Submerged mercruiser

JCFERG

Seaman Apprentice
Joined
Sep 22, 2003
Messages
32
I recently purchased a 2001 boat with a 3.0 liter mercruiser engine and outdrive. I was told by the previous owner that the boat filled with rain water while on the trailer and the plug was still in the boat. The water line is half way up the engine. I was told the engine could be turned by hand with a wrench.

How can I turn the motor by hand? Is it at one of the pullies in the front of the engine? I need to get alot of leverage in case the motor is seized. I have read the posts on how to restore a submerged engine. I want to turn the motor every day or so until I get time to really work on it.
Thanks for the help
 

Dakota47

Senior Chief Petty Officer
Joined
May 22, 2007
Messages
722
Re: Submerged mercruiser

Turn it at the Crank, Bottom pully.
 

JCFERG

Seaman Apprentice
Joined
Sep 22, 2003
Messages
32
Re: Submerged mercruiser

How do you get anything in there to turn it?
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: Submerged mercruiser

I hope the oil has been drained, refilled and the engine run. If there is water in the crankcase, no hand turning is going to save the motor! Additionally, I would be suspicious that everything under the floor is soaking wet and liable to cause the floor (and more) to rot from the bottom up.
 

wncrjb

Petty Officer 1st Class
Joined
Aug 29, 2006
Messages
253
Re: Submerged mercruiser

IF you try turning it by the bolt inside the vibration dampner, DON"T use too much pressure or you could snap the bolt off in the crank.

wncrjb
 

bjcsc

Lieutenant Commander
Joined
Jun 1, 2006
Messages
1,805
Re: Submerged mercruiser

I'm with Boomyal. If it has not been running since it was trailer sunk, it's already toast and there's no need to try to turn it at all. You literally have hours to get the water out in order to save it...
 

Flukinicehole

Petty Officer 1st Class
Joined
May 29, 2004
Messages
365
Re: Submerged mercruiser

I'm with Boomyal. If it has not been running since it was trailer sunk, it's already toast and there's no need to try to turn it at all. You literally have hours to get the water out in order to save it...

This is not true dont scare the guy away. You should tell him to pull the dipstick and look for water in the oil. Do you see any? If no and the engine turns over by hand you should be O.K. I`v seen many boats with water above oil pan (salt water) and the engins are fine. You should have no oil in the engine if your gaskets and seals are good. Floor rotting in a few years is possible but come on and steer the guy in the right direction.
 

bjcsc

Lieutenant Commander
Joined
Jun 1, 2006
Messages
1,805
Re: Submerged mercruiser

This is not true dont scare the guy away. You should tell him to pull the dipstick and look for water in the oil. Do you see any? If no and the engine turns over by hand you should be O.K. I`v seen many boats with water above oil pan (salt water) and the engins are fine. You should have no oil in the engine if your gaskets and seals are good. Floor rotting in a few years is possible but come on and steer the guy in the right direction.

First, I agreed with Boomyal's post which said:
If there is water in the crankcase, no hand turning is going to save the motor!
To me, this advises to check the dipstick/engine for water.
Your statement assumes that no water made its way into the engine, which certainly is possible and probably is more likely to be the case in most similar scenarios. If, in fact, that were the case, yes, the engine could be OK. In fact, it would be running. But, the PO said the engine could be turned by hand, which is a given (and irrelevant) on a running engine, or an engine that has not seen water, i.e. they will all turn by hand. The fact that the PO made that statement and that JCFERG referred to it as a submerged engine and inquired about getting a lot of leverage to hand turn it all lead me to believe that water made it in. In my opinion, (which is what I have to offer here) it's not worth rebuilding non-exotic (most) marine engines with the damage that results from untreated water intrusion.

I'm not trying to scare anyone and advising not to waste time/money/energy can be as much of a "steer in the right direction" as specific instructions in my experience...
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Submerged mercruiser

Ayuh,...........

If you take the Spark Plugs Out,+ the Outdrive Off,.....

The motor should turn easily by Hand........

And,....... Just Looking for Water on the Dipstick isn't enough,.....
If you only see Oil,..... Is the oil level Higher than it should be,..??.....
That'll be because there's Water under the Oil......
If that happens to be the case,.... Drain it immediately,+ refill with oil.....
 

imported_TheMan

Petty Officer 1st Class
Joined
Oct 19, 2006
Messages
224
Re: Submerged mercruiser

The question is how to turn the engine over, not whether he can save it.. If he wants to try, you don't need to discourage him. Anyways, the real issue is the mounting.

The 3.0L is center mounted, he isn't able to get to the crank pulley with the way it is. He will have to remove the engine to really be able to turn it over by hand. The other option is to block the engine up and remove the front engine mount, or put the front on a hoist and remove the mount. This will expose the crank bolt. (Unless there is a slot in there I am forgetting about, but I don't remember having one on my old 3.0L...)
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Submerged mercruiser

Ayuh,......

