BajaNomad

Mercury Blues!!

bajabass - 10-23-2011 at 07:48 AM

Does anyone near or in La Paz know a good Mercury Outboard mechanic??? I'm having an alarm issue I cannot easily sort out. Been to one, unnamed shop 3 times, water trials, new t-stat and impellar, bigger prop, run the scanner, same issues. Motor runs great, smooth, low hours. Just the darn alarm if you even try and run over 4,000 RPM. :(

Pescador - 10-23-2011 at 07:58 AM

First of all, I suspect it is your oil sending unit but it could also be the temp sender, both of which will sound an alarm.

There was a really great Merc mechanic who moved out of La Paz Marina and opened his own shop up. I think it was on like 16th of Sept. or maybe a little further east and about 10 blocks south of the malecon.

This may be an old lead:

Mercury, Carlos Murillo, Constitucion y G. Farias
122 9033


[Edited on 10-23-2011 by Pescador]

bajabass - 10-23-2011 at 08:15 AM

Thanks Jim. I put a "known good' coolant sensor in, same exact issue. I'm running to California next week, and may just pull the motor off the boat and haul it north. I'll try and contact your guy on Monday. Could just pick up a couple new sensors and pray alot!! The only codes in the computer are for over rev, but WAY in the past. Based on that, the mech said install larger prop to cut RPM. Boat runs even better than before, planes faster, better mid range throttle response, and cut my 20-24 mph cruise RPM from 4,800 to 4000 RPM. Until the alarm triggers:fire:

bajabass - 10-23-2011 at 08:37 AM

Just tried the number Pescador, no go. Thanks though. Any more leads out there???

Google is your friend

bajaguy - 10-23-2011 at 08:48 AM

Search Google for "Mercury Outboard Alarms" and see what you get.

Diver - 10-23-2011 at 08:54 AM

Have you tried Hector ?
His shop is at the corner of Abasolo and Miguel de Legaspy, near the marina and next to a boat supply store.
He has fixed many motors for me over the years.
He is college-educated and speaks good english with a heavy accent.

Russ - 10-23-2011 at 09:05 AM

If you take it across the boarder without the boat they'll get you on duty when you return. Just something to consider...
or try this http://www.thenextbite.com/node/2407

Jack Swords - 10-23-2011 at 09:15 AM

Was that Carlos of "Waterworks" that moved out of the marina?

Diver - 10-23-2011 at 10:12 AM

From the above website:

Re: mercury optimax overspeed alarm at 4000
For anybody else in the future experiencing this overspeed alarm at 4000rpm

I have two 2006/2008 Optimax 90's on a 6.5m Delta RIB, and was given this overspeed alarm a few weeks ago. It would come and go and was inconsistent but slowly got worse and worse.

I had gone through a series of troubleshooting ideas. Fuel flow, water pressure, but ended on the Neutral Switch Sensor, which is located around the starboard side of the engine leading underneath the 2stroke oil tank. It is nearly impossible to access it without taking off the lower unit cowling, and lifting the oil tank up. This switch tells the computer that it is in gear, or else it will limit your revs whilst in neutral, without this functioning switch, there is no analog way to bypass it and achieve full power.

I fortunately have a spare engine which I was able to switch out this Neutral switch sensor and problem was solved immediately. It is a tiny black box, with two black cables, and a grey pin which when suppressed, tells the engine that it is in gear, allowing it to pass 4000rpms.
Now hoping Mercury will stand by their warranty and send me a replacement so i can have a spare, just in case.
In retrospect, it seems entirely trivial to have this sensor. Note: optimax are also equipped with a TPS- Transmission position sensor which ALSO tells the engine when it is in gear. If you disconnect this cable, you can start your engine but will not have any response if you attempt to put it into gear. What is the point of having both of these sensors? There are too many sensors on modern engines. If you dont own a diagnostic computer, or perhaps a spare engine, there is almost no way of troubleshooting or eliminating options if there is a fault in a sensor.

Cypress - 10-23-2011 at 12:18 PM

Why the heck do they add all these "sensors"? Sensors? Hell, if the motor isn't running right I don't need a sensor to tell me. It's got to be fuel, temp. or the lower unit.:?: Now we need to wonder if the "sensor" is malfunctioning.

bajabass - 10-23-2011 at 01:01 PM

Diver, this is a 60 HP 4-Stroke EFI motor. I have no idea if the 2 stroke Optimax uses the same sensors. I'll pull the side cowling a look around.

Bob and Susan - 10-23-2011 at 01:51 PM

remember if you take it north...

a boat motor without a boat is harder to cross than a boat with a motor attached....:light:

bajabass - 10-23-2011 at 02:51 PM

Yeah, I really don't want to haul it, or the boat and motor north or south again. :(

Barry A. - 10-23-2011 at 03:02 PM

Quote:
Originally posted by Cypress
Why the heck do they add all these "sensors"? Sensors? Hell, if the motor isn't running right I don't need a sensor to tell me. It's got to be fuel, temp. or the lower unit.:?: Now we need to wonder if the "sensor" is malfunctioning.


------you just identified why I LOVE my 1964 Johnson, and my 1978 Johnson------------NO SENSORS, and other do-dads that make decisions for me, and block what I want my motor to do--------drives me nuts on these newer motors. Both my old motors are a cinch to keep running right, and have adjustments in plain sight that even a squirrel could figure out. Even my 1988 Mercury makes too many decisions for me, has no obvious 'adjustment knobs' and I can never find what is wrong with THAT motor. It has idl'ed rough, and always died at idle speed even at 800 rpm's, all it's life and NOBODY can figure out why, so far, let alone ME.

I am beginning to think that IFlyFish is right, and the "corporations" are out to bamboozle us so that we CAN'T fix anything any more.

Drives me nuts!!!! :fire:

Barry

Cypress - 10-24-2011 at 12:16 PM

Mercury outboards have always been faster, more fuel efficient and lighter than Johnsons or Evinrudes. The throw-out clutch was better than the shear-pin. However, I'd take a Johnson or Evinrude any day over a Mercury. The reason? If you have problems with a Mercury, you've got a big problem. Johnsons and Evinrudes? You might just be able to fix 'em yourself.:yes:

bajabass - 10-24-2011 at 03:38 PM

Thanks Pescador! I'm headed to California Friday, I'll talk to a couple dealers, buy a couple sensors, sacrifice a virgin or two, and maybe I will get lucky.:rolleyes: This motor is immaculate and low hours, has been GREAT until this. Probably a simple problem, but communication at the shop here is tough!!