Faintly chirping alarm while Volvo 4.3 GL running

[harleyfool]

A new boat for us - year 2000 Regal 180 LSR with Volvo 4.3 GL with SX-M stern drive. Apparently fresh water use with aftermarket hour meter @86 hours. Boat is very clean so hopefully hour meter is close to reality. Live in Nova Scotia. Boat brought up from Maine. Unfortunately no written history. Told winterized at dealer in fall 2008. I checked all fluids and OK. No leaks and replaced battery.

First trip with boat noted that alarm beeped loudly when key/ignition is accessory position. When boat started the beep disappeared. Noted all the gauges worked except temperature gauge. Took about 20 minute trip. Checked water hoses and not too hot. Upon return decided gauge was malfunctioning and replaced gauge and sender with auto store aftermarket unit while awaiting warranty Faria replacement.

Took second 45 minute trip with boat and noted that temp never exceeded 150. Thought this was a little low - perhaps gauge misreads low? But when started up the boat the loud alarm beep dropped in volume to barely audible chirp. The faint beep/chirp will not go away. Rechecked all fluids and they were fine. Water hoses are warm but not hot. Restarted engine several time and the faint beep/beep/beep...... will not go away.

Any thoughts? Bad alarm? short? How do I know I am not overheating and the replacement gauge/sender are duds??

Andrew

 

[P 0 P E Y E]

Re: Faintly chirping alarm while Volvo 4.3 GL running

For over heat alarm, the engine has a normally open switch. If the engine overheats, this switch closes and gives the over heat alarm buzzer and light a good ground and you get the audible alarm and visual light.

For low oil alarm, the engine has a normally closed switch which gives a ground to a buzzer until the engine gets some oil pressure, this is why you turn the key on and hear the buzzer...after the engine starts the buzzer goes off.

The pressure gage and temp gage are different animals, they have variable resistors or sending units on the engine that are not part of the buzzers.

If you are getting a faint buzzer all the time, you may just have a tired or weak oil buzzer switch on the engine or a short to ground in the oil buzzer circuit.

You can try to temporally remove the wire from the oil switch to see if the noise stops. Also check to see if the buzzer is not secure behind the panel and making contact with other wires.


One other thing to always check, the main wire harness junction or plug where the wires connect from the panel to the engine, salt and poop on this connection can cause all kinds of science.

 

[harleyfool]

Re: Faintly chirping alarm while Volvo 4.3 GL running

Good advice to start the search.

Where is the oil pressure monitor (or whatever sends the signal from the engine to the buzzer) located on the engine - Volvo 4.3 GL PEFS? I printed off the Volvo owner's manual and it is not detailed enough.

The oil pressure gauge on the dash has been working and reading midrange pressures of >40?. Does the buzzer/alarm use a different sender than the dash gauge?

 

[P 0 P E Y E]

Re: Faintly chirping alarm while Volvo 4.3 GL running

Gages use senders mounted on the engine, alarms use switches mounted on engine.

The switches are slimmer and the senders are fatter.

The temp sender and over heat engine switch ( I call it a switch cause it is normally open and closes with temp) is usually high on the engine and near the thermostat housing (the big hose on the engine shaped like a sideways horse shoe)

The oil sender and normally closed switch are usually near the oil filter , on the side of the block and or near the distributor. generally the light blue wire is the oil psi wire.

 

[GramSandy]

Re: Faintly chirping alarm while Volvo 4.3 GL running

For low oil alarm, the engine has a normally closed switch which gives a ground to a buzzer until the engine gets some oil pressure, this is why you turn the key on and hear the buzzer...after the engine starts the buzzer goes off.
We are new to boating. We bought a used 2005 18' Stingray 180RX last fall, had it winterized and are just beginning to use it. When we start it, an alarm sounds for a short while and then goes off. Can I assume from the quote above that this is normal--no mention in manual :-( Thanks!B]

 

[P 0 P E Y E]

Re: Faintly chirping alarm while Volvo 4.3 GL running

For low oil alarm, the engine has a normally closed switch which gives a ground to a buzzer until the engine gets some oil pressure, this is why you turn the key on and hear the buzzer...after the engine starts the buzzer goes off.
We are new to boating. We bought a used 2005 18' Stingray 180RX last fall, had it winterized and are just beginning to use it. When we start it, an alarm sounds for a short while and then goes off. Can I assume from the quote above that this is normal--no mention in manual :-( Thanks!B]

I would assume so. If the alarm stops making noise, athe gages read green you are good to go. The oil pressure takes a couple of seconds to reach the oil pressue switch.

Do check the engine fluids each and every start