material: Nylon 66, 30% glass filled
 Burst Pressure: 50psi (Minimum)
 Max. Radiator Cap Pressure: 29psi
 Fits Hose Sizes: 32mm to 51mm (1-1/4" to 2")

=== EWP Controller ===
The New Digital EWP Controller (Click to Enlarge)
To control the flow rate of the water pump and desired temperature target for the system we will need an EWP Controller.
EWP kit contents (Click to Enlarge)
The new digital controller was recently released and after seeing how reliable the old unit was on my other car I jumped at the opportunity to try out this one. The new digital controller includes many new features including:
1) Temperature target setting by one simple button.
2) Electronic temperature display.
3) 2 minute in-built run on when engine switch off.
4) More attractive appearance.
5) Self (and cooling system) diagnostic ability.
6) Warning light  
EWP Controller Wiring Diagram (Click to Enlarge)
==== Installation ==== The EWP Controller is to be installed inside the passenger cabin of the vehicle, necessary wires can pass through the firwall into the engine bay. The new controller can be installed in a position where it is visible so that you can see the lights indicating temperature and water pump state or you can hide it and instead display the warning light wherever you wish. I personally made the controller visible and am now using it to replace the unreliable temperature gauge in that vehicle. If you so wish though you could hide it in a position where you will only need to see it if the warning light alerts you, the warning light of course should be placed in a position that will catch your attention like the dash or console for instance.

===== Mounting the Sensor Probe =====
Mounting the controller sensor into the thermostat through the upper radiator hose (Click to Enlarge)
With the new digital controller there are now a few methods available to mount the sensor, the original method of under the seal of the upper radiator hose and down into the thermostat housing and engine or a new method where-by you can drill and tap the thermostat housing and mount the sensor into a supplied fitting there. Either method is fine and works well but I used the original method of running the sensor under the lip of the upper radiator hose because I haven't had a problem with that method before.
Mounting the controller sensor into the thermostat through the upper radiator hose (Click to Enlarge)

===== Mounting into the radiator hose (Original Method) ===== The two images shown here display how I mounted the controller sensor wiring and also an image from the instruction booklet showing the same thing. The steps for the original method are as follows:

1) Remove the upper radiator hose

2) Remove the upper portion of the thermostat housing

3) Test fit the sensor wire to see how it will sit

4) Wrap the supplied copper wire around the sensor probe and wire as required to get it to sit in the housing. The copper wire will support the probe and wire and stop it from being pushed out of the hosing by coolant flow.

5) Install the sensor wire through the upper portion of the thermostat housing and down into the lower thermostat housing. I actually push mine down into the block to be sure I am getting a good temperature reading.

6) Place the sensor seal over the upper portion of the thermostat housing where the sensor wires will run and where it will be covered completely by the upper radiator hose. You can support it with a strip of electric tape if required.

7) Run the sensor wire over the sensor seal (and the twin wires through the two grooves in the seal) making sure that the heat shrink after the two separate wires will remain free of the seal.

8) Support the probe wiring and seal as you push the radiator hose over the top and seal it all with the hose clamp.

===== Mounting into the thermostat housing (Recommended Method) =====
Mounting the controller sensor into the thermostat through the upper radiator hose (Click to Enlarge)
The new digital electronic controller includes fittings to enable you to mount the sensor directly into the thermostat housing, you'll need a 1/2" and 9/16" AF spanner, some thread tape, a suitably sized drill (11mm or 7/16") and a 1/4" BSPT tap and a tap handle makes the job easier. This is the recommended method for mounting as a seal is more easily achieved, but firstly make sure there is enough metal in the housing to accept the fitting (minimum of 3mm). The method for installing it are shown in the image and also follows:

1) Mark the location on the thermostat housing where the fitting will be installed. The top of the dome is recommended.

2) Make sure the housing is supported (and off the car so that metal shaving don't go down into the block) and drill the hole.

3) Tap the hole enough so that the compression fitting will just protrude (this type of fitting is angled to get tighter as they are screwed in). Stop often to check the fitting in the hole to meet this condition (see the digram).

4) Put some thread tape on the fitting and screw it into the housing.

5) Put the upper part of the compression fitting over the sensor wire (thread tape it first too) so that it will be screwed into the lower fitting when it goes together. Put the sensor wire through the lower mounting and into the housing so that it will be in the coolant flow. Next hand tighten the upper portion of the compression fitting into the part screwed into the housing. Finally support the lower portion of the fitting with the 9/16" spanner and tighten the upper portion 1/4 turn with the 1/2" spanner.

