Engine siezed after hydrolock

[Murph1966]

Back story: Twin Engine Sea Ray 290 SLX. Port engine has been running a bit hot at times over the past year even after installing new water pumps, etc. Not consistent but at higher rpm. Operates fine at low and mid range rpm. After a day on the water with lots of people on swim platform we returned home. ( I've read that too many people in the back of boat can cause water intrusion) Engine ran fine for the 20 min journey back home. At docking and at idle the engine quite. Attempts to start did not work and the engine chugged a few times then just a click. Parked the boat and called our mechanic who was too busy to get to our boat right away. Boat sat for a few days before they sent a tech out to assess the problem. He pulled the plugs and found water on one of the cylinder heads on one side only and only in one cylinder. He was able to manually rotate the engine but it was stiff.

Boat then sat for two weeks waiting for the boat shop to get to us. Neither the tech or the shop owner/mechanic never put any lubrication in the cylinders or recommended that we do so. Which, as I've now read, is critical in preserving the engine! Seriously? Boat is now at the shop and they found a cracked exhaust manifold but cannot get the engine to rotate manually in either direction. They sprayed some kind of corrosion eating lubricant into the cylinders (Krull? sp?) and it has been soaking for several days with no luck.

I'm really disappointed that this very reputable shop did not advise me to lubricate those cylinders while it sat. I've read here that they should also consider removing the starter, but they haven't done that yet either even though they do know its shot. Apparently they found parts of the starter in the bilge! I really don't want to have to pull this motor.

OBTW, the starboard motor is operating just fine. I've never had any issues with this motor. Mechanic did say that that motor has had both exhaust manifolds and risers replaced sometime before I bought the boat last summer.

1. What do you think is the cause for the water intrusion? Cracked exhaust manifold? Considering that the starboard engine is fine I'm doubting it was too many people on the dive platform during the day.
2. What would cause a starter to come apart?
3. Should they remove the starter and then try to rotate the engine? I've read here that this could be a seized starter that could lock up the rotation?
4. What other options are there to free up the engine before having to pull the motor?

So, I made the mistake of not researching this myself soon enough. That's on me, but to not tell your client to take critical steps in preserving the engine is really disappointing.

Thanks in advance for all your help!

 

[Bondo]

Ayuh,.... Welcome Aboard,..... Do ya boat in freshwater or brine,..??

These forums are for Diyer's, not to whine 'bout mistreatment at marinas,...
If you wanta fix yer boat, We'll walk ya through it,...
But, it sounds like you pay others to do yer work for you,...
#1,... Yes, busted manifolds will do just that,...
#2,... Who knows, probably because you were tryin' to start a hydro-locked motor,...
#3,... As noted above, I ain't here to 2nd guess yer choice of mechanics
#4,... Ditto #3,...

 

[Bt Doctur]

What you should have done was fix the overheating issue first. Thats what started this episode most likely. Once you suspected a hydrolock you should have:
removed the spark plugs, drain the block, drain the manifolds, spin the motor to clear the cylinders.
Remove the water inlet from the T housing and direct to a safe direction and run the motor for 10 or 15 second intervals to dry the cylinders.Be mindfull of the rubber components.
With most salt water hydrolocks you have 48 hours to get it dry and running. Fresh water hydrolocks a bit longer
1 bad riser, manifold, head
2 starters dont normally come apart on there own
3 Remove the drive, remove the starter, install T bar in housing and turn motor manually
4 Not many, easier to pull and bench repair than working inside a engine compartment

 

[Scott Danforth]

Welcome aboard

no excuse for your lack of responsiveness as a boat owner. your job is to know every inch of every system in your boat regardless if you do the work yourself or pay others to do the work.

as others pointed out, could have been a number of things that lead to hydrolock. your actions trying to start the motor most likely not only broke your starter, however bent your connecting rod. the fact that the motor sat for weeks with water in it means that the motor needs a full rebuild.

and yes, i've been accused of pulling band-aids off quickly

 

[tpenfield]

I got my $5 bet on a bent connecting rod from the hydro lock that is keeping the engine from rotating.

Engine is probably coming out of the boat, if it is a bend rod, then the lubrication would not have mattered.

 

[Murph1966]

Thanks all for the blunt truth! Ouch! Agreed, I should have done the research up front and made some better decisions. The boat is in fresh water. I do pay others to repair our boat as I do not have the expertise nor the time so I do rely on their judgment and guidance. This was the first time I have experienced this particular issue with any boat but I'm certainly much better informed and educated thanks so some of these posts. Time will tell next week! Thanks again for your feedback.

 

[Murph1966]

One other quick question: If it were a bent rod would it have rotated manually initially?

 

[Bt Doctur]

without removing the drive and inserting a T bar that cant be answered. could have starter parts jamming the flywheel.
Yes, slightly bent con rods do rotate

 

[tpenfield]

I had a hydro-lock that bent a connecting rod (or two) . . . the starter could spin the engine (with a thumping feeling), but I could not manually turn the engine past the point where it got stuck. Decided at that point to pull the engine and tear it down. I think a couple of the pistons had bent rods

 

[Murph1966]

Thanks very much folks!