With the Spark Plugs Out,+ the Outdrive Off,......

You can just grab the Belt,+ roll it over....................;)
 

Mkos1980

Chief Petty Officer
Joined
Oct 25, 2007
Messages
640
Re: Submerged mercruiser

Ayuh,......

With the Spark Plugs Out,+ the Outdrive Off,......

You can just grab the Belt,+ roll it over....................;)


Ditto, but I use strap wrenches on another pulley
 

a70eliminator

Captain
Joined
Sep 9, 2007
Messages
3,688
Re: Submerged mercruiser

Why not just bump it over with the key ignition? That will tell you if it's seized, unless you have a bad starter.
 

heyttown

Chief Petty Officer
Joined
Aug 3, 2003
Messages
537
Re: Submerged mercruiser

water that high, the starter is probably junk, along with maybe the alternator.....Buddy had a 3.0 and did the same thing...Luckily oil was clean and was changed as soon as it was noticed, but that didnt help the starter alternator, and I believe battery, and maybe even his trim solenoids...I forget but it was a costly mistake
 

dmcb

Petty Officer 3rd Class
Joined
Oct 13, 2007
Messages
93
Re: Submerged mercruiser

I wouldn't be quick to write off any engine.
A story.
The owners of my marina in Michigan bought a salvage boat in Florida.
36 or 38 trawler with twin diesels.
It was completely under salt water with hurricane damage.
It was not pickled.
It set that way for perhaps a year.
Engines removed. Pistons siezed in the sleeves and had to be driven out.
New sleeves.
Now the good part.
When the rod bearing and main bearings were removed, the crank was shiny clean. No rust a all.
New sleeves, pistons, brgs, rings and the engines are running.
So if the pistons are free maybe the engine can be saved.
Doug
 

wire2

Lieutenant Commander
Joined
Jun 25, 2007
Messages
1,584
Re: Submerged mercruiser

Another story;

I had a '93 Intrepid roll down a small hill into the water at 05:30 am, (Key to shifter interlock was defective, not in Park). The front of the car was in the water but not over the rear throttle body. It was over the oil fill cap so there was water intrusion.

A flatbed pulled it out, took it to a body shop, (only place open at noon, Saturday). They drained several gallons of water, then oil from drain plug. Put in fresh oil & filter, started it.
It seemed fine, other than erratic gauges. I drove it several times in next few days, as wiring dried, electrics working again. Then on way home with ~100 miles since dunking, a bang, something hitting under the floor & huge billows of smoke & steam behind me.

Turns out the water had crept into the crank bearings and stayed there even with an oil change. Eventually the bearing spun, grabbed the con rod, broke it off & punched a hole in the block, dumping all the oil & anti-freeze on the ground.

Afterwards, an experienced mechanic told me a trick I could have used to save it.
Remove the oil pressure sender, put a fitting on the engine and pump 5 qts of oil in while turning the engine a bit at a time (but not starting) with the key. That probably would have pushed the water out of the bearings.

Mail0045.jpg


I had thought of putting a sign up; "Free car wash with valet parking"
 

thrasher

Chief Petty Officer
Joined
May 23, 2007
Messages
443
Re: Submerged mercruiser

You where lucky that no boat was moored there at the time.. The car might not have gone in the drink, but you would have a nasty boat repair bill!!

Nice picture.. I would love to live that close to my boat dock!!

Gary
 

wire2

Lieutenant Commander
Joined
Jun 25, 2007
Messages
1,584
Re: Submerged mercruiser

You were lucky that no boat was moored there at the time.. The car might not have gone in the drink, but you would have a nasty boat repair bill!!

Nice picture.. I would love to live that close to my boat dock!!

Gary
Lucky is an understatement. Sometimes there's people camping in tents on the grass, could have been tragic.

Chrysler put out a safety recall on the defective interlocks after this happened to me, turns out several people had similar mishaps with cars rolling away.

My insurance went after Chrysler for costs, I dunno what happened with it.

The water in the pic is a lagoon connected to Buckhorn lake on the Trent-Severn Canal system in Ontario, Canada.
 
Joined
Jul 27, 2007
Messages
7
Re: Submerged mercruiser

Don't write off any boat just yet. I bought a 76 Muskie 3.0 Mercruiser last spring that was under water for a week. The guy I bought it from let someone test drive it for a weekend and the guy put it in without the plug in and didn't call for a week to let him know where the boat was. There was water in the oil, the floor in the back was water logged and the starter was rusted tight when I got it. I drained the oil ran #2 diesel fuel for 2 or 3 minutes drained that and dumped in 30w oil. I changed the oil 3 more times after running it for several minutes each time and It ran good all last summer. Almost a hundred hours worth last summer in fact. The starter All I did was pull it apart, cleaned everything really good and put new brushes in it. The floor in the back will be getting replaced this spring, but what do a couple of pieces of treated plywood cost.
I believe for the right price any boat may be worth a little work.
 
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