2024 Honda 8hp Outboard sank

[dwpsco]

So we had a bit of a storm and my dinghy sank with my brand new 2024 Honda 8hp Outboard on it.

Got it all back, drained the oil from the outboard, new oil and filter. I can start it now, but the Green oil light don't come on and after a minute or so the low oil pressure safety kills the engine. (as it should) BUT,I do have oil pressure and flow. I took the oil pressure sensor out and tested it, 14.1 ohms, added pressure and the ohms go up. Oil comes out of the sensor hole on the engine. Could it be the IGNITION CONTROL (CDI)? The CDI runs $250 and if it isn't the problem I don't really need a spare lol. OR is the engine just toast and I have to buy another new outboard.

Anyone got any ideas?

 

[DavidM]

In my limited experience, once an engine is dunked in salt water, problems keep coming back- different ones as the salt continues to corrode circuits even if nominally dry.

David

 

[dwpsco]

I was afraid of that

 

[C lectric]

What exactly did you do to the engine to get it to run again?
You may NOT have removed all the seawater. Seawater is conductive so unless you removed ALL of the seawater it may be shorting somewhere in the system killing the engine.
You may need to do a couple of oil changes.
Did you check the oil pressure with a PRESSURE GUAGE?
I have been involved with recovering a couple of seawater soaked engines. We dumped the fuel ,ALL OF IT. pulled the carburetor and cleaned and resealed it.

Cleaned the ignition system and ran the engine. However they were Yamaha 2 cycle engine about 20 years old at that time.
Did you fresh water flush, almost drown) the engine? If any traces of seawater remain they can cause shorting. It takes very little time for seawater to get where you don't want it so the rinsing must be done immediately.
If you have an electronics card control then you may have to replace it.

BUT, i don't really know what is wrong with yours, just some tips at what to look for and do

You may need to take it to a repair shop.

 

[dwpsco]

I rinsed it off very well with fresh water, drained the water out of the carb, Changed the oil and filter, put new fuel in her and she started. She does get up to temp, But no I don't have a pressure gauge.

 

[Martin610]

Over the years I have had a couple of 4 stroke outboards get dunked. With both a Mercury (tohatsu) 3.5 and a Suzuki 2.5 I retrieved them and rinsed them. Drained fuel. Removed spark plug and sprayed the engine with copious amounts of WD 40. Both of them still running well after many years.

In the case of the Honda you may have a sensor or something that doesn't like salt water and may require a trip to the dealership.

 

[Larry M]

Some of the electrical connectors are slip/snap on. Take them apart and use a quality electrical contact cleaner such as CRC Contact Cleaner and Protectant.

 

[High Wire]

I was afraid of that

Don’t give up yet. That minute or two it runs, get some fogging/storage spray down the air intake. Pull the plugs and spray in there too. Spray everything electrical. I would get it to a dealer for service asap for anything you missed like underneath the flywheel.

 

[Blissboat]

So we had a bit of a storm and my dinghy sank with my brand new 2024 Honda 8hp Outboard on it.

Your avatar shows only that your location is "USA." Are you in a part of the country where the water is fresh, or salty? If you're feeling sociable, perhaps you'd tell us roughly where you do your boating - always helpful to know when making recommendations. In my home waters of northeast Florida, the Honda outboard dealership network is weak. Expertise is scarce (I've only found one knowledgeable factory service technician in the region) and parts are stupid expensive and slow to arrive. I've owned two Honda outboards, but now I avoid the brand.

That said, Larry's suggestion about going after everything thoroughly with CRC is a good one, along with being patient about drying out the hidden places.

 

[C lectric]

Oil pressure guages are about $20.00. I suggest you should have one along with a few fittings for adapters and a suitable pressure hose.

Did you drain the fuel tank for removing any water that entered. Tanks have air vents but water can enter if submerged. So even though you drained the carb it may have gotten water after all your work. Dump or seriously filter the fuel.

 

[Jon67]

I agree with Larry M. take apart all electrical connectors and flush with WD40 and or contact cleaner. This includes spark plug caps. Check tank for water. Also check leg oil. And a new fuel filter. possibly change the oil again.

 

[High Wire]

Any final update on this event?

 

[dwpsco]

Any final update on this event?

Aye, changed oil twice, then ran her hwrd for two days. First day she was fitful, second ran pretty good. Running normal since

 

[dwpsco]

Oh and the oil light never worked again. I check the oil evey time i take her out

 

[psneeld]

Don't give up. Plenty of outboards survive sinking just fine. As a former salvor saw it all the time.

Even usually the parts that may be affected won't cost as much as a new engine...as long as the sunk engine had some post sinking preventative maintenance done quickly.

Can't speak for Hondas, buy my Yammies had all the electrical connectors so well sealed plus I can only guess filled with silicone grease that NO water ever entered them after sinking ( no more than 6-7 feet, can't say for deeper).