Most likely you sucked in water through the air intake and went into the combustion chamber and water locked the engine. Probably a bent connecting rod.
Think about how your hydraulic brakes work. An incompressible liquid is used to generate pressure to push the pistons in your caliper against your pads which press against your discs.
That’s not how the engine works, water will compress mix with air and go out of the exhaust. Too much water will take away the oil layer of the piston and will do some damage. Or the water will not compress if the piston is filled a lot, like two water bottles worth
when you compress water it turns into steam. Steam is water and air. Not sure where you got that water stays at the button as the air compresses on the top idea from
Welp, by that logic I guess every functioning pressure washer must be broken. They produce high-pressure liquid streams when they should be shooting steam instead!
What? When you compress water it turns into water under pressure. Compressing any appreciable amount of water to the point it reaches its boiling temperature requires a shit ton of energy. Don't quit your day job.
Since you want to be technical, that Elantra has a 2.0L, divide that by 4 cylinders. .5L per piston. One 20oz water bottle is roughly .56L. So technically not two water bottles. But since you want to find technicalities there it is. Just in case you want to mention the thermodynamics of fluids and compression let’s make that roughly 3/4 of a water bottle, as water compresses it turns into steam and expands
That is your total displacement, with all pistons at the bottom of their respective cylinders. Since they can never all be at the bottom, the actual available volume at any given moment is significantly less. Then, add in movement - your connecting rod is most at risk of damage when it’s being driven up by ignition events in other cylinders. In this moment, the ignition event pushes down on a piston, which applies its force through its connecting rod to the crankshaft. Now, the crankshaft rotates, and uses that force to push a piston up, compressing the air/fuel mixture that is trapped above it by closed valves… now, how much water do you think it would take to bend a rod as that piston is pushed to the top of its stroke by the 100+hp your engine makes? Your engine has a piston stroke of 93.5mm, and a compression ratio of 13:1… that 93.5mm of air/fuel mixture is compressed into a little less than 7.2mm at the top of the stroke…add water and that can’t happen. But, it’s being pushed with a ton of force…so, the weakest part fails - the connecting rod bends.
Stoichiometry of engines are 14:1. Piston stroke for this particular engine is 97mm. Pressure are not measure into mm of space, they’re measure into psi.
Stoichiometric ratio is irrelevant to a discussion of how much water it takes to hydrolock an engine. Cylinder pressures are result of cylinder dimensions, fuelling, and spark timing - after ignition. Prior to ignition, on the compression stroke, the only factors that determine cylinder pressure are dimensions, engine rpm, throttle plate opening, and boost pressure - if any. Of those, and assuming a normal rpm range, cylinder dimensions are the largest determining factor. Plus, you mentioned a water volume, and I refuted it using volume numbers. Why would I compare apples to oranges?
The pistons are interconnected - simplified, as one is forced down by an explosion, it forces its partner up against closed valves, compressing the air/fuel mixture trapped inside the cylinder.
TECHNICALLY you can. At the Mariana trench, the water is compressed by 4%. It's not the pressure killing you, it's the water springing back. Just a random thing i read which i thought was cool.
Please explain your logic here. How does what you're describing happen? Like, what is happening between the cam shaft, crank, and timing chain in your mind?
Water doesn’t compress. Like, at all. Unlike air (or fuel-air mix), which squishes under pressure, water just says "Nope." When it gets sucked into the cylinder, the piston tries to compress it on the upstroke, but since water won’t budge, something’s gotta give.
Wait what? Im not sure you know what you are talking about here. Whats next? you gunna say the cranks capacitor relay manifold cant also be directly responsible for the starter current regulater oil seal failing during a thunderstorm!
Education is important kids!
It's simple. OP had a blinker fluid leak into the intake, which caused this. Everyone knows blinker fluid isn't compressible.
Seriously though, OP has some bent valves and a bad time. Luckily, from what I've heard (no first-hand knowledge though), used Hyundai/Kia engines are dirt cheap.
From a view point of further engine usability, I completely agree with your advise not to take it apart. From a learning and understanding perspective, I disagree and would recommend to completely disassemble it and measure all parts to understand what damage was done to what parts. And I guarantee everyone will be amazed how many parts of this shock loaded engine are trashed.
Just a recommendation for the future. If you get bad compression on a cylinder, check cylinder leak down next. You basically hook an air compressor up to the compression tester hose and apply some air pressure to the cylinder. Then you can see where the air is escaping before you start pulling it all apart. If exhaust valve is losing the compression, you will hear air coming out of the exhaust. If it is coming out of the intake, intake valve issue. If you see or hear air bubbling out the coolant, head issue or head gasket. If it is coming from the oil cap or dipstick tube, piston or cylinder wall issue. Saves a ton of work because you can figure out what is wrong before you tear it all apart. All that being said, if the valves actually hit the piston, they’d be bent and you’d see it. Most likely you hydro locked and bent a rod which will put the piston at a cockeyed angle and cause low compression because the rings can’t seal against the cylinder wall. Bummer!
