Submerged BF115

Hello! I hate to have to be here, but I know from previous experiences, this it THE place to go for expert help.
I have twin 115's on my center console which unfortunately found themselves at the bottom of the bayou I live on.
I've worked on submerged engines before (I'm a certified A&P license holder for aircraft and have worked on cars and boats all 54 years of my life).
One engine I have working perfectly. The other engine is what concerns me.
As soon as I turn the key on, a steady alarm starts and will not go off. I'm getting all my lights coming on and staying on.
The engine actually starts and idles well, but I'm concerned about running the engines to complete the oil changes necessary to flush the inside of the engines.
What would cause a steady alarm even when the engine is running and is it safe to run the engine with it sounding?
Thanks for any help you can give me.
Jim

You did not say what year the 115 was. There are two different models, although the alarm systems are similar.

How long did you let the ECM's dry out before you put power to them? I assume all connectors were pulled apart cleaned and dried....

The lights are coming on because there is a ground on a lead going to each light. So the ground is coming from somewhere. It normally comes from the ECM. One quick way to eliminate the ECM as a problem is to switch the ECMs and see what happens.

So the grounds could also come from any one of many connectors, from water inside the motor's wiring harness or the wiring harness going to the helm. As you probably know, when the boat goes down, the wiring harnesses act like wicks and really soak up the water.

Is it safe to run? It is hard to tell. Try switching the ECM's. You might even run the wiring harness of the other engine from the helm to the faulty one (hopefully, the faulty one is the Starboard...so the harness will reach).
I would probably go ahead and run it to get the water out, watching temperature, etc.. Just do not run it hard. Then you can take your time fixing the rest.

Don't forget to remove the starter and suck the water out of the flywheel cavity and try to dry it out.....I have used the blower end of a shop vac with small hose adapted to stick inside to get it dry. I have also sprayed WD-40 or Motorkote to help displace some of the water and lubricate the surfaces inside. I connected two or three of the straws with shrink tubing to access the corners. The "official" way to clean out this area is to remove the powerhead.

Good luck.

Mike

They are 2012 model engines. Yes, the good running engine is the port engine, the one that alarms is starboard. This may sound like a stupid question, and I think I know where it is, but where's the ECM? Is it the black box just forward of where the 3 wires come in to the main power box (fuses)?

The ECM is on the starboard side toward the front of the engine. There should be about a 1" cable assembly coming down to it from the upper part of the motor.

I am assuming that you know that even though these are "sealed" units, they were not sealed for underwater operation....and can take on water. Likewise, the starter may be "sealed" but I will bet there is water inside that. Unless you disassemble, clean and lubricate, it will fail (maybe not today or tomorrow, but probably within a year).

As long as power is applied to any component that is wet, corrosion will build....it is only a matter of time unless all is cleaned, dried and lubed. I am adding that especially for any others who may be reading this.


Mike

Yeah, after reading the other threads, I can tell I need to disassemble everything and do some intense cleaning/lubing. Do you have any recommended lubricant for things like starter and alternator bearings?

Yeah, after reading the other threads, I can tell I need to disassemble everything and do some intense cleaning/lubing. Do you have any recommended lubricant for things like starter and alternator bearings?

Also, where can I get a manual for this engine? Online I cannot find anything newer than 2008 models.

Manuals are generally available through Honda's Ebay and Amazon stores. They are presently closed until after the first of the year. You should only by the official Honda Manual, based on your serial number.

As for lubricant for the starter and alternator...maybe Jimmy D will jump in with some suggestions. We usually pull them off and have a local starter/alternator shop go through them. If the engine has a lot of time on it, we just put a new starter and alternator on it. Most of the boats that we get that go down are work boats that the customers need to get back into service right away....so timeliness is important.

Mike

Ok, thanks. With just about 100 hours on my engines and no dire need for them until the weather gets a little warmer, I can take the time to do things right. I did get a good jump on one engine last night after work. I've done most of the connectors and boxes on the right side of the engine. I'm down to pulling the starter then I'll jump on the alternator. Are there any references you know of online for their removals? The starter seems to be straightforward, but I haven't started with taking the shrouds or anything off the top end above the alt. Just my luck that the ebay store would be closed when I need it most! Jim

The alternator is not hard to remove. You will have to remove the top cover and move some hoses out of the way to do it. Just take a lot of pictures as you take things apart so you know how the hoses, cables, and belt go as you put it back.

Pay close attention to the belt tension when you put it back on. The specs are in the book. The belt should be pretty darn tight. 88 -110 lbft using belt tension gauge.

Mike

Thanks dude. I do love the ease of taking pics pre/post these days since the digital cam in the phone. Makes it a lot easier when you're scratching your head thinking "did this go on first or did that?"
I don't have an "official" tension gauge, but I do have a calibrated arm. You're right, 88 - 110 lbft is pretty darn tight. Fortunately, that's a large enough range that even tho my arm hasn't been calibrated lately, I should be able to get it within the range.
I took the starter off the good engine today, and as y'all had told me, there was water down under it on the flywheel. I guess I know what I'll be doing on the 1st! Glad I have a good shop vac! Starter was in EXCELLENT shape. No sign of water at all. A little corrosion on the contact of the solenoid, but that's to be expected. I live in a salt-water environment even tho my bayou is brackish. It had been raining the day I sunk, so salinity was down extremely low.
I do appreciate all the excellent info I get on this forum.
Jim