This project will cover the preparation of my Foreman ATV for deep water crossing. This project will include the fabrication and installation of an engine air intake snorkel, and some other tips/tricks to to help in deep water crossing. This article is just my opinion and not gospel on this subject, so take my advise at your own discretion and ride at your own risk. Before riding deep water even on a non-modified bike, read your owners manual and find the air box, carburetor, drive belt housing drain locations, locate the spark plug (plugs if a twin cylinder) and learn how to remove them with tools stored on your bike - ALL BEFORE LEAVING YOUR HOUSE.

The Honda Foreman 450 has a factory intake snorkel that takes in air next to the gas tank at about the height of the word "Foreman" on the plastics. It works well for most people in stock form, but I wanted the assurance of a dry crossing for deeper water. After completing some research online in June 2005, I came up with a plan and was off to the plumbing store to pick up some 1.5" ABS pipe, fittings and glue.

 

I started by removing the gas tank cover and removing the factory snorkel. The next task was to mill down a short piece of ABS pipe to exactly match the diameter of the stock snorkel where it enters the air box. Once the new pipe fit snugly I coated the end with Silicone Gasket maker and installed it with the factory rubber seal and clamp. Next a series of 22.5 degree couplers were used to route the pipe around the engine then it was a straight shot to the left front fender area.

Another series of couplers routed the pipe through the wheel well staying clear of the tire, up through the fender and through the Front Rack.

Once the pipe came through the fender and the rack, I fabricated a mount from galvanized sheet metal to secure the snorkel to the front rack. I cut a hole the same diameter as the pipe in the middle of the tin, and sandwiched the metal between a straight coupler on the bottom and a female threaded coupler on the top. The plate was then attached to the rack and painted black.

The reason I used a threaded coupler on top of the mounting plate was so that I can screw in a short snorkel for everyday riding and a longer one for planned deep water crossings. Using a long snorkel all the time makes the system less sturdy on rough trails, and is directly in the view of the rider.

Both of my snorkels have a 90 degree fitting at the top to suppress rain, snow or splashing water from entering the intake.

There is no exact science to this process as every bike is different, it took some trial and error and a lot of dry fitting to get every thing routed just right. Parts were only glued once everything was dry fitted in place. Be sure to not run piping too close to the engine as heat may damage the pipe, be aware of tire clearance when routing pipe in the wheel well, and be aware of chafing and moving parts that may cause damage to the pipe over time.

The only change I made since the original installation was cutting the pipe inside the fender and adding a silicone coupler. After the original installation there was no way to remove the front plastics when working on the bike, the rubber coupler now allows me to disconnect the snorkel pipe with ease.

Other Tips:

For deep water crossings, there are some other things need to be addressed to keep the bike running when submerged. All vent lines which on the Foreman include front & rear differentials, front and rear drum brakes, gas tank, and carburetor all need to be extended to a higher location. Some people extend them to the height of the handlebars, or attach them the top of the intake snorkel, I chose to extend and run them inside the centre headlight pod. The over flow hose on the bottom of the carburetor should not be extended to a higher location as it needs to gravity drain if the carb overflows. (more on this later)

Next you will need to water proof all electrical connections, especially the ignition system or it may stall when submerged. An application of dielectric grease in the spark plug boot, and all electrical plugs (especially the ignition coil) should keep things dry and running.

When fording deep water, you will need to plug off (temporarily) the carburetor over flow tube.  I have found that the stock check valve will allow water to enter the bowl of the carb and stall the motor. A golf tee works well, and be sure to always remove the plug when you finish your ride. Leaving it plugged may cause problems while transporting or storing your bike. If the float sticks, fuel will not drain and instead will fill the cylinder and engine with gas possibly hydro locking it.

On the foreman, the crank case breather is attached directly to the bottom of the air box. The problem is that any more then about an inch of water in the air box, and you can get water directly into your engine oil. I removed the stock breather hose and installed a longer hose that leaves the air box, routes up over the carburetor intake boot, and back down to the engine. This creates an upside down trap that will not allow water to easily enter the engine.

I currently do not use an exhaust snorkel, as long as the engine stays running water shouldn’t enter through the exhaust. The trick is to keep blipping the throttle at all times as the engine could stall at idle when the exhaust is underwater. To alleviate this you can temporarily turn up your idle setting on the carb, or fabricate and install an exhaust snorkel.

