three beeps from Merc 50 hp 4 stroke

[RSH8]

Just got back from Minnitaki near Sioux Lookout, where the walleye fishin was great. We had problems with our 50 hp Merc 4 stroke EFI, 2004. After a run for 15 minutes and about 3 hours of trolling, the engine sent out three loud beeps. So we headed back to camp, and the engine would beep 3 times every few minutes. After about 10 minutes of running full speed, all the gauges and fish finder started dying, and shortly the enige itself went off and would not turn over. Then we put in a different, charged battery, the engine started right up, and we got back OK. We would then recharge the original battery and do the whole thing over again.

Sounds like the engine is not charging the battery. It has been suggested that I need to replace the voltage regulator. I think the battery is OK, it is a deep cycle, the cells all have water, and it recharges to the expected voltage, 13.2 volts. I don't understand why the engine would die out while running even if the battery is dead. Otherwise the motor has been super, starts right up every time.

Any advice would be appreciated.

[Unlogged NC]

This happend to my '03 60HP Merc 4-stroke a number of times. They can't figure out what is going on. First they worked on it a full day w/ no luck. Next time it happened they said the rectifier fuse had blown. Replaced it and it worked great. Did the exact same thing to me 2 weeks ago. Again no answer from the marina. I am seriously thinking of hooking up an onboard charger and plugging in each night to be sure I have a full charge. Either way it is getting very irritating as I do not feel comfortable going in distance w/ this rig. If you find an answer, please post as this has happened to a number of us.

Good luck,

[Jimmy Jig]

Three beeps every 4 mins. is "Engine Fault" take to dealer.

[RSH8]

Three beeps every 4 mins. is "Engine Fault" take to dealer.

Right, it is at a repair shop now. It will take them a while, will post what happens.

[brentfrank]

I had to replace my voltage regulator and water pump last year due to the same problem on my Mercury 2004 60hp 4 stroke. Water pump was weak and didn't pump enough water to cool the voltage regulator, the dealer told me it was water cooled also. Pumped enough for the motor but not the regulator. thats what the dealer told me anyway and haven't had any problems since.

[yarcraft91]

I had to replace my voltage regulator and water pump last year due to the same problem on my Mercury 2004 60hp 4 stroke. Water pump was weak and didn't pump enough water to cool the voltage regulator, the dealer told me it was water cooled also. Pumped enough for the motor but not the regulator. thats what the dealer told me anyway and haven't had any problems since.

Interesting- IIRC, Mercury says to replace the impeller on that motor every 3 years. Maybe that's why. You have to wonder how the water pump could be too weak to cool the regulator, but still cool the motor OK, since the motor creates far more heat than the regulator. It may have something to do with where the regulator is mounted.

[Unlogged NC]

Forgive me as this is over my head, but are there "checks" a dealer can run to see if this is a problem or is this something we must replace and see what happens? The reason I ask is my dealer said everything checked out and they can't find the problem. Not blaming the dealer, just trying to get a handle on how this stuff is diagnosed. So if it is the water pump and volatage regulator, this could/would cause the battery to go dead seemingly out of nowhere? Is this because it is not receiving any charge while the motor is running?

If someone could please explain a little more I would be greatful. Hoping to get this issue resolved and behind me ASAP. Also, just curiuos about the cost of replacing the water pump and voltage regulator. Looking for ballpark, certainly don't need specifics.

Thanks again!

[brentfrank]

If I remember right it was just under $500.00 last June to have this done. The voltage regulator is mounted on the right side of motor if you are looking at it from the back. Mine was melted. I'm not at all mechanical and just put faith in my mechanics. They said I was very lucky not to have a fire. My motor had 4 hard seasons on it as I also use the boat for duck hunting and had pushed ALOT of sand through the system. I guess Merc 60hp aren't supposed to be used as mud motors lol. Now I will just have things replaced every couple of years.

