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By Brian Richards
This article is provided for your personal use - Copyright remains with Brian Richards.
NOT to be reproduced or copied without the express permission of the Author
(also seen in "Sidescreen" & reproduced courtesy of Brian and Editor Bob Slender)
This mod cannot be applied to a TR2/3 as you require the full width between the inner guards. Also it is not possible with the original steering box.
Also see the article on repairing a LEAK in the sensor plug in plastic tank Volvo radiators.

I decided to fit a new radiator after many problems with the original one with leaks and marginal performance on the track. It performed fine on the road but was stretched on a hot day on the track. Also I needed a new water pump as my $10.00 ex wreckers pump purchased three years ago, was leaking.

After much investigation I decided on a Volvo 240/244/740 cross flow unit. I was able to obtain a leaking unit from the wreckers free to use as a template.

My car is fitted with rack and pinion steering so I could move the radiator forward. The Volvo radiator is almost the full width between the inner guards so it would foul the steering box if so fitted. When fitted, the bottom of the new radiator is level with the floor of the air inlet of the front apron. As such I was able to fit my oil cooler where the lower part of the old radiator would normally be. This is mounted to the rack and pinion mounting cross bars.

Click Pic to View

The water pump (Davies Craig Electric Water Pump) is attached under the cross brace on the LH side and connected to the radiator outlet utilising the original TR tube and bottom radiator hose. These are mounted horizontally.

I made up a simple frame for the bottom radiator support and utilised the Volvo lower rubber mounts. This frame was bolted to the original TR radiator mounting points. I fabricated a similar mount for the top and this is held in place by a central vertical brace from the lower frame and two rear braces similar to the original two used on the TR.

These pics give some more details
about the location of the radiator
compared to the original steering box mounts.

Click Pic to View

The block outlet is by way of a fabricated elbow (see picture) and half a top radiator hose from an 86 Laser. The other half is the same so I get a spare.

Thermostat was removed and an off the shelf hose (Magna I think) was used to connect the thermostat housing to the water pump.

As the radiator is a cross flow unit without an effective top tank, I fitted a TR7 remote tank to the front apron cross brace. Its outlet was connected to the fill line on the radiator and the vent line also connected.

I maintained my coolant recovery tank. There is no problem with filling the system and it only requires one small top up before it's full.

This photo still shows the original thermostat housing in place.

This photo isn't at 90°!
It is looking forward from the
passengers side of the car.
Click Pic to View


After I made all the required fittings I took my ‘free' radiator to a repairer to see if it could be fixed. "No" - it was beyond repair. A new one was only $360.00. I could have got a brass one or an aluminium one. The repairer recommended the brass one which is what I ended up with.

I fitted a Davies Craig Electronic Controller to regulate the temp as the thermostat is removed. This works by controlling the voltage to the pump. Until the temp gets up to about 50C, there is not current to the pump. After that it starts to apply short pulses to get the coolant moving. As the temp increases a steady voltage is applied and so more coolant is circulated. If the temp drops the voltage is reduced. This can mean that you can actually be getting full coolant flow while the engine is idling or in traffic and conversely low flow at speed. The coolant flow is therefore regulated depending on engine requirements rather than engine speed.

The control unit is mounted in the cabin on the rear of the brake/clutch master cylinder housing.

To allow for adjustment of the alternator belt (a thin one on mine) I mounted a small jockey pulley from an early Barina air con unit to the front engine plate slightly above and to the right (driver's side) of the crank pulley.

Performance is great with temps steady at 81°C in hot traffic, expressway, and on track it does rise to about 90°C but this should drop according to Davies Craig after I make a small mod to the controller to increase its sensitivity.

In total this cost me in the order of $765.00 plus my time. ($360.00 Rad, $190.00 water pump, $155.00 Controller, $30.00 hoses, $ 30.00 misc). If you discount the cost of a new water pump and the required radiator repair, it was not too bad.

To carry out this mod there were no changes made to the car (holes, brackets, etc) and the original parts can be refitted at any time.

This mod can not be applied to a TR2/3 as you require the full width between the inner guards. Also it is not possible with the original steering box.