==== Advantages ==== The new controller allows you to specify a target temperature for the system through the use of one button. The system will then try to reach and maintain that temperature through voltage regulation to the electric water pump directly affecting its flow rate. The new controller also includes an in-built 2 minute run-on after engine shutdown. During this time the controller will run the electric water pump as necessary to cool the engine, it will continue doing so until the 2 minutes is up or the engine temperature reaches 5 degrees celcius below the set temperature. Used in conjunction with Davies, Craig thermatic fans this is a very effective method for reducing the chances of heat soak and possible damage to the motor.

Another improvement of the new controller is that it can display diagnostics for the cooling system as well as for itself. If there is a problem detected you'll now have a fair idea of what is going on in the system. The chart is displayed below:

As you can see the controller will detect and display a warning sequence for many varying possible problems with the cooling system from wiring issues to its own microprocessor. The red Test light or warning light will give you ample warning of a problem being detected and also allow you a starting point for where to look at problems. The warning at the bottom of the image also states however that with temperature related issues the problem may be caused by an external problem to the Davies, Craig system, for instance low coolant, pinched radiator hoses, fans non-functional etc

==== Functionality ====
Electric Water Pump operational curve when used with EWP Controller (Click to Enlarge)
The Electric Water Pump is not an on/off device when used in conjunction with the EWP Controller. The Controller detects engine temperature and then guides the pump in what is necessary to get that temperature to the set temperature and keep it there. This is done through varying voltages which in turn varies the flow of the pump itself. This chart shows the operation of the electric water pump when controlled by the Controller.

As you can see the controller will allow the car to warm up faster by not operating the pump until it is within 20 degrees of the set point. The set point on the graph is whatever temperature you have decided to keep your engine at, it can range from 75 celcius to 95 celcius. At 20 degrees below the set point the controller will start the electric water pump in a pulsing mode, at 5 volts the pump will be on for 5 seconds and then off for 5 seconds repeatedly. This will help slow the raising temperature of the engine without halting it. At the set point full voltage is supplied to the pump. It is also worth noting here that any thermatic fans should be set to come on at 5 degrees celcius above the set point, to help the cooling system maintain that temperature without the fans fighting the controller to maintain a specific temperature setting.

Another thing I found while doing the work guide was that it was actually hard to get the coolant to go above the set point. The water pump was so successful at maintaining that temperature that I had to unplug it to let the temperature go up before I could set the fan starting point. I can't think of any other method of cooling for a car that is this reliable at keeping an exact temperature while the engine is running, whether stopped, idling, jammed in traffic or cruising down the highway.

EWP Controller LEDs (Click to Enlarge)
The following information explains the functionailty of the LEDs in relation to the water pump operational curve graph shown above.
LED Names, Colours and Function
Name Colour Description Function Defined
Temperature Green 75C LED Flashing Temperature is currently below 75C
Temperature Green ON Temperature is currently the lit LED level.
Power Amber ON Controller has power.
EWP Green OFF EWP is OFF (Area A)
EWP Green Flashing EWP is in pulsing mode (Area B)
EWP Green ON EWP is running between 5V and full (Area C)
Test Red ON Warning has been triggered, see diagnostic chart
Remote Test Light Red Flashing Notifies that the Test light is on
Note: When the controller is run-on mode the temperature will be shown with the lit green temperature light, the power light will flash and the EWP light will remain on, the pump will also run at full voltage.

==== Setting the Controller ==== The new digital EWP Controller uses a single Set button to allow you to specify a temperature you would like the pump to try and maintain in the cooling system. From the factory the controller is set at 85 degrees celcius, but using the Set button you can change this to 75, 80, 85, 90 or 95 degrees celcius. Basic instructions in how to use the set button to change the set temperature are outlined here:
1) Pressing the Set button once will show the currently set temperature with an amber LED.
2) Hold the set button down, this will scroll through each of the temperature settings, once you reach the desired temperature release the button.
3) The LED will then start to flash, to confirm the setting hold down the set button for 2 second. If the setting is not confirmed in 5 seconds it will revert to the old setting.
4) Check the set position by repeating step 1.

As mentioned earlier a warmer temperature is more for economy while a cooler temperature is more towards power, I personally set mine to the middle (85 degrees celcius) and it runs well.

