89' 340 Sea Ray systems monitor

[maestro7879]

Just looking for some clarification. I have an 89' 340 Sundancer with the systems monitor in place.
Does this unit only look for 12v from something and then trigger the LED ?

The unit I have is covered in red cement? so it's difficult to see what is going on. The unit itself has a ribbon cable coming out of it and then each wire is separated and screwed into a long strip with all of the devices that are monitored on it.

The issue that I have is that I can trigger the LED but the alarm won't sound. I have tested for voltage at the alarm and have nothing.

Is this circuit just simply looking for 12volts and turning on the corresponding LED and then supplying 12v to the alarm ? Just looking for clarification because if that's the case I could easily rebuild the whole unit.

I have tested with the bilge high water alarm (which is triggered and needs to be fixed). I have 12volts coming in from the labeled wire and that wire is jumped to the corresponding wire in the ribbon cable which also has 12volts. If I remove that wire the light will go out. This just seems to simple not to fix and upgrade.

The unit in my boat does not look like either of these - http://logicleveltech.com/searayboard.html

 

[Pyrojodge]

What you have looks like this?

The buzzer only buzzes on certain instances(low oil pressure high temp alarm)The fwd and aft bilge pumps do not trigger the alarm. Also turning on the ignition and turning the key to on (not start) should turn on the buzzer. Remove your left dash pannel (carefully 4 screws) and the bell will be inside to the St BD side. Test the buzzer by jumping 12v. If it doesn't buzz replace it they are a few bucks... hope this helps... if this isn't what you're looking for ill try again

 

[maestro7879]

The information about the bilge not setting the alarm off is valuable and yes that's what mine looks like. I did find the bell and that's where I was looking for the voltage. I now know not to test using the bilge alarm. I do have the three lights on while the engines are running so I will have to look into that. Any idea what would trigger them ? oil , temp are fine.

 

[rondds]

Jason, sort of a hijack and sort of on topic...the alarm sounds for stbd engine stuff only and for the generator (during start up). Port key doesn't trigger a sound when starting up even when a light comes on, there's no alarm. All the lights are functioning, even the shower sump light. Are there two buzzers (one for each engine)?

 

[Pyrojodge]

Hey Ron,

I want to say that the (1) buzzer buzzes for both port and stbd on mine. Since there is low oil pressure on either with the key on.

Maestro,

Look at all of the grounds and connections. You must have something either jumping or shorting out if they are on while running and you are certain they are fine. I am not sure of the sending units and their locations sorry...

 

[daddy d]

I have issues with the same panel, do you know what size fuse is used for the control board, and what is the resistor color code located just above and to the right the fuse. Thanks

 

[hottoddie]

The Mercruisers most likely use the same type of sending units as my Crusaders. Each engine has 2 oil pressure sending units. They are located under the left exhaust manifold toward the rear of the engine on the side of the block. The large dome shaped sender with 1 wire sends the signal to the oil pressure gauge on the dash. The other is smaller with 2 wires the completes the circuit to the systems monitor. To test the sender remove both wires and touch them together with the ignition key turned on. If the alarm sounds then the sender is bad or you have a bad connection on it or a bad wire to the systems monitor. In a 340 with engines close together they are hard to see and reach but a least you know where to look. FWIW My port sender is not working right now and I am replacing all 4 sending units as preventive maintenance as the are 26 years old. If they fail when underway you can loose all the engine oil into the bilge and also major engine damage, not worth the risk.

 

[dbmathison]

I have issues with the same panel, do you know what size fuse is used for the control board, and what is the resistor color code located just above and to the right the fuse. Thanks

Did you ever find out the resistor value? Looks like have the same issue...

David