EMM Failures - Why??

[Jeanne]

Our 2nd one just went out on our 2005 75 HP Etec. Not happy...

[Jeanne]

Our 2nd one just failed on our 2005 75 HP Etec. Not happy... of course it occurs when we are out on the gulf or intercoastal waters - miles from the launch - cruising along & all of a sudden Nothing! ☹️

[BluewaterBill]

We are very sorry to hear of your engine situation. Failing EMMs is not a common occurrence. Often there are other causes for the multiple malfunctions such as overheating, loose or corroded connections, bad battery, reverse polarity, etc. It is recommended that you have an authorized Evinrude dealer check over and determine the reason for the 2nd failure and to call dealer support to see if any consideration could be extended to you.

You may also email the engine serial number, your contact information, and your dealer to  brp.care@brp.com .  They cannot do anything until it has been examined by a trained technician.

[daveb1]

I have just expeienced my second EMM failure on one of my 2014 E90s.

No overheat codes.

Reports an Open circuit injector. On testing, the injector was open circuit, however no joy after replacing the injector as the EMM had also failed.

Required replacing both the EMM and the injector to resolve.

This has now happened twice and no other independant cause can be found that may have contributed to the failures.

I am a qualified electronics engineer with 25+ years experience.

If designed properly, an EMM should not have to rely on water cooling. 

Likewise an EMM should contain protection for pretty much any surge, over current, short circuit or polarity fault thrown at them.

Basically, they should be pretty much bullet proof.

It is a pity that these EMMs seem simply not to be up to the task.

[BluewaterBill]

We are sorry to hear about your EMM issues. The EMM has been around since the turn of the century in various configurations for several different engine platforms over the years. As will all larger outboards with large capacity charging systems built into the engine, their regulators and rectifiers employ water cooling to dissipate the generated heat. 

An EMM does contain the regulator and rectifiers for the E-TEC high output alternator and also switches the windings under the flywheel back and forth from series to parallel, depending on the engine rpm and output needed. Those are in addition to the sensor circuits, various voltage regulators, and the onboard computing components.  As you know, heat, voltage spikes, corrosion, and vibration are the main enemies of electronic components. All those conditions are found on outboard motors and with the proper rigging of the motor, not running with damaged props, and not using battery wing-nuts contribute to reliability. The Evinrude E-TEC EMM internal structure is rugged and the electronics are encapsulated. Here is a link to an article about the basic operation of an EMM.

http://www.evinrudenation.com/owner-zone/emm-unwrapped/

[mlee76]

Sorry bluewater bill but I have to disagree with you. The internals of the etec emm are not rugged at all. Yes heat and voltage spikes and corrosion are the enemy of electronics, but as you know, no other outboard manufacturer seems to be having the failure rate of emm's like the etecs. I have two 2011 90hp etecs and I am currently negotiating the replacement of a 5th emm. This one lasted 30hrs before it to stopped charging the battery. I know you will talk about wing nuts and so on but I have gone to great lengths to ensure all is right in that department. They are poorly designed and unreliable. One etec mechanic described them to me as being like light bulbs. Some go for ever and some burn out for no apparent reason. I ran two other brands of outboard for over 30 years combined, put nowhere near the attention to correct cabling and babying the electricals like I do with these etecs and I never once had an electrical issue with either motor. Unfortunately I'm stuck with these motors as to replace them is out of my budget. I sincerely hope brp engineers go back to the drawing board and redesign a replacement emm for the I2 and I3 etecs that is as Daveb1 puts it, bulletproof.

[BluewaterBill]

Now may be a good time to remove and clean all the ground wires on the motor. Another item to check is the large blue capacitor. Pull the rubber boot and inspect the connections for corrosion or looseness, look for any oil film or leakage from the canister, and shake it to see if anything is clunking or rattling inside.

Can you post a recent engine report so we can see the history of the motor?

[mlee76]

would love to post a report but can't work out how to attach it.

[mlee76]

I have put images of the engine report in my gallery. I hope it can be viewed by all.

[mlee76]

Checked all ground wires and capacitor. All looks fine. Can't see that these could be the cause of constantly failing EMMs on this motor. My problem is te 12v Battery charging stops working. The EMM is making 14.3v internally as seen by the diagnostics. It just doesnt extit the EMM to appear on the external charge wire. My understanding is  (I am happy to be corrected on this) that the capacitor provides smoothing for the 55v side of the circuit and therefore is unlikely to have this effect on charge failure.