Oil Warning Signal with Johnson Outboard 1992, 70 HP

[MuskieTom]

After launching my boat this year, my Johnson 1992, 70 HP motor starts fine (oil injection - sepearate oil container). After running idle for a few minutes, the low oil warning tone goes on every 20 seconds or so and eventually, if I let it run, the full low warning singal goes on and stays on and then the motor dies.<br /><br />The oil supply container is full and priming the oil bulb does not seem to help. After opening the sealed oil container, I noticed a filter and feed tube with a cylinder on it. The filter was clean and priming the bulb seems to be priming oil.<br /><br />Do I need to contact a professional mechanic or does somebody have an idea of what could be causing the problem? Could it be a sensor in the throttle control?<br /><br />

 

[ob]

Re: Oil Warning Signal with Johnson Outboard 1992, 70 HP

If your engine alarm is emitting a continuous tone it is one of two things.It is either an overtemp alarm or a fuel restriction alarm.An overtemp alarm if detected will limit the rpms of the engine to 2500 or so by the S.L.O.W. feature.<br />A "no oil" alarm is denoted by rapid short tones.<br />When you initially turn the key to the "on" position do you hear one short tone verifying the alarm circuit is working?

 

[OBJ]

Re: Oil Warning Signal with Johnson Outboard 1992, 70 HP

Hi MuskeyTom and welcome to iboats forum...<br /><br />If your sure, and from the post you sound sure, that the warning was a 1/2 second tone every 20 secs' or so, and pumping the primer bulb don't help, I would be inclined to say that the "Low Oil Level" sender is kaput. This is the unit ya pulled out of the reservoir.<br /><br />The no oil alarm is an urgent 1/2 sec every 1/2 sec tone. Be very sure about the warning tones.<br /><br />Just for S*its and giggles, pull the reservoir sending unit out. Turn the key on and listen for the tone. Now move the little float up to the "Full" position. If the tone continues, the sender is bad. <br /><br />Also, check for any wires from the unit which may be cut or frayed grounding the unit which would cause the tone.<br /><br />The sending unit is around $67 US. Good Luck!

 

[MuskieTom]

Re: Oil Warning Signal with Johnson Outboard 1992, 70 HP

Wow, you guys are great. Thanks OutBoardJim and ob for taking the time to read and respond to my post.<br /><br />I will try all the recommendations. Actually, the motor seems to run fine at full throttle for about 1/2 mile, while the warning goes on every 20 seconds until it kind of weens up and down and stays on. Sounds like the sending unit is bad.<br /><br />After searching this forum and few other sites regarding the 3 cylinder Johnson 70 VRO, I have found many people recommeding to disconnect the VRO and mix the oil and gas and forget about it. Would you recommend I do this or get a new sending unit?

 

[OBJ]

Re: Oil Warning Signal with Johnson Outboard 1992, 70 HP

Hi Muskie...<br /><br />You find probably just as many folks that will say git rid of the VRO as you will that say keep it. Myself, I'd say keep it. If only for piece of mind, after you get the sender problem fixed, a test of the other warning signals would be appropriate.<br /><br />You already know about how to test the low level sending unit in the oil reservoir.<br /><br />After you get that problem fixed, mix a tank of premix gas or enough to do a little test. With the premix tank connected to the engine and the engine running, idle will do, pull the oil supply hose off the nipple on the lower engine pan. As the VRO pump uses up the oil, the urgent 1/2 sec tone every 1/2 sec. should start. This will tell you that the alarm system is working. It may take a bit for the engine to use up the oil in the hose so be patient.<br /><br />Test the over heat alarm. Look for a wire coming from the head with a rubber boot attached. The wire will be a brownish color. Pull the boot back to expose the knife connectors and break the connection. With the key in the on position, no need to run the engine, touch the harness end of the brown wire to a ground. The warning tone should be a steady tone.<br /><br />If all these alarms sound as intended, your good to go. Good Luck.

 

[MuskieTom]

Re: Oil Warning Signal with Johnson Outboard 1992, 70 HP

Thanks again OutboardJim, your information is very helpful and easy to understand. I will test the alarms and should be good to go. I will recommend this forum to many of my friends. It is people like you that make this a great forum!<br />