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Submerged 70ESL75E outboard motor (1975 Johnson 70) in freshwater

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magicboat

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My little ski boat got swamped by the wake of a ridiculously obnoxiously oversized boat for Lake Travis. My engine, a two stroke 70ESL75E outboard motor (1975 Johnson 70 hp), went under for about an hour. It was docked and not running at the time. Now, the solenoid contacts corroded and can't enough current to move the starter motor, so I am replacing the solenoid. The starter motor works ok evidenced by bypassing the solenoid. I removed the spark plugs and turned it over until no more water came out. I emptied the carb bowls. I am very optimistic I can get it back into good shape, but if anybody else has done this or has other tips for me, please let me know. It was in top shape and is a great motor, never letting me down.

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Jump on the job.----Get it running and dried out asap.-----Or seek help to do so immediately.----You risk internal rusting of precision parts.
 
Hi, welcome. How long has it been? If the solenoid contacts are "corroded" already, it has been more than 2 days. Water alone, in the solenoid will not normally cause symptoms like you mention. Immediate attention is required here, or your motor will need it's powerhead dismantled and inspected. Gasket sets are available here. If you waited too long....it may start, but likely will not last because of rust/pitting on bearings/surfaces.
 
Thanks to all about the urgency. We are actively working on it, and we'll see how it works out. :rolleyes:

I will retract what I speculated about the solenoid contacts since I've since learned that the solenoid is a sealed unit. It could be a coincidence when it failed. It is a 45 year old part after all. Maybe some water seeped in some how. But in either case a new part is on its way.

Is the motor capable of starting if the solenoid is removed and the key is in the on position? Essentially just connecting the positive terminal of the battery to the starter motor. I see sparks happening in the plugs, so I assume yes.
 
At bare minimum go buy about 3 cans of fogging oil if you can't get it running. With the spark plugs out bypass the solenoid and while someone cranks the engine spray fogging oil into each carb throat. Really get the engine soaked well until you see fogging oil spraying out each spark plug hole. This isn't a perfect solution, but it buys you a little time until you can get the electrical issues figured out and get the engine running on it's own.

KJ
 
You have to get this motor running ASAP !!!-----The solenoid does not need to be on there.------Get this motor started before it is too late.-----Corrosion marks are visible on submerged motor cranks / rods / bearings after 24 hours if they are not dried out !!!!
 
Thank you for the excellent useful advice about Stabil fogging oil, and I executed it. I also first flushed the system with extra fuel+oil mixture from the carbs then from the spark plug holes.

Thank you for describing the urgency of the situation again and I will attempt to start as soon as time permits, with or without solenoid and report back.
 
Some manuals indicate that motor must be started in 6 hrs after recovery or put it back ( resubmerge ) into the water.-----They can be under water for weeks.-----On recovery you need to act QUICKLY or learn through an empty wallet !
 
Right. Once exposed to oxygen, the trouble begins. Maybe that's why they call rust "oxidation". See this illustrated here with a steel nail.
 

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It is even worse in a motor with non similar metals.-----A perfect galvanic cell.----I am going to be blunt and say that some folks are not aware and slow to accept the fact that the motor will suffer within hours if water is on the bearings.
 
There is no doubt that in a perfect world we would have commenced recovery immediately.

Engine started, runs fine. We got the engine nice and hot. We will keep you posted in the coming months about its status. It will be interesting to see what damage actually occurs. Thanks to all.

My boat is leaking but we can't figure where. By the end of the day there are a couple of gallons coming out the drain. Is there a forum anywhere to talk about that?
 
Damage did occur.----But not something that shows up in an hr.----Say 300 running hrs from now the motor goes boom.----Someone might say where did these corrosion marks on the crank and rods come from?----Do not have enough fingers and toes to count how many times I have seen this type of damage.
 
I am not stressed.----I try to share many years of experience to novice boat men.----Sometimes not understood or appreciated !
 
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