[yarcraft91]

Forgive me as this is over my head, but are there "checks" a dealer can run to see if this is a problem or is this something we must replace and see what happens? The reason I ask is my dealer said everything checked out and they can't find the problem. Not blaming the dealer, just trying to get a handle on how this stuff is diagnosed. So if it is the water pump and volatage regulator, this could/would cause the battery to go dead seemingly out of nowhere? Is this because it is not receiving any charge while the motor is running?

If someone could please explain a little more I would be greatful. Hoping to get this issue resolved and behind me ASAP. Also, just curiuos about the cost of replacing the water pump and voltage regulator. Looking for ballpark, certainly don't need specifics.

Thanks again!

Voltage regulators can generate large amounts of heat. The voltage regulators in medium-large outboards are water-cooled, unlike the air-cooled voltage regulators in automobiles. If the water pump isn't delivering enough water to keep the regulators cooled, they overheat, fail and one of two things can happen- the charging voltage becomes unregulated and therefore too high or you get no charging voltage at all. Fuel injected motors use a fair amount of electricity in the fuel management system. No charging voltage will eventually drain your starting battery below the voltage required to run or start your motor.

It is simple to diagnose a loss of charging voltage. If the motor is running above idle speed and the battery voltage isn't 13V or higher (ideally 14.4), the charging system has failed.

[MarkG]

Merc 50HP EFIs require a battery of sufficiant voltage to run the ECU and fuel injectors. There are "batteryless" EFI systems in the Merc 25-30HP motors,but anything bigger, need batteries to work. With a failed charging system,the EFI itself ran your battery down as you were running the motor,then as it fell below minumum voltage caused it to alarm then quit.

Get the charging system fixed, the other issues will disappear.

[RSH8]

Thanks very much for all these suggestions, especially the last two. I have been wondering how to check myself if the charging system is working, now I know! Very useful.

For future reference, what other problems could cause the three beeps?

[unlogged nc]

I imagine the same holds true for a 60HP Merc 4-stroke as a 50HP Merc?

[yarcraft91]

Yes. The 50 and 60 horse Merc 4-strokes are the same basic 1 liter engine.

[MarkG]

I imagine the same holds true for a 60HP Merc 4-stroke as a 50HP Merc?

If you are asking if the motor requires a charged battery to run,,that is correct.
I am pretty sure that right now,The only Batteryless EFI system Merc offers is on the 25 and 30HP ,because they are often used in manual start installations,in rigs with no batteries. Merc CLAIMS to be the 1st using it,but Nissan also has it, and Tohatsu has been using it since 2006.

How those work is that when you pull the starter rope,there is a small charged capacitor system that energizes and holds the EFI circuits,that will then run and continue to run the fuel management system once the engine starts. It will usually take 2 pulls,at least if off a while,one to charge the system,one to start. I believe they can get away with batteryless on the smaller motors because the current demands are minimal. But on anything much larger It seems they still need the wattage capability of a battery to run bigger and more injectors,and more complicated ECUs and monitoring systems.

I am not sure how you would ever get any of these larger (40HP and up) EFI motors to run from a pull start in an emergency and keep it running with a dead battery,unless there is still some circuitry similar to what is on the batteryless system,at least to get it started. My guess is that it would still require the charging system to be operative to run the motor. With both a dead battery and an inoperative charging system,you are pretty much SOL. Isn't technology wonderful???!!!!

The batteryless EFI ,is not new technology,I remember some of the 1st EFI snowmobiles were Arctic Cats with the same type of pull start capacitor system in the late 1980s or early 90s.

[MarkG]

Thanks very much for all these suggestions, especially the last two. I have been wondering how to check myself if the charging system is working, now I know! Very useful.

For future reference, what other problems could cause the three beeps?

"3" beeps in itself is probably not significant other than it was not one "continuous" beeeeeeeeep which would indicate something fatal such as cooling or lubrication requiring the engine to be shut down immediately. With the battery voltage dropping below minimum and a failing electrical system,the ECU and systems monitors were probably just getting discombobulated before the whole thing shut down.

[unlogged NC]

Thanks for the explanation.

