Could this be hydrolock?

[sidechoke67]

I was on the water last weekend, came to a stop, and turned the boat off. The engine ran-on for about 1 second...nothing awful, but not a clean stop either. Next time I turned the key, I get a clunk sound. Sounds a lot like hyrdolock so far, I know. Well, I've had issues with my current starter since I bought it last summer. I turned the motor by hand, maybe 1/2 to one full revolution (without removing the plugs), and it turned freely. While turning it by hand, I *think* I hear a click from the starter area...in my mind I envision the bendex coming free of the flywheel based on the sound, but I'm not 100% sure that I heard anything really. So, I try to start the boat again, and it starts right up. Ran fine for 1/2 hour, docked for a bit, started it again, and again started right up.

I am asusming my problem was not hydrolock because:
1) with hydrolock, I am assuming I would not have been able to turn the motor easily by hand without removing the plugs
2) if it were hydrolock, I wouldn't have solved the problem by turning the motor by hand

Does that sound reasonable? I replaced my original Volvo starter last summer, with another brand last summer, and have had mis-alignment issues since then. I am assuming I have a starter issue, but don't want to rule anything out.

FWIW, once I got my boat home, I did pull the plugs and turn it by hand. Nothing came out - but I don't know if this was a valid test at this point since the engine had run for awhile after my original problem.

Thanks for any thoughts.

 

[Bifflefan]

Re: Could this be hydrolock?

Sounds like your dead on.

I think the starter has a dead spot or bad bendix, maybe both.
Dont buy a new/rebuilt one, have the one you have rebuilt. You will get a much better result. And save some money.

 

[John_S]

Re: Could this be hydrolock?

If you turned it over by hand immediatly after it happened, then I would think maybe starter. Regardless, the engine run-on is a problem, and will cause hydro-lock. This can be timing, carb adjustment, and/or just not idling long enough before shutdown.

If you have the run-on again, and the same issue, remove plugs asap, and then try turning over looking for water out the plug holes.

 

[sidechoke67]

Re: Could this be hydrolock?

Thanks guys.

imported_John_S, yea, I wish I had thought to pull the plugs when it happened. Next time, I will for sure, thanks.

 

[sidechoke67]

Re: Could this be hydrolock?

bifflefan, I haven't been able to find anyone that will rebuild a marine starter. I know a number of places that will rebuild auto starters, but nobody wants to crack open the seal on a marine starter..

 

[boltonranger]

Re: Could this be hydrolock?

try here:beiterbattery.com
they rebuild marine electrics

 

[HT32BSX115]

Re: Could this be hydrolock?

FWIW, once I got my boat home, I did pull the plugs and turn it by hand. Nothing came out - but I don't know if this was a valid test at this point since the engine had run for awhile after my original problem.

You'e right. It wouldn't be a valid test.

If your risers have been on there for a while and you have a slight riser gasket leak, you still could be getting slight amouts of water leaking into an open exhaust valve.

I had that very problem with my previous OMC 460 King Cobra. The engine would hydrolock briefly if I tried to start it up to about 30 min after shutdown. If I waited longer, it would crank right up easily.


I found both side riser gaskets leaking slightly at the sealing surfaces.....It had been doinf it for a couple of years.

It always seemed like the starter was dragging etc. There was nothing wrong with the starter.

Whether you replace the starter or not, if you have not removed your risers for inspection in the last few of years and replaced the gaskets, you probably should soon. If you're running in salt it should abolutely be done. If you're "Fresh water" only, you should still do it every 5 years or so just to catch it before they start leaking. (mine went around 10 years before they started leaking.....there was rust in a few of the cyls from sitting with water in them)


Regards,


Rick

 

[sidechoke67]

Re: Could this be hydrolock?

Thanks HT32BSX115.

So...do you think it is possible that I got just enough water in there to prevent the motor from turning over with the starter...but still a small enough amount of water that could find a way out with me turning the motor over (easily) by hand?

If it was hydrolock, it seems weird to me that the starter motor couldn't turn the motor over, but I could turn it over easily by hand. That said, I'm no mechanic, and someone else pointed out that when you turn it by hand, you are turning it slowly, so maybe any water had a better shot at finding an escape route?

The riser gaskets are original as far as I know. Boat is a 2001 that I've owned since 2007. Fresh water only. Either way, I appreciate the advice on checking/replacing the gaskets.