Engine Cooling

In any liquid cooled internal combustion engine, the regulation of the temperature within the engine block is controlled by the thermostat which regulates the cooling liquid flow on demand from the engine itself.

Any fan system filled externally within the cooling system is designed and positioned to provide additional ventilation to the radiator itself. Up to the early Sixties, little thought had been given to the implications of having a permanently coupled fan whose speed was a direct function of the engine itself.

An enlightened company called Kenlowe designed a range of electric fans which were controlled by a separate thermostat located within the radiator hoses, switching the fan on and off as required to maintain the optimum water temperature.

Viscous fans were another variation, as were variable pitch fans. In these systems, as the engine speed increased, both became redundant within the primitive engine management systems that prevailed at the time. The forward motion of the vehicle achieved engine cooling.

Radiator muffs were used in winter to stop cold air entering the engine and help it warm up.

For interest, above about 25mph, there is an excess volume of air due to the forward motion of the vehicle to maintain engine temperature. The fan is completely unnecessary. Ford actually designed the radiator grille for later model Cortinas and Granadas, which formed an air dam above 30mph to assist with this issue.

Not having the additional cooling effect of a fixed fan also has several others advantages.
Engine warm up is much quicker, with a consequent reduction of fuel consumption particularly in winter

Noise levels are also reduced, but particularly much power taken from the engine is saved.

Any engineer with experience in mechanical power transmission or air conditioning will confirm that air itself is the most difficult and costly commodity to move.

On an Anglia, I have calculated that about 3bhp of engine power is required just to move the fan when the engine is running at 4OOOrpm. This represents about 7.5% of the engine power output, quite a lot when you only have 39bhp to play around with anyway.

With particular reference to Anglias however is the absolute fact that all Ford engine blocks of the period were identical in design, be they required for 997cc or 1500cc engines. The large engine must generate more heat than the smaller internal swept volume capacity unit. They all have the same water capacity. Many use radiators, all of which were designed to cater for the worst case of heat generation, ie the large capacity engines.

It follows that the small engines are overcooled and this is exactly the experience with my 997cc Anglia even with its mild tuning equipment, which uses a twin-choke Nicki carburettor and branched exhaust manifold. We drive the car quite hard. It only overheats in the highest summer ambient temperatures, so I replace the fan for July and August. Another point is to realise that the Ford original equipment temperature gauge is inaccurate and only has a five degree range between cold and hot.

As car design has progressed in the last 15 years, the primary quest has been for improved fuel consumption. This has been achieved by petrol injection systems, and also by the most successful engine management systems, so that fuel is burned most efficiently. There are no cars now have fixed fan cooling for their radiators.

Take the fan blades off your Anglia, which incidentally has a larger cooling system water capacity than a 1500cc Ford of the time. You will notice a reduction in engine noise, an improvement in performance, an improvement in fuel consumption and quicker engine engine warm-up times.

Replace the fan only in hot weather, or if you anticipate that you may become stuck in traffic jams in the summer. If the engine does start to overheat when the fan is not fitted, switch the heater controls to hot, the air vent to demist, switch on the heater fan, open the windows and watch the temperature gauge fall. This is because there is additional water capacity in the heater system, which includes another small radiator where heat can escape.

Go on, give it a go! This is a NO COST modification that really does work..

MELANIE POWELL, GREAT WITLEY, WORCESTER.

Thanks for that tip, Melanie, something that everybody can do without having to spend any money However, if you are in any way unsure about your cooling system, it's best not to try this, just in case. We don't want a load of overheated Angilas by the roadside, it's not good pubilcity for the cars! However, if you've got an Anglia that runs cool most of the time, give it a try, although take your fan blades and a spanner with you on the first few journeys, just in case! Ed.

Replys

COOLING DOWN

Dear Ed,
I enjoyed Melanie's letter last month which gave some very useful tips to get more power and economy by eliminating the air drag of a fan, which goes up with the square of engine speed.
However, two points.
a) The blocks of 997cc, 11 98cc and I 598cc are not all the same. The smaller two have a three bearing crank, not five, and the capacity is increased by increasing stroke, so the 1500 block is about one inch taller than the 997. This is why the exhaust doesn't fit straight if you put the big one in.
b) The risk of overheating is too big a price to pay for not doing a properly engineered mod and replacing the fan with a thermostatically controlled electric one, which comes on only when needed. Even a manual switch on the dash would avoid taking spanners everywhere.
Hope this avoids armies of broken down Anglias next summer.
Regards,
WARWICK FORTESCUE, BRISTOL.

STILL COOLING DOWN
Sir,
I read with interest and some trepidation the article concerning removing the engine driven cooling fan on the Anglia. Ajoke, surely? OK, being cast iron the Anglia engine is far less likely to suffer serious damage due to overheating than an alloy version, but why risk serious damage?
I had some experience of the kenlowe fan. I converted my 1966 Morris Cooper S, to a Kenlowe fan in the 1970s. My experience was good. The fan provided more than adequate cooling on this 5hot" A­series engine. The only real problem was the fan motor's current drain. The fan consumed 8A, and, as the charging circuit was powered by a dynamo (20A max), it meant that when you were sat in traffic you had to slightly rev the engine to obtain the necessary charge to allow enough cooling - somewhat defeating the object of the exercise. This may also be a problem with the dynamo charging on the Anglia. there was another company called Wood Jeffrey who made a similar set-up to the Kenlowe product. The main difference being the type of temperature sensor used and its positioning. The big question is are these companies still in existence today - I doubt it.
I fully concur with the statement that the Anglia temperature gauge is inaccurate - has anyone ever had the needle pointing to normal on the centre of its scale? The answer to loss of power due to the engine driven fan is to fit a higher temperature thermostat, together with a higher pressure radiator cap. As long as the coolant does NOT boil, the higher the temperature, the higher the efficiency of internal combustion engines.
Cheers,
GRAHAM BIRKS, BY E-MAIL.

P.S. Further to my e-mail, a casual surf of the Internet revealed that Kenlowe are still in business, mainly producing cooling fans for industrial uses. However, they still have a range of car cooling fans and recommend their 9B fan for the Anglia, at a cost of £69.80 + VAT. The unit is ex-stock and they accept credit cards. Could you ask for more?

l've come across several Anglias in service, running with just the fan blades removed and no additional cooling added. However; I'd probably have to agree with Graham and Warwick that filling a Kenlowe fan is a good idea for added peace of mind. There always seems to be an unexpected traffic jam around the corner in this country The Kenlowe conversion doesn't appear to be that expensive either so thanks to Graham for surfing the internet to find that out Ed.