Bass Fishing Forum

General Bass Boat Discussion => Outboard Motors => Topic started by: lewis_is_bassin on March 16, 2019, 06:16:15 PM

Title: Mercury EFI continuous alarm, help.
Post by: lewis_is_bassin on March 16, 2019, 06:16:15 PM
I have a 1998 Ranger boat with a 150 Mercury EFI, 2 stoke.  The issue  Iím experiencing  is a continuous alarm. A few weeks back I ran low on oil, in the big tank. The small reservoir never went empty. As a matter a fact it was full when the alarm came on.

Since I was just about done fishing for the day, I figured I might as well call it quits and made a 3-4 minute run(half throttle) back to the ramp. Since then, every time I start the outboard I get a continuous alarm. 

Iíve added oil, replaced the water pump, spark plugs, thermostats and checked for any blockage (there was none). Iíve also tested the heat and oil sensors by disconnecting them and staring the outboard for about a minute. Still no luck. The boat runs fine, lots of power just that darn alarm. Any thought on what could be causing it to go off? :-\
Title: Re: Mercury EFI continuous alarm, help.
Post by: Princeton_Man on March 16, 2019, 06:21:40 PM
The float sensor in the big oil reservoir is most likely stuck.
Could be air in the line too.
Title: Re: Mercury EFI continuous alarm, help.
Post by: BarryFL on March 16, 2019, 07:36:33 PM
Low oil in engine reservoir or water in fuel will be a four beep alarm every two minutes. A continuous alarm is usually temperature related. If you have full power it isn't going into guardian mode. At least that's the way my 2001 225 EFI is.

You did say continuous alarm, right?

~Barry~

Title: Re: Mercury EFI continuous alarm, help.
Post by: lewis_is_bassin on March 16, 2019, 09:55:48 PM
Hey guys thanks for the quick replies. Correct, Iím getting the constant alarm when I crank her over. Initially I thought it was heat related and i supposed it very well could be, but whatís throwing me off is even on a cold start I get the alarm.
Title: Re: Mercury EFI continuous alarm, help.
Post by: BarryFL on March 17, 2019, 08:48:58 AM
I've got the service manual. I'll see what it says and report back.

~Barry~

Title: Re: Mercury EFI continuous alarm, help.
Post by: BarryFL on March 17, 2019, 11:11:40 AM
The repair manual says it's either a bad overheat sensor or bad ECM. The way to test is to disconnect the sensor and turn the key to the on position. DON'T START. If the continuous alarm still sounds, its a bad ECM. If no alarm, bad overheat sensor.

~Barry~

Title: Re: Mercury EFI continuous alarm, help.
Post by: lewis_is_bassin on March 17, 2019, 12:54:24 PM
Barry, thanks man! I appreciate your help. I'll try these options and report back.
Title: Re: Mercury EFI continuous alarm, help.
Post by: BarryFL on March 17, 2019, 02:17:53 PM
Just FYI, most bad sensor alarms will sound without the motor actually being cranked with it in the on position.

~Barry~

Title: Re: Mercury EFI continuous alarm, help.
Post by: lewis_is_bassin on April 01, 2019, 08:43:30 PM
An update: After some time of troubleshooting, I wasnít able to figure out the issue, so I took it into an authorized Mercury dealer. They figured out the issue. I have an aftermarket oil injection system that came with the boat when I bought it(Marine solutions EOI system). It appears when I ran low on oil, the pump was damaged. I was quoted $1500 to rebuild the system using mercury parts or disable the system and premix the oil with my fuel, which would be very inexpensive.I would like to fix the issue the right way, does $1500 sound reasonable?
Title: Re: Mercury EFI continuous alarm, help.
Post by: D.W. Verts on April 01, 2019, 11:23:21 PM
I'll ask my tech...