Driving Experience 15-Six

(including video)

ritje traction 4026


General impression
Traction ritje 1961Assuming the car is in normal running condition, one will be surprised to find that a Traction Avant handles exceptionally well in modern traffic. Surely, the engines are not as powerful as we are used to nowadays. But if we keep the cruising speed at the level the car was originally designed for, we can be assured of a fine and reasonably comfortable ride. For 4-cyl Tractions, the best speed for cruising is between 80 and 90 km/h (50-57 mph). 15-Sixes cruise comfortably at 90-110 km/h. On the Six, one will be surprised at the torque of the engine and the easy pick-up, even at speeds of over 90 km/h. Another benefit of the flexibility of the Six engine is the absence of a need to downshift very often. Once in top (3rd) gear, we can allow the speed to drop to 30 km/h and then accelerate again without the engine protesting.
Traction Rjidend Teller 20013
Tractions are known to be a bit heavy on the steering wheel (of course there is no power steering). This applies mainly at very low speeds; once the car is moving, steering the car through curves becomes easy. Small roundabouts and sharp bends require a bit of muscle. Tip to make steering a bit lighter: keep the pressure of your tires at about 2,0 bar. Modern tires will have no problem with a slightly higher pressure. Wear on the tires is even as always. 
Brakes are generally sufficient, although we should bear in mind that they are not power-assisted, and that they consist of drums only. Front brakes on the 15-Six are stronger and of a design identical to the front brakes of the HY Van. Applying the brakes too often on a downhill journey will cause their effectiveness to fade away notably. It is better to hit the brakes real hard and reduce speed drastically, allowing the car to regain speed gradually whilst at the same time giving the brakes the opportunity to cool down a bit, rather than keeping the foot on the brake all the time.
Traction Rjidend Teller 10999Gearbox
The three-speed transmission with synchromesh on 2nd and 3rd is something to get used to. To begin with, changing gears should be done slowly, allowing the synchromesh to do its work. If one is too impatient, teeth grinding will be the result. In flatlands like Holland one will not have too many problems. In mountainous areas one is often limited to 2nd gear only. Unless of course the road becomes so steep that 1st gear needs to be selected. The fact that the car will have to come to a complete standstill before 1st gear can be engaged, can be a real pain in the neck.

I have driven my 15-Six on roads -mainly in the UK- where the gradient was as much as 20-25%. Uphill there was no problem at all, but going downhill at snail's pace with the engine roaring and even then having to apply the brakes from time to time, is quite scary, especially when there are lorries and other vehicles breathing down one's neck who seem to want to go faster than you can possibly go at that moment.

Starting te engine
Cold start
Starting the engine can be quite an experience, especially when it is hot. On the 4-cylinder Tractions the engine is best started with the clutch pedal depressed, whereas the 15-Six engine should always be started with the clutch pedal released (different design of the clutch pressure bearings). When the engine is cold and the car has not been used for a while, it is wise to prime the fuel pump with the manual lever until you are sure the float chamber of the carburetor is completely filled with fuel. Retard the ignition a bit turning the knob on the dashboard counter-clockwise, fully pull the choke (S for "Starter" in French) without touching the accelerator. Turn the ignition on, pull the starter knob (D for "Demarreur" in French) and the engine should start promptly, in less than two full revolutions of the crankshaft. As soon as the engine fires, push back the choke as far as possible, allowing the engine to run evenly without stalling. Also advance the ignition to ensure a smoothly running engine. This is a matter of feeling, but it is fun to feel a bit like a stoker on an old steam engine. It is best to put the engine to work as soon as possible, which will allow it to heat up faster. Warming up the engine with the car standing still causes unnecessary wear. Engage 1st gear and get moving  without roaring off (fully push back the choke knob at your earliest convenience). Shift to 2nd and 3rd gears as early as possible and allow the engine to get ready for the real work at moderate rpm. After a couple of miles you will notice that the engine starts to respond better to the accelerator. Now it is ready for the job. Don't be mistaken how long it takes before the entire engine block and all the moving parts inside will have reached their regular working temperature. This means that the temperature of the engine oil in the sump should be at least 60 degrees C. On my 15-Sixes (with 7-8 liters of oil in the sump!) it takes at least 15 km of steady driving before the (extra) oil temperature gauges I have on both cars, will start to move upwards. Under normal (steady) driving conditions the engine oil should reach about 80-85 degrees C. The temperature will drop if the engine has less work to do, for instance while motoring along small country roads.
Hot start
Starting the (very) hot engine of a Traction Avant is a different story. If you turn the engine off after a trip of some length, the temperature of the coolant is likely to rise to 90 or even 100 degrees C. This is caused by the fact that the coolant no longer circulates through the system. What can happen as well, is that the carburetor will start to overflow, with fuel leaking out of the thin tube on the intake manifold. This is caused by the intense heat radiation of the exhaust manifold that sits immediately below the intake and the carburetor. The fuel will start to boil and expand. If you try to restart the engine under these circumstances, it is likely that it will be flooded and will fail to start. There are two possible remedies: one is to wait for the engine to cool down (will take quite some time), the other is to gently fully push down the accelerator and keep it there without moving it until the engine has fired. Retard the ignition significantly and crank the engine until it fires. Don't be afraid to operate the starter for 15 seconds or more. This is the only way to flush out the excess fuel by allowing the engine to suck in as much fresh air as possible. People who are afraid of running the starter motor for more than a few seconds will find that it takes several attempts to get the engine going. Releasing and moving the accelerator up and down will increase the engine flooding and will prevent it from starting.
Traction Twisk 20020Starting Trouble
The design of the Traction starter motor in combination with the 6 volt electrics is likely to cause the starter pinion to disengage from the gear rather easily. This leaves the starter motor roaring on without doing anything. If this happens, release the starter knob, make sure to retard the ignition a bit and wait for the starter motor to come to a complete halt before trying again. Only patience will help you out of this problem; eventually the engine will start. This again is one of the charms of driving a Traction Avant!
Vapour Lock
There are two conditions that will cause the engine to stop or not to start at all. One is the dreaded "vapour lock", the other is icing on the carburetor jets.  Vapour lock may occur when the engine is very hot. It is caused by boiling and vapourising fuel inside the fuel line between the pump and the carburetor. Pockets (bubbles) of vapourised fuel may develop as a result of intense heat radiation. They can block the flow of fuel into the carburetor, causing the engine to stall. It can happen while driving (usually at the most impossible spot one can think of, like a busy road crossing) or while the engine is standing still. One will have to wait for the situation to cool down sufficiently for the flow of fuel to be restored.