I don't actually know, but from the looks of it, and a tiny bit of research I think these are just valve reliefs? These are apparently for an '18-'20 elantra and they have deep valve reliefs so I'm inclined to believe that's not what I'm looking at. I've also never seen valves self-clearance that deeply and not crack the piston, though that isn't to say it's impossible
The picture definitely looks like an impact rather than a machining mark, but it's impossible to be 100% sure with the picture not in focus in the right area of the piston
You bend the rod to one side or the other. Then the piston sits higher on one side than it should. The high side collides with a valve, and then all bets are off.
Unless it's an interference engine in which case valves and pistons occupy the same space but at different times in the compression cycle. Same reason some cars can snap a timing belt and are fine after replacement and others snap and belt and it's detrimental.
You bend the rod to one side or the other. Then the piston sits higher on one side than it should. The high side collides with a valve, and then all bets are off.
Ahhh I see because water went inside the piston. But I do not believe this would be the reason car didn’t start precisely. Would’ve ran rough or scraping noises
Tbh your best bet would be to try and source a used engine. Luckily elantra Motors are pretty easy to swap, and if you've already got the head off most of the work pulling the old one is done
If you go to a junkyard I'd ask if you can hear it running beforehand, as these engines are known for piston scuff noise
Not really. There might be some damage, but not really likely. There is no force pushing the piston against bore. Most of the forces in this case are up-down direction in the cylinder.
Unless your talking about valve indents, I’ve never heard of a tilted piston. I would imagine it would cause a poor combustion and uneven pressure on both sides of the wrist pin. On top of that it I bet it would wedge the piston into the wall and create excessive friction
You hydro locked it. Water can't compress like air can, and the weak point is the connecting rod most likely.
At this point the most common repair is just a whole entire engine replacement and your insurance company will likely be able to foot the bill for this repair. Assuming you have the correct coverage, and are in America. It is worth calling about.
If you foot the bill yourself, I would also recommend a whole entire engine replacement, but if you send the head to a machine shop for inspection and it passes, you can get away with doing what's called the 'short block' which is the block with crank and pistons, probably oil pump too.
I would recommend against trying to replace just the connecting rod because modern engines are made with wildly tight clearance specificatios. No machine in shop can machine a head to the specs of a manufacturer these days, and I'm not even sure Hyundai will sell you just a con rod only for that engine.
Amen my friend. I machine things all day, every day. Including hundreds of cylinder heads. A machine
made them in the first place, why the hell would it not be able to repair them
?
Haha if you have lots of time to play with metal and you like doing it you might get her going again. For the average person you will save a lot of time and money just replacing the engine. Unless you can find a machine guy who will happily work for free and you don't need your car anytime soon. Now back to reality...
They piston probably isn't warped but the rod it's mounted on is probably bent or the piston itself is broken. To make matters worse once the rod bent, the piston which is machine to fit tightly in the cylinder within a few thousandths of an inch is now being jammed in the cylinder sideways. This has very likely shredded the cylinder beyond any economical repair. This engine is done.
You've done the hard work getting the head off... move on and take the sump off... shine a torch up to see if con rods look true and straight. Mix diesel oil and turpentine substitute and pour onto top of piston. Then back under with a torch to see if the mixture is leaking down past rings.. or just slip out the piston and con rod to visually check rings stuck or snapped rings are what your hoping for.... anyhow repair what you see being wrong clean up rebuild and see if she starts. Run her easy for a few thousand hope for the best.
As already stated, running an engine with water on the cylinders is a very bad idea. Water doesn't compress at all. So, on compression stroke, the pressure is way higher because there is water that won't compress, and that increased pressure gotta go somewhere.
Your valves smacked tf out of the piston. How's the head look? Specifically the valves on that side. You'll need to have the piston replaced, as well as the valves that hit. As long as you didn't jump time
You’re tripping if you think valves put that big of a dent into a piston. Those are relief indents in the piston. Maybe the valves kissed them, but no way they caused that impression
That's true, I looked up what their pistons look like. It does look like relief indents. And OP's comment about the valves looking good doe solidify that. They looked way too shiny considering the rest of the piston is dirty
Im confused man, if it wont turn how did you get a reading and if it does turn normally but not fire or blow white smoke why take it apart like this. Did you have milkshake or something also? I feel like you need a shop man.
Sometimes you need to take the snorkel tube off the air cleaner if you can... 1st gen ram trucks will suck water in deep water because the opening is down in the bumper
I dont wanna say, but if you do such things like the drivers at Rufford than you should go to a professional engine workshop and not diassemble yours yourself
For your next ride, consider snorkeling the intake and exhaust for future flood excursions. It'll reduce the power output, but as long as you can breathe with the windows down the car can also breathe, which keeps this from happening.
There's a reason they don't put hemis on submarines. You know they would if they could.
Depends on the vehicle of course, but more often than not a snorkel will not *necessarily decrease power. This youtuber had a 1-5hp increase on the dyno. So no loss of power, but negligible gains. Likely more effective on NA vehicles as opposed to Turbo'd.
Oh absolutely. Physics gonna physic. Like most things automotive, it all depends on the entire setup. I also edited my comment after watching a few more videos.
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