Hydrolocked engine

[Sioux60]

I have a 1995 Sea Ray Bowrider 200 Signature with a Mercruiser 5.0 V8. I pulled the plugs on the engine and was able to turn it over. It appears that all 4 cylinders on the starboard side had water in them. I assumed that the exhaust shutter had failed on thatnside of the engine, but upon pulling it apart I found no shutter. For this vintage of a boat was an exhaust shutter standard, and did it break apart and fall further into the ‘Y’ of the exhaust system? Should I put new shutters in?

Thanks for for any insights.

 

[AShipShow]

Yes, there should be a shutter there. I would pull the drive, because the pin that holds it is most likely stuck down around the bottom of the Y Pipe or shift shaft. You should replace the shutters. If you took a big wave to the back of the boat or went in reverse fast enough, that COULD be your source of water... However, more likely is you may have a damaged block or riser/manifold.

You should probably do a leak-down test to see if you have a cracked block or exhaust.

 

[Sioux60]

Thanks for the reply. The last time I hadn’t it on the water I had no issues. I went to start it up on the driveway, and couldn’t get it to turn over. I’m assuming it hydrolocked somehow when I shut it down? I’m hoping no serious damage was done due to it not being in operation at all. I’ll pull the port side exhaust to see if there is a shutter there. I was mainly wondering if for some reason there may not have been a shutter. Additionally, what else should I be doing to ensure I’ve gotten all of the water out of the engine? Outside of an oil change, should I spray anything into the cylinders?

Thanks.

 

[AShipShow]

When you pulled the plugs and cranked the motor, did you see water shoot out of the spark plug holes? How positive are you there was actually water in there?

At a minimum, I would pour a little motor oil in each spark plug hole and crank the motor a few times to try and coat the walls so they don't rust... Before you crank the motor tho, i would pull the drive so you don't need to hook up water to crank it. If you crank it on muffs, you may risk refilling the cylinders with water. Odds are, you're going to need to pull the drive to get to the bottom of the problem anyways cuz it sounds like the motor is coming out.

 

[Sioux60]

I’m positive. Plugs were wet on the starboard side, with water running out of one of the plug holes when the plug was removed. Upon turning over the engine, water shot out of plug holes. Oil to prevent rust was my thought too. Because it appears to be only the starboard side, would that lead you to believe exhaust shutter, or not necessarily?

 

[AShipShow]

Not necessarily. Would lead me to believe its more likely a riser/manifold problem. But its hard to say anything more definite without more details. If its a new problem, it would rule out a improperly winterized motor which would have been my first guess.

I would pull the riser/manifold off that side and do a leak check. There is a procedure in the ADULTS ONLY section for leak testing risers and manifolds.

 

[tpenfield]

Oil into the cylinders.

Spin the engine to lube the cylinders and purge any excess oil/water

See if the engine spins freely (checking for any bend connecting rods, etc.)

Run a compression test

Run a cylinder leak test.

See what you got for results.

 

[Sioux60]

Thanks for your insights. I’ll proceed as recommended and hope for the best.

 

[Bondo]

Additionally, what else should I be doing to ensure I’ve gotten all of the water out of the engine? Outside of an oil change, should I spray anything into the cylinders?

Ayuh,..... Welcome Aboard,..... Start it up, 'n run it a couple minutes,...... ASAP,......

 

[Sioux60]

So I pulled the risers. They look pretty rusty, lots of flaking, water in both sides of exhaust. I’m thinking time to replace. Should I pull the exhaust manifold too? Additionally, I found half of the exhaust shutter in the port side, so obviously it had them. So the drive has to come off to get the starboard side to get the shutter debri out. Let me know if there are other suggestions for me. Thanks.

 

[Sioux60]

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[Sioux60]

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[Rick Stephens]

With that much rust and scale built up, you need to pull the manifolds off and check them. They are likely source of water in your cylinders, especially since all that one side was wet. Most likely it is time to replace the manifolds risers elbows.