Here is what happened w/ my 60HP. Last year it ran fine, then all of a sudden no power in the morning. Dealer checked "everything" and couldn't figure it out. I would put a charge on it and we were go to go for 3 days. Then dead. Even replaced the battery. Still same problem. When I stored the boat for a month between uses w/out the key in the ignition, I would return and find the battery dead so something was drawing on it while in storage. Finally at the end of the year I was told I had blown a fuse in the rectifier which stopped it from charging. Never used it after that last year.

This year I opened the cabin and hooked everything up and after a month I still had a good battery so evidently the draw was gone. Ran the boat Thursday-Monday w/out problems. Monday night I changed the prop and ran it and the motor beeped. Can't tell you how many times but I know the upper end of my RPM's was too high so that is what I figured. I woke up on Tuesday and didn't have enough juice to start the motor. Had enough to tilt/trim (which was more than last year). Took it to the dealer who checked the fuse and said it was okay. Didn't really have an answer for me. So here I am now.

Could the charging system be screwed up and blowing the fuse was the warning? What would you guys do?

Thanks!

[RSH8]

If you are asking if the motor requires a charged battery to run,,that is correct.
I am pretty sure that right now,The only Batteryless EFI system Merc offers is on the 25 and 30HP ,because they are often used in manual start installations,in rigs with no batteries. Merc CLAIMS to be the 1st using it,but Nissan also has it, and Tohatsu has been using it since 2006.

How those work is that when you pull the starter rope,there is a small charged capacitor system that energizes and holds the EFI circuits,that will then run and continue to run the fuel management system once the engine starts. It will usually take 2 pulls,at least if off a while,one to charge the system,one to start. I believe they can get away with batteryless on the smaller motors because the current demands are minimal. But on anything much larger It seems they still need the wattage capability of a battery to run bigger and more injectors,and more complicated ECUs and monitoring systems.

I am not sure how you would ever get any of these larger (40HP and up) EFI motors to run from a pull start in an emergency and keep it running with a dead battery,unless there is still some circuitry similar to what is on the batteryless system,at least to get it started. My guess is that it would still require the charging system to be operative to run the motor. With both a dead battery and an inoperative charging system,you are pretty much SOL. Isn't technology wonderful???!!!!

"RSH8 adds:
One time when this happened we started the Merc using jumper cables from our trolling motor battery. It cranked right up and ran OK for the 15 min trip back to camp. I don't recall whether we got the three beeps or not during this run, i think we did get them.

I suspect that the battery on this run was not totally down, so there may have been enough voltage from it to keep the engine running this time. On the other two times, i think we ran the battery further down, then just changed batteries, this was much easier than crawling around in the compartment for the trolling motor batteries."

So what you say about there needing to be some volatge from the battery before the enigine will run at all makes sense.



The batteryless EFI ,is not new technology,I remember some of the 1st EFI snowmobiles were Arctic Cats with the same type of pull start capacitor system in the late 1980s or early 90s.


See above comment inserted into text.
It is copied here in case it does not make it.

"RSH8 adds:
One time when this happened we started the Merc using jumper cables from our trolling motor battery. It cranked right up and ran OK for the 15 min trip back to camp. I don't recall whether we got the three beeps or not during this run, i think we did get them.

I suspect that the battery on this run was not totally down, so there may have been enough voltage from it to keep the engine running this time. On the other two times, i think we ran the battery further down, then just changed batteries, this was much easier than crawling around in the compartment for the trolling motor batteries."

So what you say about there needing to be some volatge from the battery before the enigine will run at all makes sense.

[Unlogged NC]

I'm going to bump this up and see if others have advice as it relates the other person's problem w/ the 90hp merc. I still haven't been able to get the 60hp fixed.

Thoughts or suggestions are very much appreciated.

Thanks!

[peter8]

If the mechanic hasn't done it yet, check the diode in the wires on the front of the motor. If I remember correct it is inline and inside a shrink wrap. Mine was blown because "I" touched the battery cables in reverse.... Expensive lesson learned !!