The development of vapour lock can be prevented by ensuring that the fuel line to the carburetor is kept as far away as possible from intense heat sources like the exhaust manifold or the top of the radiator. Also, the use of rubber (neoprene) rather than copper fuel lines in the heat zones will help reduce the possibility of vapour lock. The other thing to ensure is that the fuel pump is working flawlessly. The higher the pressure of the fuel in the line between the pump and the carburetor, the more chance there is that the flow will not be interrupted.

Icing on the idling jets of the carburetor is possible at outside temperatures between 4 and about 10 degrees C. Humid air will enhance the problem. It may occur rather shortly after the cold engine has been started, causing it to stall. After a few moments the ice will have melted again and the problem will be gone. A remedy to ensure the engine will not stall at every street corner during the first few miles is to pull the choke a bit. The icing will disappear as soon as the engine develops enough heat of itself to warm the carburetor via the so-called "hot spot". One should not attempt to solve the problem by adjusting the idling mixture. This will only result in an engine idling at too rich a mixture once it has heated up. In summer time, with low relative humidity and higher temperatures, icing will not occur.
Electricity Management
The 6 volt electric system with its weak DC dynamo is the reason why we have to pay extra attention to the consumption of electricity while the Traction Avant is operated. On a bright sunny day there is never a  problem.  Turning signals and brake lights usually cause no trouble because they are used for short periods only. It is when we turn on the headlights that we should be aware of the fact that the output of the dynamo will barely be sufficient to feed the lights -that is while the car is moving at normal speeds. Under these conditions the battery is not charged, so it better be well charged when we set off. In city driving with the headlights on the output of the dynamo will be zero when we are standing still with the engine idling. This means that the lights will draw on the battery. If we keep on doing this for a while, the battery will discharge notably. It is wise to switch the lights back to "small"  (V) while waiting at a traffic light. This will significantly reduce the drain of the battery. If we have made a nocturnal trip and know that significantly more electricity has been used than generated, it may be wise to hook up the external charger once the car is back in the garage. A good alternative is to ensure the next trip is made in daylight, allowing the battery to be fully charged again. The amperemeter is likely to indicate a significant charge (C) for a wile, which indicates that the battery was in need of it. As soon as the needle of the amperemeter starts to move back towards "0" (always on the C-side), this is a sign the battery charge is improving again.
Low Energy Lights
In some European countries cars are required to have their (low beam) headlights or something similar on for better visibility, even during daytime. With the original DC dynamo on he car, this will mean that the battery is not charged at all. Frequent use of the external charger will be necessary to ensure that the battery does drain over time. There are two ways around this problem: one is to fit an alternator instead of the DC dynamo. Parts suppliers like CTA offer alternators that have been adapted for use with a 6 volt system. These are easy to install on a 4-cyl Traction and will provide more energy -their capacity at 6v being about twice that of the DC dynamo. The other way is to install some modern energy saving lighting on the car. The use of LED's for the tail and brake lights will serve two purposes: better visibility and a low energy consumption. There is an article about LED's on this website. On my black 15-Six I have installed two small high-power halogen lights (only 2W each) that belong on a bicycle. The amount of light they produce is sufficient to make the car well visible during day time. I use these lights quite a lot when driving on country roads, even though there is no rule that requires me to do so in our country.
Please start the video and join me for a short ride.