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Budd Stanley photos
Curing Hydrolock
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Budd Stanley photos
Curing Hydrolock
Know where your engine grabs fresh air, so you can better manage water crossings,
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Budd Stanley photos
Curing Hydrolock
If you get enough water into the combustion chamber, nightmares like this can happen.
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Budd Stanley photos
Curing Hydrolock
Dry out the entire intake system, and peer in through the throttle body to see how much water made it into the manifold.
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Budd Stanley photos
Curing Hydrolock
Tricky part is to ensure the distributor is dry; having air on the trail really helps here.
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Budd Stanley photos
Curing Hydrolock
With all the spark plugs removed, run the pistons on the starter until you can’t see water spraying out anymore. And it will spray; so protect everything you just dried.
Story & photos by Budd Stanley
CPR for your 4WD’s drowning engine
Hydrolocking. If this is a word you don’t recognize, you should learn it fast in the world of wheeling. For those who have not yet had the very unpleasant experience of meeting this engine issue, hydrolocking is a very big frown that usually comes just after smiles and giggles.
Fording creeks or streams is one of the highlights on a good wheeling trip. Like little kids jumping into puddles, we love flinging our 4WD’s into a water crossing with reckless abandon, in an effort to create the biggest splash and the loudest cheers from the spectators. However, splashing great amounts of water up into your engine bay is a recipe for disaster, trust me, I’ve flooded an engine or two with H2O instead of fuel.
For the uninitiated, hydrolocking is the introduction of water (or other fluid substances) into your engines combustion chamber, most commonly getting in through the air intake system. This becomes detrimental, as the physical properties of water do not mix well with the compressing actions of the engine. A gaseous mixture of air and fuel mist is capable of compressing when the valves close and the piston rises up on its compression or ignition stroke. Water on the other hand does not compress, so if you have enough water trapped in the combustion chamber when the piston comes up, your engine will give way before the water will.
If you read our last issue, we gave you the pros and cons of installing a snorkel on your intake system, an ideal way to keep the muddy waters at bay. However, if you do get water into your intake and manage not to bend a rod or blow your engine’s head gasket, this is what is required to get back up and running once again:
- First things first, turn the engine off if the water hasn’t already done that for you!
- If you are not on dry land, tow/winch the vehicle onto a suitable dry area to work.
- Disconnect all intake piping leading up to the throttle body or carburetor and dry the entire length with paper towel. Yes, this is long and tedious… and really sucks for those with turbo engines, but essential to not blowing up an engine (those with turbos, don’t forget the intercooler, it may need to be pulled and drained).
- Place the wet air filter in the sun to dry or over a heater vent in another vehicle.
- Disconnect the distributor and spark wires. If you have compressed air on board, blow out the distributor, distributor cap and each end of all the lead wires and clean up with a paper towel. Don’t forget the coil pack(s) as well.
- With the spark leads off, blow out the spark plug channels with compressed air if that is available, or twist up dry paper towel and slip it down next to the spark plugs to soak up any moisture. Do not remove spark plugs until all moisture is gone.
- Once everything is clean and dry, pull the spark plugs and let them dry in the sun/on a heater vent.
- At this point, all ignition and air intake equipment should be dry; the only thing now is to remove moisture from inside the intake manifold and combustion chamber. With the spark plugs all removed, crank the starter to get the pistons pumping. With the open spark plug holes, there will be little compression to do any damage and any moisture should be ejected out the spark plug hole (glow plug holes in a diesel). This could take some time and can drain a battery.
- If you are on your own and can’t afford a dead battery, put the vehicle in gear and 4WD, jack up a front wheel and spin by hand to turn over the engine manually.
- Once you are sure that the combustion chambers are clear, put everything back together and attempt to start the engine.
- Don’t forget to inspect the radiator, which can clog with debris following a water crossing. Wash out as best you can, because it would really suck to overheat after getting away with hydrolocking your engine.