==== Warnings ====
These warnings come directly from the instructions for the Digital EWP Controller:

-    Engine temperature must be monitored closely at all times but especially immediately after installation and until pump operation and capacity have been proved.

-    Do not use the vehicle's engine management system or wiring connected to the vehicle's engine management system as an ignition source because it may cause failure of the management system and/or the electrical system. The ignition source must be a steady positive supply of 12-14VDC.

==== Recommendations ==== These Recommendations come directly from the instructions for the Digital EWP Controller:

-    For improved heater performance on vehicles which have the heater inlet (return) and outlet ports in the mechanical pump housing (referred to in "Warnings"), Davies, Craig has developed the Electric Booster Pump, EBP*, which fits into the heater hose and boosts flow through the heater circuit and/or cylinder heads. There is more information on our web page

-    LPG (Liquid Petroleum Gas) vehicles require constant flow through the LPG converter and if the EWP" is used in conjunction with the Controller, we recommend the installation of an EBP* (Electric Booster Pump) to overcome freezing of the converter body at start up.

=== Thermatic Fans === Thermatic fans are now a common addition to modern vehicles, they are cheap, they are reliable, they can be placed virtually anywhere and they take weight away from the front of the motor allowing it to rev more freely. The Davies, Craig thermatic fans are one of many brands on shop shelves but they are also one of the most trustworthy. The fans I bought years ago for my car have worked faultlessly since the day they were installed and the design has since been upgraded making better again.

For the HR (and likely earlier) the 14" fan is big enough to go infront of the radiator without having to be modified for being too big (the 16" however WILL have to be modified to fit). Behind the radiator you will only be able to fit fans if you are removing the water pump (like you will be if you are installing an electric water pump like I am). If the water pump is being replaced with a cover plate then you may have the option of fitting a 14" fan behind the radiator also, if however you are leaving the water pump intact and only removing the belt hub then you will be able to fit two 12" fans with modification or likely two 10" fans without. A large fan will move more air than two far smaller fans.

==== Choosing a Fan ==== The question you need to ask yourself (with an older car) is whether you want fans on the back of the radiator as well as the front, if so then I'd recommend going the same size fans front and rear so that you can use the opposite fans mounting points. Naturallyon pre-HR era Holdens this would limit you to four 12" fans or four 10" fans. If however you will only be going for fans on the front of the radiator I'd recommend going for a fan as large as possible, i.e. the 14" fan. On post-HR era Holdens the motor has a lot more free space between the radiator and the water pump, this would enable you more choices of size and configuration, you will need to measure your radiator, measure your free space and then go to the davies craig website and check the sizes of the fans you would like to use.

Below is a chart from the Davies, Craig website showing recommended fans and applications for many Holdens.
Davies, Craig Fans for Holdens
Model Condensor cooling only Additional cooling only Radiator cooling only
NOVA 1.6/1.8 DCSL10 DCSL10 DCSL14

The chart below gives specifications for the most common fans from the chart above. 
Davies, Craig Fans for Holdens
Model Max. Current (at 12 volt) Life Weight Overall Width Overall Height Leg Spacing (Width) Leg Spacing (Height) Leg Block Depth (Motor) Depth (Shield)
DCSL10 7 Amps 1500 Hrs at 80 deg C 1.13kg 290mm 270mm 201mm 201mm 145mm 64mm 30mm
DCSL12 9 Amps 1500 Hrs at 80 deg C 1.45kg 293mm 293mm 222mm 222mm 148mm 51mm 36mm
DCSL14 11 Amps 1500 Hrs at 80 deg C 1.50kg 348mm 350mm 260mm 260mm 185mm 76mm 40mm
DCSL16 19 Amps 1500 Hrs at 80 deg C 3.01kg 424mm 400mm 328mm 328mm 208mm 100mm 44mm
DC31 11 Amps 1500 Hrs at 80 deg C 1.50kg 349mm 349mm - - - 80mm -
Fan Size Chart
DCSL 10 -16 DC31
<img longdesc="/possible-070707/index.php/Image:FanSize.JPG" src="" alt="Image:FanSize.JPG" width="418" height="276" /> <img longdesc="/possible-070707/index.php/Image:FanSize2.jpg" src="" alt="Image:FanSize2.jpg" width="381" height="226" />
 ==== Installation ==== ===== Fan Orientation =====
Message designating which way the blades should face (Click to Enlarge)
The fans as supplied from Davies, Craig are designed to go upstream (in front of the radiator), if you should wish to place them downstream (on the engine side of the radiator) you'll need to take the blades off the fan by removing the hex nut or clip and flip them over, then resecure the blades. Always check the fan blades when flipping them over as they are marked on the faces "This side to front" and "This side to back", if you follow that correctly the fan blades will be correctly orientated.

