Logo
FULL SITE MENU

Honda bf135 - was submerged and trying to make it work again. ECM dead?

J

JRSbuilt

New member
To whom?
I recently bought a boat and motor from a buddie that sank salt water for about 12hrs.
My current issue is with getting the Honda BF135 outboard motor to work again.
My Mechanic and I drained all fluids and replaced with new for now until I can run it some more and then change again thereafter.
All obvious water has been removed. Fuel system has been flushed with main filter removed until it fires as. Two spark plug coils were replaced as well.
It will turn over but failed to run. I contacted dealer but he will not hook up the ECM as it may ruin his laptop/software. When the ignition key is turned but not on all the way the fuel pump only gets 12volt power for about 1 second. Dealer says should be about 7-10seconds to prime the system. So I need to figure if the harness is the issue (wire(s)) or the ECM.
Does anyone know of a reasonable test for the ECM (main computer) that can determine if it is dead or alive?
thanks for a response.
 
I assume you have already disconnected each connector on the motor and cleaned and lubricated. It does not take long for corrosion to develop. I also hope that you removed all the water and changed oil and lubricated the cylinders right away. If it sat after it came out of the water, it is going to be a steep uphill struggle.

Hopefully, you disconnected any power going to the motor as soon as you could.

Make sure all of the water was removed from the flywheel area (under the starter). You should also lubricate inside the area. Once the crankshaft starts corroding or some of the plugs under the powerhead corrode, oil will start leaking.

I hope that multiple oil changes will clean out the timing chain area, which is totally encased on the top of the engine.

Make sure that the ECM is totally dry before you ever apply power to the engine. It may be too late. But maybe not.

Remove the ECM and put it in front of a fan with a little heat (not a lot). If you are in a warm climate, just a fan will do. You should let it sit that way for a few days.

Keep in mind all of your cables have wicked salt water, so it is only a matter of time before you have issues there.

Your key switch is especially compromised. Even though they are "sealed" the trim switches, trim relays, main relays may also have issues....maybe not now, but possibly in the future. They are sealed to resist splashes not to be "under" water.
The maps, throttle position sensor,and IAC probably have some issues. I have not even mentioned the starter and alternator will have issues.

OK....all that being said...when you turn the key switch to on, do the warning lights come on for about two seconds and the audible alert sound? Not to disagree with the dealer, but the pump runs for about two seconds as the lights are coming on and audible in sounding.

I assume that you have already cranked the engine without spark plugs, to lubricate the cylinders and remove any remaining water.

To answer your question....There is no good test, that I know of, except to put the ECM on another engine (once it is thoroughly dried and cleaned)

Once you can crank it, you could use a spark checker and at least check for spark.

Mike
 
Even IF, and it is a pretty large IF I would say...IF you could get the current ECM to work I don't think it will work for long. If you go offshore or into secluded waters with this outboard, relying on that ECM is nothing more than a crapshoot at best. The water has gotten in the box will have left behind deposits on the circuit boards even if you have completely displaced the moisture. The deposits working away on components and board traces will undoubtedly cause an open or an internal short in time and she will leave you flat when it happens. I would not and could not trust it.
 
Thank you for the above reply Hondadude. Some of the suggestions have been done prior to your message others now in progress. The engine however was tried with Ecu in place and not in a few day dry out as suggested. The limited results from attempting to start as follows:
- spark was getting to the ignition coils but two tested as bad. They were replaced with new ones.
- compression check of cylinders results were 2 at about 120 psi, and 2 at about 100psi. The dealer mechanic said ok to the results.
appears to a fuel pump issue
- fuel system lines were blown out and filters removed so any remaining water particles may pass through.
- fuel pump tests for power for about 1 second but shuts off. Dealer mechanic says should be on for 7-10 sec...
- fuel float area was removed and cleaned as well a small amount of corrosion was observed and cleaned before reset.
- It has been suggested to me to replace the fuel pump.
? Is there a good test for the fuel pump both in position and out of the motor?
 
My book says compression should be between 179 and 256 psi. Should be checked with throttle wide open.

As for the fuel pump test. You should be able to get fuel pressure of about 40 to 47 psi. I do not know of a specific test when the pump is out of the system. Past experience has shown me, that once a high pressure pump gets water in it, it too will eventually fail.

It sounds like we all are giving you just an abundance of good news!

Mike
 
In response, I know it's an uphill battle to get it to work again and be dependable in the long run. For me it's fun to work on it and learn as I go. I'm in the trench right now and think with only 180 hrs on the engine and only a 2011year it's worth the trouble and even if I'm into it for 2k. My dad has said before "only the mediocre are always at their best". He is 86 now. I believe in god and has a plan for us all and I said prayers for this process. Thank you for your assistance in this matter.
Please give some detail to below:
I have only tried the compression test once and with the throttle in neutral as the engine won't fire up yet so it would seem to me the position of the throttle won't matter. Perhaps you may expand on why, when to try it again and how to do it in order see the heart condition of this patient.

