Submerged 4.3 Mercruiser

[Hogstrangler]

Need some help guys. My 21 foot Tracker Tahoe was trailered and parked with the plug left in it. Fun story for later. But for now..
4.3 Mercruiser I/O was mostly submerged for about two months. Carburetor not submerged.
Drained the oil/water, pulled the plugs.
Is this engine trash?
What should happen now?
Thanks for any help.

 

[jimmbo]

This should be in the Mercruiser section.
How much water drained out with the oil? Was it clear or rusty?
You really only have two options; Pull the engine and inspect the crank, cam, and cylinders for rust, or, refill with fresh oil, run it, drain it and repeat a couple more times and see what happens. If the bearings were damaged it will soon make it known with knocking sounds followed eventually by failure

 

[Alumarine]

I'm assuming fresh/rain water?

Get it running, the sooner the better.
As jimmbo said, change oil and filter (cheap is good), run it up, repeat.

Also be prepared to replace starter and maybe alternator.

 

[jimmbo]

I forgot about the starter. Mine needed to be checked over after I submerged it, but that was 13 yrs ago

 

[Hogstrangler]

Thanks guys, I will certainly get it in the correct section next time.
I really appreciate the info and Ill answer your questions here, too.
Its rain water, and several quarts of it. I couldn't tell if it was rusty.
Ill follow your advice and let you know the outcome!

 

[Scott Danforth]

water in it for 2 months..... plan on buying a new motor, however you may get lucky, however odds are against that

to get several quarts of water in the engine, the intake and carb would have had to have been submerged at one point. most likely the water level was higher than you think

start it up asap as jimmbo indicated. if the motor starts knocking, you toasted the bearings because the crank is rusty.

that much water in there, the outdrive trim pump was under water too as well as the trim tab pump. plan on replacing those. your starter will be failing shortly, plan on replacing it and the alternator. your wiring harness should be fine because the fresh water. however your power steering pump is probably full of water and the steering cable as well.

you have water in places inside your boat that were never intended to have water in it

while your at it, if the temp froze at all with the water in there, you may have damaged other things on your boat too such as the flotation foam, etc.

 

[jimmbo]

It just keeps getting Rosier and Rosier by the minute!

 

[Alumarine]

Insurance maybe?

 

[Bondo]

Drained the oil/water, pulled the plugs.

Ayuh,.... Welcome Aboard,..... How Much water, 'n oil did ya drain,..??
How did ya drain it,..??
How high on the motor is the outside the motor/ in the hull waterline,..??
Did ya try to turn it over with the spark plugs out,..??
Did water go down the carb throat, or did the hull fill with water, Around the motor,..??

Dependin' on the water level outside the motor, ya might get away with just a new starter, alternator is the next to go swimmin',....
Then the bellows fills, so pull the drive, 'n check that,...

Answer a few of these questions, 'n We'll get ya runnin' again,.....

 

[achris]

If the water was above the crank level, the bellows will also be full. Replace Gimbal bearing, unis and probably yoke seal surface will need a speedi-sleeve.

DO NOT turn the engine over before you pull the drive.

 

[Hogstrangler]

I apologize for being away so long. Im a military guy and had to attend some training for a few months.
Heres the update and Ill answer as many questions as I can.

Replaced the spark plugs.

I drained the oil 3 times. At Number 4 the oil stopped looking like chocolate milk.

Started it and it actually sounded ok. Got it up to temperature. Checked oil, looks good.

Trim pump died, as predicted. I have one ordered.

That's all Ive been able to do to it. I just got home and Ill get on it again this week. I wasn't able to get in the water. Life and the military happened simultaneously, and the boat was way down on the list, unfortunately.

I have plans to pull the outdrive, check (and probably change) the gimble bearing, flush the trim pump lines, change outdrive oil. Just for starters.

I moved to Fredericksburg Texas, so if anyone knows a good mechanic in this area, I would appreciate it.

In the meantime, I hope to be home for a few weeks working on it, and Ill try to keep everyone updated.

Here a some answers to the questions I saw.

Engine was half submerged when I discovered it. The carb didn't seem to be affected.
First time I drained the oil, there was a significant amount of water, didn't measure it, but it was mostly water for a minute or two until oil started coming out. Alternator is high on the motor and didn't get wet.
I turned it over with spark plugs out.

It was rainwater that filled the boat, but that was because the plug wasn't pulled after last use by a friend.

So the engine also had saltwater in it for two months. Double

Will let you know. Thanks again for the help.

 

[achris]

Without pulling the engine and stripping it down and checking everything, then replacing everything electrical, including the harness, that engine will be plagued with problems for years.

Sorry to be the bearer of such ill tidings.

Personally, your friend should be stumping up the funds for all this.

Chris.