I hydrolocked a Chrysler 440 Marine Engine twice in one summer in 2009. I pulled out the spark plugs and cranked out the water. It started and has run fine since then. 13 years later during a rebuild I found a cracked piston and some bent push rods. But in all those years (and 800 more hours) there were no symptoms: No noises, and good compression in all cylinders.

Great video and explanation. Thanks. I would like to reduce noise and exhaust gases and adding a turndown to have exhaust about 6" under water. I'm adding another elbow and finally having the rubber flapper facing like they were about the water. Technically should work but rather than learning the hard way looking for feedback. Thanks

Thank you for the information sir. Blessings to you

If you ever do experience this, also remember to check your oil BEFORE you attempt to start the engine. Water can also get into the crankcase and your oil will be a milky color. Do NOT attempt to run it like this. To fix it, multiple oil changes while running for approximately 1 minute in between changes until the oil is clean again. Then one more oil and filter change and you are good to go. I've seen this happen on bigger boats to the generator, when the vessel is run without the generator running and the sea-chest is left open.

@WayneTheBoatGuy

2 жыл бұрын

Great point!

Thank you for mentioning about hydrolock. Now I have a better idea of what it is. Can also learn how to avoid not having it happen.

@WayneTheBoatGuy

2 жыл бұрын

You're welcome!

Just got word from my mechanic that I hydro locked my I/O engine. Lucky me no real damage. This video explained it concisely. I feel better about leaving the dock again.

@WayneTheBoatGuy

2 жыл бұрын

That's good to hear that there was no real damage! Do you mind if I share your comment on my social media?

Never thought about ingress when loading into water. Makes sense.

@WayneTheBoatGuy

2 жыл бұрын

I’m right there with you!!

This happened to a mercruiser 190 that had a chronic dieseling problem. The dieseling was part of every time we went out. After years this occurred in the usual way. But, when I went to restart the engine it broke a part in the starter to protect the engine from greater harm. A rebuild of the starter took care of the break but we never solved the dieseling; dealers, favorite mechanics, etc. The mechanic did get the water out of the engine, of course.

This "Hydrolock" apparently happened to me this past weekend. I'm not sure why mine overheated in the first place as I had just put a new impeller in, BUT, I think I may have over lubed the new impeller and it could not create a suction. I don't know. Either way, it over heated and died while in motion. I'm now thinking that water shot up into the exhaust manifold and down into a cylinder or two. I changed back to the dryer impeller that was really working just fine and tried to start it. It has that locked "CLICK" sound and would not turn over at all. Didn't turn over the next day either after a full cool down. I did pull all the plugs and the motor turned over with no issues and sounded good. No obvious sounding mechanical issues. WHEW! The first plug I pulled did have water dripping out of the cylinder hole as I pulled it. I thought, "Man! The Hydrolock theory is working!". None of the other 7 plugs I pulled showed much sign of wetness. Maybe a little, but nothing dripped out like the first plug. I sprayed WD-40 in all the plug holes to help to alleviate any potential rust buildup and maybe eliminate any moisture. When I pulled the oil dipstick and looked at it, it looked fine. I'm going to put NEW plugs in it and CHANGE the oil before I try to fire it up. Wish me luck! I can't thank you enough for the video. I was SURE I had seized the motor.

@WayneTheBoatGuy

Ай бұрын

Yes - good luck!!! It sounds like you’re on a good path.

This guy is awesome

I apparently I hydrolocked a 300r just 10 hours in when I got in shallow water. I did not run it for more than 20 seconds and the block temp never got about 142. It’s ceased, but I feel certain it’s not warped. All plugs were clean

@WayneTheBoatGuy

Ай бұрын

Hoping all is well with yours!

Good stuff

@WayneTheBoatGuy

2 жыл бұрын

Thanks!!

I’m so frustrated!!! My flapper is new, both exhaust manifolds are new (they cracked) the marine mechanic can’t figure out why it keeps hydro locking!!! We never launch fast or slow down suddenly or shut off boat while under way. What are they not seeing?? We have a 2003 Maxum 2700 SCR. Any other suggestions we can explore why this keeps happening? 3x this summer!!!

I recently got a 25 foot Apollo and the first time out the engine started getting hot so I had to shut it down so as not to harm engine, but because of the heat the thermostat opened up( this was the ultimate cause of overheating) the hot engine percolated water into 3 cylinders and hydraulic locking happened. It took a while to figure it out..

How can I free the motor up after hydrolock? It spins by hand but not as easy as I think it should...any type of lube I can spray in the cylinders?

I have a 60hp mercury 4 stroke and engine was running fine and at top speed engine suddenly made a noise and died. Engine is totally locked up. Repair shop says it is hydro locked.says lots of rust in the cylinders and needs totally rebuilt. Anyway I can save it without rebuilding?