What to do after sinking an ATV:
 

Since I’ve installed my Snorkel I’ve gotten the engine wet mostly from pushing the limits of my design and rider skill. One time the bike floated, I lost my balance and the bike tipped over.

• As soon as you pull the bike from the water DO NOT TRY TO START IT.

• First stand the bike up to drain the muffler, then drain the air box, and carburetor bowl (small screw bottom right side of carburetor).

• Be aware of the environmental implications of working on your ATV in the woods. Don't drain gas or engine oil onto the ground, use an empty pop bottle or other suitable container instead. 

• The air filter will most likely be wet and will have to be dried before starting the engine.

• Next remove the Spark Plug and turn the engine over to eject any water that may be on top of the piston.

• Next check the oil level, most times it will be over full (from water infiltration) and you could damage the motor even trying to start it. If your deep water riding you should always have spare equipment to do one or two oil changes in the woods, but a simple trick is to remove the oil drain bolt, water is heavier than oil and will run out first, when you see engine oil quickly reinstall the oil drain plug. It will not fix the problem but may get you home if you don’t have far to go.

• If you have a Honda automatic transmission I would not risk riding the bike at all unless there is absolutely no other option. These oil driven transmissions are expensive and don't like water.

• If you have a CVT belt driven transmission you will need to drain the belt drive box as well.

• Once you run the engine, the small amount of water remaining in the engine will turn the oil milky grey in minutes.

• If you have a CVT - Once the engine is running, put the gearbox in neutral and run the engine at moderate to high RPM to spin and dry the drive belt.

• Now it's up to you to decide to ride the bike home or tow, towing will guarantee that the engine is not damaged.

• If the bike is running poorly or stalls after a short time, re-drain the carburetor and check the gas tank vent hose, if it has water inside it wont allow the tank to vent. You can test this latter theory by unscrewing the gas cap and see if the stall problem is fixed.

Once you get home:

• If the bike was submerged in clear water you will need to complete multiple oil changes with cheap motorcycle rated engine oil. Drop the oil, refill, run the engine for 5-10 mins, then check to see if oil is turned milky, if yes repeat oil change. You may have to repeat this 5-10 times. Perform one final oil change with your normal ATV oil and install a new oil filter at that time.

• If the bike was submerged in muddy, dirty water my best recommendation is to remove the engine and split the engine cases for cleaning as muddy sediment will remain inside the motor and do serious damage to bearings inside over time.

• Next remove the seat and put it somewhere warm to drain and dry as the seat foam will be water logged.

• Check both differentials for water infiltration and drain/refill if needed.

• If your bike has a Hi-Low-Reverse gearbox with a CVT belt driven transmission then the gearbox oil will need to be changed.

• Remove the CVT cover for inspection and cleaning of the clutches - especially if submerged in muddy water.

Things to remember:

1. When the bike is submerged, large ATV tires will cause the bike float which will reduce traction and can make the bike very tippy so be careful and keep your balance.

2. Never cross an area that you are unsure about, and be aware of underwater currents that may drift a partially floating ATV into danger.

3. If your riding an ATV in deep water, your going to get very wet yourself. Beware that the water may be cold so dress accordingly and beware of hypothermia, its symptoms, and necessary first aid.

4. Before you leave home, become familiar with the location of all necessary drains, spark plugs and practice the steps above at home. Equip the bike with all tools you need to complete the work listed above in the woods. Inspect the carburetor drain screw and operate it to ensure it's not seized.

5. Be aware of the environmental implications of working on your ATV in the woods. Don't drain gas or engine oil onto the ground, use an empty pop bottle or other suitable container instead.

6. Have enough oil to perform at least one oil change in the woods if you sink the engine.

7. Sometimes during deep water riding (or heavy rain) the vent hose for the fuel tank may plug causing the bike to stall (similar to running out of fuel). To check open the gas cap to let air in if the stalling is fixed you found the problem. Next tighten the cap then remove the vent hose and blow through it to dislodge any debris. Do not put the hose in the hole near the handlebars if there is water at the bottom of that hole just leave it loose to one side or the other.

8. Deep water riding should be considered an extreme sport as it certainly is not the norm. Like all extreme riding, there are always additional risks so ride safe, have the right equipment, and never ride alone.
 

Cheers, MIKE