Next after flipping the blades you will also notice on the blade that they are marked with a small arrow, this arrow shows the correct direction for spinning, when wiring the fans up check they will spin the correct way. For instance, if you have the fans wired blue to blue on the relay wires and black to black on the relay wires and the fan is spinning the wrong way then swap them, blue to black on the relay wires and black to blue on the relay wires. This will make the fan spin in the opposite direction when engaged.

===== Fan Mounting ===== The Davies, Craig Thermatic Fan kits come with bolts that will be long enough to go through your radiator and leave a fair length to play with on the other side. If you are mounting fans on the front and back of the radiator it is therefore far easier to get the same sized fans and mount the two using the same bolts. The kits also come with plastic legs which can be put into various supplied positions on the fan to supply you with options on mounting position.
Mounting of a thermatic fan

Spacing the fins in preparation for mounting the bolts (Click to Enlarge)

The image shown here demonstrates the use of the bolt through the radiator for the mounting of a single fan. To push the bolt through the radiator you first need to space the fins between the pipes to allow a free space for the bolt to slide through. I usually use a small flat bladed screwdriver first, pushing it through the hole in the leg on the fan then through the radiator between the fins. Next I use a bigger flat bladed screwdriver and then finally a phillips screwdriver with a similar shaft diameter as the bolt. Once the hole is carefully made you can then push the bolt through and begin securing it. I place all four bolts however before I begin tightening any more than hand tight. Be careful to support the radiator properly while doing this as if it drops or falls over you may do damage.

===== Wiring Diagrams ===== The Davies, Craig thermatic fans are designed to be effective under many different scenarios, below are shown 6 different wiring schemes to suit various applications and configurations these fans can be used in.
Thermatic Fan Wiring Diagrams

==== Trouble Shooting ==== The following notes are designed to help you overcome the most common problems experienced by customers with Thematic Fans:

a.  Correct model is fitted.
b.  Thermal Switch is set correctly.
c.  Fan blade facing the right way and rotating in the direction of the arrows or in accordance with chart.
d.  Fan/s connected to full 12V power source.
e.  Fan too far from face of radiator.
f.  Other cooling system problems.

a.  Adjustment of thermal switch.
b.  is the vehicle towing?
c.  Other cooling system faults.

a.  Fuses.
b.  Adjustment of thermal switch -set too high!
c.  Wiring integrity.
d.  Connect motor(s) directly to battery then trace wiring towards switch if motor(s) runs.
e.  Check earth connections.

=== Thermatic Switch === The thermatic switch is what controls the flow of power to the fan(s), through a temperature probe installed into the upper radiator hose the thermatic switch can be forced to switch the fans on and off via a knob control set by the owner.

==== Installation ==== The thermatic switch can be installed virtually anywhere in the car close to the radiator, as long as you can reach the controlling knob during setup time and the switch probe can reach into the cooling system. The switch probe is installed in much the same way as the EWP Controller probe, it however runs into the radiator end of the upper radiator hose, steps are below:
Installation of the sensor probe (Click to Enlarge)
1) Remove upper radiator hose.
2) Straighten probe wire.
3) Place switch probe seal onto radiator at joining point.
4) Place the switch wire in the groove of the seal.
5) Secure seal and wire with some electric tape.
6) Replace upper radiator hose being careful to not knock the probe seal out of position.
7) Reseal upper radiator hose with clamp.
8) Fill the system with coolant
9) Test run the engine and when it gets to the temperature you want the fans to turn on, turn the knob on the control switch until they do.
The thermatic switch will take an ignition source and will supply up to two fans. Remember though that fans will not necessarily be mounted blue to blue and black to black with the switch, double check fan direction when they are engaged and wire as necessary to get them turning in the correct direction.

