1994 Johnson Fastrike warning horn question

[fishpro67]

Johnson ” Fastrike” 150 hp, 1994 model. The warning horn goes off as soon as I turn the key on. Not the normal “chirp”, but a constant “on”.

I have disconnected all of the sensors that use the brown wire as mentioned in other posts about this same issue. Both temp sensors at the cylinder heads, the switch on the front of the OMS/VRO mixing unit and the harness underneath the mixing unit were disconnected.

The only way I can get the alarm to shut off is by disconnecting the small harness which runs into the engine cowling on the left side along with the fuel line, oil line, and main harness. I assume that this two wire harness, brown and black wires, is the one coming from the oil tank?

If so, what part inside the oil tank will go bad? Is it serviceable by itself or must I buy the complete unit that comes out of the top of the oil tank? Also, If I turn the ignition on and disconnect the afore mentioned harness, the horn stops. If I plug the harness back together, and I get the normal single chirp. But, if I then switch the ignition off and back on, I get the constant horn again?

Thoughts on what my failed part might be?

[PBR]

I belive that is the low oil in the tank . I had the same problem The float was sticking. Tank should be cleaned once a year make sure you check your screen . Mine had a little moister in it and the screen was slimey

[316jughead]

That would be the low oil warning, should sound off every 20 seconds. You can remove the oil line and unit and clean your tank and unit. You will see that the float moves up and down the oil pickup tube. It makes contact with tube when about 1/3 full. Make sure that the float is moving freely, You can test the system out of the tank, connect the wire harness and turn on the key, move the float up and down to make contact. Sometimes the float just sticks and cleaning will fix it, other times the darn thing is just shorted to ground. You can replace the oil pickup assembly or just unplug it and always make sure your oil tank is full. When replacing the oil pickup push the oil line off the VRO and pump the oil bulb several times to get the air out of the line (I pump it 50 times). Now would be a good time to test the no oil warning, put 1 pint of oil in your gas tank for every 12 gallons of gas start the motor and run at a fast idle untill the no oil horn sounds, this could take up to 5 minutes, push the oil line on the VRO, the newer VRO's are self priming and should pick up oil and the horn should stop. Oil should be visable at the end of the line when you push it on. A very long post but I didn't have anything else to do, I ate all of the pumpkin pie.


Modified by 316jughead at 10:34 PM 11/27/2011

[fishpro67]

Thanks for the inforamtion guys! I'll get the tank out and go thru trouble shooting and cleaning.

[fishpro67]

Update to this problem. I pulled the float / oil pickup unit out of the oil tank. The float, I assume, is inside the small round device at the bottom of the pickup. It is a little smaller than a 35mm film canister.

I ohmed the two leads coming from the unit and it checks out. The float is loose as I can make continuity by pressing the shaft fore and aft. Ohms’ reading will change accordingly. However, When I hook up the two leads, brown and black, coming from the engine wiring harness, the warning horn sounds continuously.

Also, I have found that if I disconnect and reconnect the main harness (large red connector) which mounts to the left cylinder head the horn will stop. However, it seems to reset because after a few minute with the key off, and then back on, the horn begins to sound again.

This problem started on my last fishing trip. The battery was low and the motor was slow to turn over at the ramp. It did start and ran fine to the first spot. I switched off the engine but the electronics ran for a couple hours. When I went to leave the battery was dead. I disconnected one of the trolling batteries and hooked it up to the starting battery cables. When power was supplied to the engine, the horn started sounding continuously. I got the engine started and then swapped the cables back over to the starting battery.

Since then I have had the warning horn problem.

Would anyone possibly have a digital copy of the wiring schematic for the OMS system electronics so that I can trace the wires to see what my problem could possibly be?

Thx,

[SEAHORSE]

There are electronic chips inside the oil pickup assembly that generate the 20-40 second beep that signals a low oil level in the tank. Those electronics can go belly up and cause all kinds of weird horn signals.

Since it only alerts to a low oil level, and a regular visual inspection does the same thing, just disconnect the 2 wires to the oil tank and your beeping problem will go away. That is a lot cheaper than a new oil pickup assembly or a new tank.

[fishpro67]

Seahorse,
Thanks for the information. However, the warning horn on my motor maintians a constant "on" same as the "no fuel" situation. Not a 20-40 second beep cycle. Would bad electronics in the oil pickup confuse the two?

thanks, FP67

[ChampioNman]

No fuel comes on over 4500 RPM from your description, when you unhook the low oil harness everything is fine. That is why we went in that direction.

[316jughead]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by 316jughead &raquo;</td></tr><tr><td class="quote">That would be the low oil warning, should sound off every 20 seconds. You can remove the oil line and unit and clean your tank and unit. You will see that the float moves up and down the oil pickup tube. It makes contact with tube when about 1/3 full. Make sure that the float is moving freely, You can test the system out of the tank, connect the wire harness and turn on the key, move the float up and down to make contact. Sometimes the float just sticks and cleaning will fix it, other times the darn thing is just shorted to ground. You can replace the oil pickup assembly or just unplug it and always make sure your oil tank is full. When replacing the oil pickup push the oil line off the VRO and pump the oil bulb several times to get the air out of the line (I pump it 50 times). Now would be a good time to test the no oil warning, put 1 pint of oil in your gas tank for every 12 gallons of gas start the motor and run at a fast idle untill the no oil horn sounds, this could take up to 5 minutes, push the oil line on the VRO, the newer VRO's are self priming and should pick up oil and the horn should stop. Oil should be visable at the end of the line when you push it on. A very long post but I didn't have anything else to do, I ate all of the pumpkin pie. &lt;br /&gt;&lt;br /&gt;
Modified by 316jughead at 10:34 PM 11/27/2011</td></tr></table>

Like I said sometimes the darn thing just shorts out. It is shorted to ground inside the oil pickup electronics. Have a Merry Christmas, the Jughead said that! (I still love CB talk)