Dead Engine?

[92searay]

I was boating today, boat was running great. We were pulling a tube, not a large one, and we have pulled the tube for 3 year with no issues. We were moving along and all the sudden the engine just dies. No major noises, oil is full and clean. Engine will not crank, starter engages and tries to turn engine over. tried jump starting with no luck. Got the boat home and tried to turn the engine over by hand, and it wouldn't budge, the bolt just kept tightening. I am an ASE and Ford Certified automotive technician, with the amount of force i am putting on the crank bolt, it should turn over. I have a couple questions, one is can this engine get hydrolocked while driving? is there something in the outdrive that could cause this? I am able to do anything mechanical wise, I just need a starting point for diagnosis. Thanks!

The boat is a 1992 Sea Ray overnighter, with a mercruiser 5.7L and ill have to double check, but im pretty sure it has a bravo 1 drive.

 

[terminaldegree]

I'm certainly no tech, but I'd at least go through the motions if there's a possibility of a hydrolocked motor-- pull the plugs, try to crank the motor to blow the water out and fog the cylinders. At least you'd know if the problem was more serious if the motor still didn't crank.

If you think it is hydrolocked, you should probably act very quickly to avoid further damage. Again, just a layperson's opinion.

 

[techmitch]

Yep, pull the plugs and try to turn it over A.S.A.P. If it still doesn't turn over put the shifter in forward and pull the drive off. It's only 10 nuts, 6 that hold the drive on and 4 that hold the trim cylinders on. Now try to turn it over again. If it won't turn over now....................well you know to do. Below are links that should help. Welcome to CSR from another A.S.E and Ford/Lincoln/mercury Certified Master Technician. Also please post back to let us know what you found and to help others in the future.

http://mercstuff.com/drive_id.htm

http://mercstuff.com/alpharemoval.htm

 

[92searay]

If it is hydrolocked, is it common for the headers to crack? and if someone could point me in the direction of how the heat exchangers work, i would greatly appreciate it.

 

[techmitch]

Headers? Heat exchanger? we are going to need some more info. or pics of your type of cooling/exhaust system.

 

[92searay]

Well the engine isnt hydrolocked. pulled the plugs and engine still wont turn over. Going to tackle the outdrive next and remove it and check the double cardan joint. and the outdrive. is there any special precautions i should take?

I dont know what there called. i just would like to know more about the heat exchangers/ headers. theres water hoses running to the top of them.

 

[Bt Doctur]

all inboard and indoard/outboard use water cooled manifolds and risers. a 1/2 system is engine only with A/F and seawater for the manifolds and risers, a full system has A/F in the manifolds also .A blockoff plate is used and seawater cools the riser.
The heat exchanger has seawater flowing thru a core that contains the A/F .similiar to a car radiator using air to cool the A/F
Have you checked the oil level in the drive?

 

[92searay]

yes, i actually just replaced it a few weeks ago with royal purple. i put in the rec. weight, i cant remember what it is right now though. but its clean/full oil. im going to remove the outdrive when i get a chance, just trying to familiarize myself with the procedures and everything about it.