Water crossings are one of the more challenging aspects of off-roading.
When it comes to a water crossing you want to make sure you have all the necessary information on how to get through a water crossing successfully as well as any recovery gear. Being over prepared is better than having only half of what you need.
There are some things to keep in mind when going off somewhere you are likely to find a water crossing.
Water in the Diff Oil
It is extremely important to take your time and let the transmission and differentials cool down before crossing. The hot air inside the differentials expands and if you suddenly cool it the air will suddenly contract and pull in water past the oil seals.
Water can also enter the engine through the breathers. Have the breathers extended with vacuum tubing high up into the engine compartment to prevent water entering them.
It is best to avoid the temptation to change gears while going through the water crossing. You see a mechanical clutch depends on friction to function properly. When you depress the clutch pedal the clutch plate moves away from the flywheel allowing you to change gears. Upon releasing the clutch pedal the clutch plate returns to the flywheel and restoring the desired friction.
By changing gears in the water, you open the flywheel to get lubricated by the water and thus taking away the friction which is required for the clutch to perform correctly.
Air Intake and Wading Depth
You really do not want water entering the engine. A snorkel is the best way to help prevent water from getting into the engine.
The engine compartment is also in danger of flooding. This causes short circuits in the wiring and the vehicle may cut out right in the middle of the crossing.
A good way to help prevent the engine compartment from flooding is to make a cover to go over the front of the vehicle covering the grill. This will make a bow wave at the front of the vehicle pushing the water away. Helping to limit the water entering the engine compartment.
All 4×4 vehicles are designed to cross over water. The depth at which they can go is referred to the wading depth. All vehicles have their own wading depth. Some claim to have a wading depth of up to 800 mm but this usually refers to non-flowing water.
A good rule to stand by is that if the water looks too dangerous to walk through it is most likely too dangerous to drive through.
When the radiator comes into contact with water while running the fan begins to act more like a boat propeller. Only the blades bend due to the plastic material they are made from. Leading to a massive hole in your radiator. To prevent this, it is best to remove the drive belt.
If your vehicle has an alternator which has an integral vacuum pump you will not have brakes during the crossing.
Though not to worry about the water pump as you will be crossing into the water with a cool engine that the time spent crossing over won’t be enough for the engine to overheat.
Mark Your Obstacles
All sorts of things could be carried in to create obstacles on your path ahead. While everything is cooling test the area.
Test the flow of the river by walking into it and deciding if it is safe to cross through. While you are doing this check the depth of the water to ensure a safe crossing. You will also want to check the bottom of the river by using a tent pole of sorts to push into the bottom of the river to see how likely you are to get stuck.
Lastly using poles mark out the obstacles and the path you will take through the water crossing.