Appears to be hydrolocked

[CurrentObsession]

1999 5.7 liter with a BIII drive. Fresh water cooled.

Just got back from the boat launch, engine would not turn over. Ran fine on muffs yesterday, didn't turn off the water until about a minute after shutting the boat down. I know you can't run the hose on a jetski engine while it is not running, but didn't think it was an issue with an I/O??

 

[boat1010]

Re: Appears to be hydrolocked

I think you are jumping the gun a little.. You can run the muffs on it all day without it running. Makes no difference. Why do you think it's hydro locked? Have you checked the battery? Check the connections and see if you have power to the starter before you get too excited. Does it clunk when you hit the starter or just not turn over. What kind of noise is it making? And when you say it is fresh water cooled are you saying it is a closed system?

 

[tpenfield]

Re: Appears to be hydrolocked

The water from the muffs cannot pass the sea water pump unless the engine is running. So, the thought of leaving the hose on after stopping the engine should not be of concern. Just to be safe, if you want, take the spark plugs out and try turning the engine over.

 

[CurrentObsession]

Re: Appears to be hydrolocked

It was hydrolocked.

Pulled the plugs on the starboard side and while pulling the 3rd one out gushed alot of water. Cranked the water out, replaced the plugs and she runs like a champ now. Even took her out on the lake for some late season fishin. But what would cause this? Bad exhaust manifold? To answer an earlier question, it is not a closed cooling system.

 

[tpenfield]

Re: Appears to be hydrolocked

Yes, exhaust manifold/riser/elbow would be the things to check.

 

[CurrentObsession]

Re: Appears to be hydrolocked

What would I look for? I suspect 9 out of 10 times it is the gasket that fails not the metal?

 

[lmorefield41]

Re: Appears to be hydrolocked

What would I look for? I suspect 9 out of 10 times it is the gasket that fails not the metal?

Check to see if the gasket is blown, if the riser has any rust/cracks/evident damage,etc. You also want to get some kind of lubricant, WD-40, in the cylinders so they do not rust. If they rust, you run the risk of seizing the engine. If you can, it'd be worth it to dry the cylinders out to make sure all of the water is out of there. Trust me, it can get ugly if the water rusts the cylinders and bores.

 

[TilliamWe]

Re: Appears to be hydrolocked

What would I look for? I suspect 9 out of 10 times it is the gasket that fails not the metal?

Not with this: "1999 5.7 liter with a BIII drive." Your exhaust manifold or riser could very easily be rusted out internally. My 1997 had stainless steel risers with iron manifolds. The risers looked great, but the manifolds were showing signs of rust back in 2005. So you could be due.

 

[boat1010]

Re: Appears to be hydrolocked

I still stand with what I said earlier. It isn't having the muffs on and the motor not running.. I would run a compression check and see what you find.. The reason I asked if it was a closed system is you said it was fresh water cooled.. Smiling, that is only if you are in a fresh water lake... It could be a head gasket or manifold gasket.. Hard to say. But a compression check should give you an idea where to go from there.. and for sure if you don't do something with it this winter you need to make sure there isn't water in it so it will rust.. like was said earlier get some oil in there so it doesn't rust.. But if it were mine I wouldn't let it go over the winter. There is a problem some where so might as well get it fixed so it is ready to go next summer..

 

[CurrentObsession]

Re: Appears to be hydrolocked

So is the following the logical way to approach this:

1. If I do a compression test on each cylinder and I have a significant varience, I should suspect something is wrong with the heads like a head gasket or valve issues.

2. If compression test comes back okay, assume the issue is probably with the risers or exhaust manifolds and associated gaskets.

 

[tpenfield]

Re: Appears to be hydrolocked

I recently had the same issue, but my engine never hydrolocked. The water from the elbows would slowly leak into the exhaust manifold and accumulated at the exhaust ports of the middle 2 cylinders on each side. The rust was clearly evident when I took the manifolds off.

The water also seeped into the exhaust port of those cylinders; #4 & #5 being the worst, causing the valve seats to become rusty & pitted.

Before I tore things apart, I did a compression test, and it came back OK. Then I did a leak test and that showed the problems with the middle cylinders. #4 & #5 had about 50% leakage and #3 & #6 had about 30% leak. The others were less than 10% leakage.

Based on the 50% leakage, I knew that it needed a valve job. Once I took things apart, I was able to 'connect the dots' and see that leaky manifold/risers caused the whole mess.

 

[HT32BSX115]

Re: Appears to be hydrolocked

1999 5.7 liter with a BIII drive. Fresh water cooled.

Just got back from the boat launch, engine would not turn over. Ran fine on muffs yesterday, didn't turn off the water until about a minute after shutting the boat down. I know you can't run the hose on a jetski engine while it is not running, but didn't think it was an issue with an I/O??

Howdy,

It should not be a problem.

What do you mean by "Fresh water cooled"? CLOSED-COOLED with a heat exchanger and 50/50 mix of anti-freeze?

while pulling the 3rd one out gushed alot of water

Clear water or 50/50 Anti-freeze mix?



If clear water, and you're closed cooled, then you could have a riser/riser gasket leak.

If raw water cooled, it could be a manifold, riser, or riser gasket leak OR head gasket leak (although less likely)

 

[TilliamWe]

Re: Appears to be hydrolocked

HT reread his other post on here. It is raw water cooling, he misused a common phrase that most people misuse. He doesn't have antifreeze anywhere near his engine. He does NOT have closed cooling.

gWhen one has water in the cylinders of a marine engine the first thing to check is the exhaust manifolds. Sure, you can do a compression check, but reacinh the spark plugs may not be any easier than removing the manifolds. And even though it's most likely NOT a headgasket problem, you have to remove the manifolds to fix that. So remove the risers now, and I'll bet you a nickel you find your problem. Bad exhaust manifolds/riser.

 

[duped]

Re: Appears to be hydrolocked

I would second the manifolds. Otherwise I have also heard of larger boats taking water into the cylinders through the exhaust at launch, but I have never seen it myself...

 

[CurrentObsession]

Re: Appears to be hydrolocked

Sorry for the confusion, it is raw water cooled. I should have used the word raw instead of fresh on my original post.

Thanks for all the input, I will have to deal with this come springtime.

 

[86 century]

Re: Appears to be hydrolocked

Did the eng diesel or run on when you shut it down. Or something as small as that half turn backwards as it dies can suck water from the exhast into the cly.
I could be way of just that if you have a leaking riser or manifold it should do it every time.

 

[CurrentObsession]

Re: Appears to be hydrolocked

Did the eng diesel or run on when you shut it down. Or something as small as that half turn backwards as it dies can suck water from the exhast into the cly.
I could be way of just that if you have a leaking riser or manifold it should do it every time.

No it did not diesel....everything seemed normal when I shut her down.