JR
 
It has always made a difference for me. Put the shifter in throttle only and then go to full throttle.

Make sure all the spark plugs are removed and your battery is fresh.

Opening the throttle, opens the throttle plate in the throttle body and will allow the engine to get more air.

I think you will find it makes a difference.

Mike
 
Hello again. I have tried to turn the engine over to check compression with an open throttle but one of the fuses 30 amp keeps blowing soon after a try. So the result of compression can't be measured at this time.
I tried to unplug the ECM still shorted. I next disconnected the alternator and still blew a fuse. So now I have removed the starter to have it bench tested next week.
Am I on the right course or are there some other tests to see what may be causing the short?
Thanks for your assistance.
One last thought was the key start panel could n
be an issue if tied to other things in the boat that are not correct. The short happens only when the key is turned to the start position.
 
If the fuse would blow when you turned the key switch to on, then other things connected to the switch (eg gauges, etc) could be causing the problem. Turning the key to start, directs us to the cranking circuit.

Remove the white/black lead from the starter and test again. If it blows the fuse, then most likely you have a bad (internally shorted) main relay. It contains the relay to power the ECM and everything else and the starter relay. Corrosion has probably built up inside and when the start relay is activated, the power on the contacts gets shorted to ground through the corrosion.

You can crank the engine, by putting 12v to the starter terminal where you removed the white/black lead.
If the starter does not crank, then you may have a problem with the starter.

If you are taking the starter to get tested, you should have them take it apart and clean it to remove the effects of the saltwater.

Mike
 
Thank you Mike,
if the main relay is internally shorted, can this be cleaned or am I looking at a module replacement?
If so is there a service Manuel download that would help me diagram the parts and have numbers related to them as well to aid me?


JR
 
The main relay is a "sealed united". I say "sealed" since they have had trouble in the past allowing moisture in them.

The is no downloadable manual that I know of other than the owner's manual. Pick your manual by serial number and download for free. http://marine.honda.com/owners/manuals/models/BF135

The wiring diagram is one of the last pages in the manual. There are some manuals that did not have the diagram...so if that is the case with yours.....pick an earlier serial number range and download one of those.

I would highly recommend buying the official shop manual from Honda. You can get it from their ebay store or
Amazon store. http://marine.honda.com/owners/manuals/shop-manuals

One place to find parts and what they look like, before you get the manual is boats.net http://www.boats.net/parts/search/Honda/Outboard Engine/parts.html

Mike
 
Update. I removed the starter to have it checked and the alternator as well and we found both needed to be replaced.
after doing so the engine would turn over, but no fuel to the fuel injectors. So I took the fuel pump out and bench tested. The fuel pump chamber needed to be cleaned. We then tested it and it had a good flow. Put it back and the engine fired up! So now we have an engine that sort of works.
The pressure test at open throttle will soon happen and I will share the results.
Is there a recommendation for a external fuel filter and water separator that would be recommended?
i saw a few bit did not know what micron level would be best for the Honda bf135 outboard.
let me know if you could.
thanks
 
Racor 10 micron. I like the ones with the clear bowl on the bottom so that you can easily drain them and easily change the filter element.
 
Update,
Thanks for the reference Chawk and advise from Mike.
The engine has life now again but not yet put in the water for a test.

I am now in need to change the impeller as it seems that it's about time with 200 hours on the motor.
? What impeller kit for a 2011 BF135 would be recommended?
Also, are there any other systems suggested to test or replace before a 'boat in the water test' after the engine has been submerged in salt water? IE valve adjust now or after run in the water...
Any helpful ideas are appreciated.

JR
 
I would replace the entire waterpump. That way you are sure that you are starting out fresh. 06193-ZY6-A01 http://marine.honda.com/outboards/accessories/water-pump-service


While you are there, it would be a good time to check valve clearances. Going under water should not have effected that, but it is time to do it.

If the key switch and trim switches went under water, they will be failing soon.

Signs of the key switch problem would be either engine not starting or possibly even cranking on its own due to the corrosion.

As for the trim switches, sometimes the trim will not work, but more often the motor will come up or go down on its own.

I still expect the main relay to fail at some point.

I am surprised that the map sensor is not shot. Even if it goes, the engine may sound an alarm but it will run.

If you have only changed the oil one time, you will have to do it again within 15 - 30 minutes of running at temperature....and maybe several more times.

In a previous post, I have already made recommendations on things to change/check/clean...although probably not an all inclusive list.

In any case, do not go far from shore for a while before you are sure everything works ok.

Mike
 
Well,
I ran the Honda BF135 motor in the water and now hear an audible alarm when in neutral.
When the motor is in forward or reverse the alarm goes quiet until Neutral is selected.
Some months ago in the previous thread Mike aka Hondadude said the map sensor may fail.
Does this sound like that or something else?
Thanks for your assistance in this matter.

JR
 
Back
Top