Merci beaucoup ❤❤❤❤❤❤

So what should be the next step after pulling the spark plugs and there is no water coming out?

This can also occur due to a bad manifold and riser or the gaskets between them. Also a bad head gasket will allow water to pass into the engine block. Remember, manifolds and risers are a 5-7 year maintenance item on I/O boats. It’s a do it yourselves maintenance item if you’re handy. Parts are expensive though. You should know how old yours are and if you don’t then play it safe and replace both sides at the same time.

After trolling today on Lake Michigan went to start the boat and tried to turn it over and immediately realized I was hydrolocked. Apparently fighting salmon on the transom and the previous owner taking out the shutters screwed me. Luckily engine never actually ran hydrolocked and pulled the spark plugs back at the dock and blasted the water out. Waiting on new exhaust shutters

@WayneTheBoatGuy

Жыл бұрын

Dang. So many people remove or ignore those.

My boat engine ran backwards for a hole summer lucky no damage

@WayneTheBoatGuy

9 ай бұрын

dang!

Could this also be a reason for slow turnover of an engine after launching the boat in the water? But starts just fine out of the water for flushing

@WayneTheBoatGuy

2 жыл бұрын

That's interesting. I wonder if it could be a weak-compression issue or somewhat blocked manifolds or exhaust. My thought is it's not strong enough to push exhaust through - but it's just a thought. You should definitely look into this further!

@pbtrilogy

2 жыл бұрын

@@WayneTheBoatGuy I think next time I launch I'll start the engine when the intake is in the water but before the exhaust like you suggested in the video, and see if it starts easier.

@Blakeneal407

2 жыл бұрын

@@pbtrilogy Happened with our old I/O mercruiser would start way faster out of water the reason is our mechanic told us is that there is way more back pressure and harder for the engine to start due to increased pressure in exhaust system a good amount of air (exhaust) to overpower pressure of water

Happened on my mercruiser 4.3 twice in two seasons. Think I have it figured out now

@WayneTheBoatGuy

2 жыл бұрын

Dang.

@Balmainbobby

Ай бұрын

What did you do to figure it out?

@sqlb3rn

Ай бұрын

@@Balmainbobby let it idle for a minute or two before turning it off. Both times it hydrolocked was when I shut it off when the engine was hot immediately after cruising or wakeboarding.wake boarding. The hot cylinders caused a few extra compression strokes in reverse and sucked water into the engine.

We just got this 4.3 last week and had an guess that it was going to be a head gasket Well it wasn’t it’s the intake manifold the hydro lock if it gets bad enough it will blow oil everywhere One way we checked if it was hydro locked was by the dipstick so be sure what you looking at

This can happen when winterizing as well. Be careful not to syphon water into your engine.

Hydrolock was the demise of my first boat. It was a sad day :( . It was an old used boat and unfortunately not taken care of very well by the previous owner. I also had a hairline crack in the block. How the two are related or if one caused the other, I don't know. I needed a brand new engine that was way more expensive than the boat was worth. After that I told myself that I will never buy another toy used.

@WayneTheBoatGuy

2 жыл бұрын

Dang. That’s awful. Thanks for sharing.

I can’t find a video on how to fix it

@WayneTheBoatGuy

Жыл бұрын

If your engine is hydrolocked, the 'fix' usually starts with removing the spark plugs to get the water out of the cylinders, an oil change and then checking for any damage that could have happened from trying to start it.

Related to "launching too fast" would be "forgot to pull the transom straps and launching" 😁

@WayneTheBoatGuy

Жыл бұрын

I've only forgotten those straps more times than I care to admit!

@peterjensen6844

Жыл бұрын

@@WayneTheBoatGuy straps. Drain plug. Trim down. Soooo much to remember! 😁

Tell us what to do when your youtube hydro locks 😮

I thought this was only an issue with Honda Valkyries!!

@WayneTheBoatGuy

2 жыл бұрын

This is that "other" kind of water intrusion! River water instead of coolant water.

Damn....this is what happened to my Donzi Sweet 16 this summer...120 hours and flawless every year and now it's junk. Motor is toast so if anyone needs a boat piece if fiberglass let me know.

@WayneTheBoatGuy

2 жыл бұрын

Dang - that really stinks!

So you know knowing about it, but you just researched it to tell us all your info, lol. Dude leave these video's to the professionals, if you don't know what you're talking about, please.

@WayneTheBoatGuy

Жыл бұрын

Nope. I’m going to keep on making videos SHARING WHAT I LEARN because there seems to be a lack of this information being shared by “the professionals” - whatever that actually means.