3.0 volvo penta alarm on constantly

[yesters3]

alarm went off while cruising at 3500 rpms. all systems seemed o'k' water temp, oil pressure and engine performance and idle all good. Went home changed impeller but alarm is still on constantly. water temp checked manually at manifold pepcock and only at 120 degrees. oil in engine full also. what else could cause the continual alarm. it is sounding even when cold.
Thanks

 

[Don S]

Re: 3.0 volvo penta alarm on constantly

And what 3.0L are we talking about, need full model number or serial number. Different sensors on different models.

 

[yesters3]

Re: 3.0 volvo penta alarm on constantly

boat is a 2003 glastron 17sx and the engine model 3.0 glm-a (3869170)

 

[Don S]

Re: 3.0 volvo penta alarm on constantly

Engine coolant temp, low oil pressure, and exhaust overheat. The three SWITCHES have nothing to do with the gauge, and the all three have tan wires with a black stripe going to them.
The eng temp switch should be near the thermostat housing.
The oil pressure switch probably near the gauge sender aft of the distributor.
The exhaust temp switch sould be on the exhaust elbow.
Start the engine, and remove one of the tan/black wires at a time until you find out which one is causing the alarm. Check temp of the exhaust elbow with a temp gun to see if it's too high or not.

 

[yesters3]

Re: 3.0 volvo penta alarm on constantly

checked exhaust elbow with temp gun and barely got to 103-105 degrees. Checked all sensors as recommended and alarm goes off when i unplug oil sensor. Oil is not low and pressure seems o.k. at least it's reading 40-45 pounds on dash guage.

 

[muc]

Re: 3.0 volvo penta alarm on constantly

Good job, you found your problem.
Part number 3852215 Sensor, oil pressure $ 30.58
Is what you need.