1990 Mariner 175 carb.......rapid machine gun beeping.

**bbezok** · 06-20-2018, 01:28 PM

Have a 1990 Mariner 175 Carb model, just started a very rapid beeping while idling into the dock. Checked oil levels in remote tank and reservoir on engine. Checked cap float and sensor and the magnet is in place. disconnected cap sensor wire and rapid beeping continued. Next morning started it at the dock, ran for a minute or two with no issue then the rapid beeping began again as the tell tale started spitting water and temperature gauge barely registering. Have a water pressure gauge and at idle it also barely registers, throttle up and it goes up to 5-6lbs which appears to be low. Everything I've found in threads points to an oil issue, could it be temperature???

**Fishinmymission** · 06-20-2018, 06:25 PM

there is a plastic worm gear on your crank shaft connected to a metal gear that has a magnet. Every two revolutions of your fly weel should rotate that magnet by the rotation sensor once. Fast beep is any part of the oil injection system. If the float sensor is not the culprit it leaves warning module, random short somewhere, or most likely failure of the plastic worm gear. The plastic worm gears are known to break causing the pump to stop functioning. I actually had a partially worn worm gear that would jump teeth at idle sometimes and more consistently as the wear increased. But at higher rpms i never got an alarm and assumed the oiling worked perfectly. When I took the engine apart there was no issues with lack of lubrication. If you ignore this and it does not get enough oil it will destroy your engine. Below is how mercury states to trouble shoot the worm gear.

Also note when I did this check i would sometimes get the pulse every 2.5 rotations. I figured it was ok but i was wrong and had a damaged gear.

Check output voltage to the sensor by connecting
voltmeter to BLUE/WHITE sensor
lead. Remove spark plugs and ground spark
plug leads. Turn ignition to “ON”. rotate flywheel while
observing voltmeter. Output voltage should
peak at 5 volts ±1 volt and then drop to less
than 1.0 volt during every 2 revolutions of the
engine.

**bbezok** · 06-20-2018, 07:57 PM

thank you for the information, will look into the worm gear test to see if that is my problem or something else.
thanks again.

**nitro_rat** · 06-20-2018, 08:04 PM

Do yourself a favor and delete the oil injection before it costs you a powerhead.

**bbezok** · 06-20-2018, 08:09 PM

how difficult or easily is that done?

**Fishinmymission** · 06-21-2018, 09:44 AM

Its easy its a nice peace of mind to find the exact cause of the oil injection alarm. Once you find out the worm gear is toast its super easy to remove the oil injection equipment and mix your oil 50 to 1. Search on the this forum or anywhere on google super easy to do.