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Will a paper air filter prevent hydrolock?

Recently, I got a bit of cork in a bottle of wine and decided to filter it out via use of a new paper-element air filter I had lying around.

Lo and behold, it prevented flow! So I got curious and tried several fluids. Freely permeable to gasoline and acetone, not so to water, beer, or wine (didn’t think to try hard liquor).

So, do it follow that an air filter will cause the engine to quit prior to destruction from attempting to “squeeze” water? (As for the other substances, if one is attempting to operate a vehicle through a waist-deep puddle of acetone, one has bigger problems than mere hydrolock;-)

The filter kind of acts like sponge. Once it gets saturated, it will start flowing water through.

So when you drive into the lake, the engine will die from air starvation like you described, but if it’s actually submerged, the water will seep through the filter and get into the intake and then into the cylinders. If you’re just doing a slightly too-deep ford and you just get a little splash in there, the paper filter can indeed save your butt-- yet another reason to avoid wire mesh type air filters!

Sounds like it’ll slow it down, but remember it’ll have close to 14 psi pulling it through the filter while the engine’s still running, so it could still pull it in.

Only if you’ve got your foot to the floor when you drive into the lake.

I thought about that, but won’t the water blocking the air filter let the engine pump out the air, creating quite a vacuum? Don’t think you’ll need the gas floored.

I think the pressures of suction from the motor will overcome the “paper” and will blow out the seals for the air cleaner and allow water to be sucked in to the engine. A paper filter isn’t stong enough to prevent hydrolock.

Perhaps you could design a special filter and airbox strong enough not to collaspe with the suction, but the standard factory supplied filters and airboxes will not stop the water if you wish to drive in to a river or lake.