First time boat owner - mercs wont start

[315Customs]

I just bought my first boat. Its a 1988 Invader 244 23' with 2 Mercury 135 outboards.

When I turn the key on for the port side motor an alarm on the console beeps twice. When I try cranking for 5-10 seconds the alarm starts sounding non stop until I turn the ignition off. This does not happen with the starboard motor.

The starboard cranks all day and just wont start up. Both fuel bulbs get firm when squeezed. I'm waiting for a buddy to come over so I can check spark.

Any suggestions on what the alarm is and why its only one motor it does it on? Any suggestions on why neither start? I know it could be spark since I havent checked it yet but figured I'd ask opinions in the mean time while I wait for a friend to show up.

 

[CharlieB]

Re: First time boat owner - mercs wont start

The alarm module is two alarms in one.

The low/no oil alarm is rapid beeping.

The overtemp alarm is a solid tone.

The module should give a two beep self-test every time the key is turned on.

If the alarm comes on with a continuous tone soon after starting the motor it is possible that there is a cooling issue, immediately shut down the engine, pull the cover and test head temp at the top cyl on both banks. They should be warming but not so hot that you cannot hold your hand on it for three seconds.

Many V-6''s the 'P' tube does not show water flow until the T-stats open.

Is the boat in the water or are you starting with the water flusher attached and the water ON? If on the hose do you see water flow coming out thru the prop hub?

If in the water, do you see any 'mist' of water blown out the upper exhaust vents?


On the 'No Start' engine, make sure that the lanyard is plugged in.

If still no spark then disconnect the Black wire with the thin Yellow trace line from between the ignition modules and the engine wiring harness, if it now sparks then that 'kill' wire is grounded somewhere in the boat, lanyard, or ignition switch.

 

[315Customs]

Re: First time boat owner - mercs wont start

CharlieB - I have the boat on the trailer in my driveway. When attemping to start either engine I have the flush kit hooked to the water intake (ear muffs). The alarm only sounds when trying to start the port engine. It gives the two chirp test when key turned on. Then after cranking the engine a while it starts beeping rapidly until I shut the key off. Neither engine starts and I only get tones from the port side engine not the stbd side.

I don't think this boat has a lanyard feature. I at least don't see where one would go. Definetly nothing around either one of the key cylinders.

I might get a chance to check spark tomorrow and the things you mentioned.

Thank you for the detailed reply!!!

 

[CharlieB]

Re: First time boat owner - mercs wont start

Rapid beeping is an oil alarm.

The alarm module is wired to the rotation sensor on the oil pump AND also has a green wire connected to the input side of #4 cyl coil, if the module senses a difference in the two then the alarm sounds.

In case there is an oil failure you should pre-mix your fuel, either add oil to your fuel tank OR temporarily use a portable tank of pre-mix to test this motor to prevent any 'No Oil' damage.