== Final Notes == === Equipment === ==== Electric Water Pump ==== As ever the electric water pump is doing an excellent job on this car, and the one that was installed ages ago on my other car is also still performing perfectly.
==== Controller ==== The new digital controller is more than a step up from the old, even though my old one is performing as good today as the day it was installed I am still going to replace it with a new digital one simply because it is so much more informative. The temperature indicators and diagnostic sequences are really a must have.
==== Thermatic Fans ==== Both the 12" and 14" fans perform excellently, on this vehicle the have been engaging for around 10 - 20 seconds at a time before the temperature drops back to the level where I want it. In conjunction with the EWP they barely ever engage and when they do it is not for long due to how well they cool the system.
==== Thermatic Switch ==== As ever the thermatic switch is reliably controlling all of my fans. Both cars use these Davies, Craig switches to control the fans and neither has a problem. Sealing the probe can be a minor problem but as long as you take care installing it you should be able to achieve a good seal over the wire with a minimum of fuss.
=== Performance === ==== Power ==== Both cars these setups are installed on are fairly stock 186ci engines along with 2 speed powerglide transmissions, so neither is obviously a high performance vehicle. Power however seems to be very mildly improved. The main advantage however seems to be in torque and at higher speeds. It was especially noticeable on this second car how much pickup was gained between 80km/h and 100km/h (I don't go over 100km/h in that car) where before it was a bit of a slug at these speeds now it really has a very noticeable improvement. Not only that but the engine seems to want to push even harder and go faster. Changing lanes and over taking on the highway is definitely not a problem. Torque up hills is improved also, the engine seems to go up a hill a lot more easily than it used to.

==== Economy ==== Both cars have been tested for economy, the first vehicle is set up mainly for highway driving (only when compared to the second vehicle) and the second vehicle is set up for start stop city driving.

Vehicle 1: 2 speed powerglide auto, 3.36 diff, 14" wheels
Vehicle 2: 2 speed powerglide auto, 3.55 diff, 13" wheels, engine in desperate need of reconditioning

On the highway the first vehicle nets us between 27mpg and 30mpg even when overloaded with kids and holiday baggage. It doesn't get driven enough in start stop driving (or enough at all) to do any testing in that department.

The second vehicle doesn't do much highway driving (with a 3.55 it revs too hard to get good economy anyway I believe) but in start/stop driving with its clapped out motor it has gone from 19mpg to 21mpg, it is still being tested however.

=== My Views - ReaperHR === Since installing these products on my first car I have been nothing but impressed, the control over engine temperature is astounding, within 5 degrees celcius either side of your set temperature is held perfectly at any time. After installing you can feel the improvement in revving of the motor, it feels so much more free that it's hard to describe the difference.

With todays fuel prices and the advantage in economy both vehicles are gaining these products will pay themselves off in only a few years. That doesn't take into account the extra care they are taking of the motor too by maintaining a temperature perfectly and by eliminating heat soak once shut off. Personally I couldn't be happier with the products and their performance on both cars, if I had more cars I'd be installing these kits on each and every one.

The second car was completely original (other than electronic ignition) before this kit was added but I had no hesitation in adding it, the gains are well worth the time and cost of the installation and products and even with all of these products installed the car still has a fairly original look in the engine bay and the upgrades are completely unnoticeable with the bonnet down. The added bonus of course for the person thinking of keeping a classic original is that when removed the car can go back into original condition with no real modifications.

I also cannot rate the service of the Davies, Craig personnel any higher, of all the companies I have dealt with they have been the best by far. I've had companies jack up the price of products on me at the last minute, lie to me about requirements, snub me once the products have been bought, refuse to even reply to queries etc but never once have I had a problem with Davies, Craig. Every time I have had a query it has been answered within a few days, sometimes within a handful of minutes. I would never hesitate to buy their products over anything else on the shelf and I don't hesitate to recommend them over anything else that is out there. A more professional and courteous company I have never dealt with, especially in Australia where our companies seem to have the idea that the customer and their opinion is not a concern.

=== References === Information for this page was gathered from the following sites:
Davies, Craig site
ReaperHRs Shedand from the following books:
Electric Water Pump instruction booklet
Electric Water Pump Controller instruction booklet
Thermatic Fan instruction booklet
Thermatic Switch instruction bookletand from the following members personal experiences:

Work Guides for the installation of these products can be found here:
Electric Water Pump Installation (First Car)
Turbo Timer Installation (Not necessary with digital controller)
Thermatic Fan installation (First Car)
The complete installation relating to this page


Coolant Recovery System

Filling The Radiator

Coolant Heated Inlet Manifolds

Cooling System Upgrade  



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