Cooling - CITROËN Amicale 5 HP Manual

.14- COOLING

The 5 HP are cooled by thermosiphon. The principle is simple: the specific weight of hot water is lower than that
of cold water; as a result hot water rises in the engine, where it is replaced by cold water coming from the
radiator. But the cooling effect is weak and it implies having a full circuit, the good circulation being around 90
°.
14 a - How to improve it?
- By adding a current car electric fan fixed behind the radiator, as high as possible, it accelerates the lowering
of the temperature in the radiator There are very high-performance fans , and if your electrical equipment is 6
volts, it can easily run a 12-volt fan.
- For perfectionists: use a current electric car water circulation pump (eg: Bosch pump from Mercedes reference
A: 001 835 13 64). Two installations are possible:
-
A / Bypassing the original installation, the water is sucked in by a bypass at the radiator outlet and pumped
back into the engine pipe
B / More technical: weld a second water outlet, in the lower water box of the radiator of the desired diameter to
connect the water pump which can be hidden in the frame member.
The discharge will be at the location of a grit removal tablet located on the side or on the rear face of the
engine. It suffices to replace the pellet with a small water pipe which will be machined and which will be
screwed into the block at the location of the pellet.
In both cases this pump can be controlled manually or be automatic if it is connected to an electrical probe
(connected continuously your motor would not rise more than 60 ° which would adversely affect its
performance).
To precisely monitor the temperature of the water circuit, we recommend the water thermometer on the
instrument panel with a probe which is mounted on the upper cooling hose (cylinder head-radiator).
There remains the problem of coolant. Three options are possible:
1 / Tap water: but beware! With each full water it contributes to the scaling of the engine and the radiator,
which hardly need it.
2 / Demineralized water: it does not have this drawback, but requires, like tap water, the emptying or the
addition of an antifreeze in winter.
3 / The "Four seasons" liquid: it is far preferable, "Experience shows that an all-season coolant is less harmful
than the annual draining of the cooling circuit. Exposed to the air, the block rusts , and the grit blasting tablets
corrode faster, while the radiator hoses tend to dry out and lose their seal on the fittings.
However, if the radiator is disassembled, it is difficult to recover the mixture cleanly. cooling if the bottom of the
water box is provided with only a single screw instead of a drain valve. Watering of the feet and all the rest
guaranteed ... "
When it comes to a good liquid (oil companies or large automobile manufacturers), it also has two advantages
because it contains anti-corrosion additives, which are undoubtedly beneficial for the engine and for the
radiator. And by virtue of its composition, it makes it possible to significantly raise the boiling temperature,
which on an engine having only too much tendency to heat up, is not negligible.
Periodically check the quality of the coolant:
Set the digital multimeter in volts DC to 20 volts or less. When the engine reaches operating temperature,
insert the positive probe directly into the coolant. Place the negative probe on the negative terminal of the
battery.
If the digital meter reads 0.4 volts or less, the coolant is OK.
Otherwise the electrolysis additives are exhausted ...
Choose an IAT liquid (old solution based on ethylene glycol) and not OAT (new organic acid technology) which
can be very harmful for our old cars
Source: Forum: `` Cylinder head gasket ''
14 b - A good level
The cooling circuit normally contains around 8 litres (much less if the engine is scaled up...) The upper radiator
water box contains a good quarter of it alone. So check its level carefully at each stop and don't be surprised to
sometimes add a litre of water.
Some prefer to leave the water box half full ...
These losses are nothing to worry about; they are due to evaporation, to heating which increases the volume of
water but also to the loss through overflow at each turn or at each braking.
Check the condition of the hoses regularly and do not hesitate to change them if you see them starting to crack.
Doc: http://www.precimotor.com/refroidissement.html