1999 OX66 225 oil lights and alarm sounding

[SARDOG67]

I have a issue with my 1999 225 OX66. When I turn the key switch on the alarm sounds and all the indicators self check and then only the red oil empty indicator flashes on the tach for about 15-20 seconds and the alarm stops. The red indicator continues to flash for about another 10 seconds and then switches to the yellow indicator. All reservoirs are full and filters,pumps and level switches have been checked and operating correctly. It seems to be getting oil because its using oil. You can drive the boat for a few minutes and sometime up to a half an hour and the alarm will come on again and cut the engine to 2000. The indicator on the tach never goes to green. This is driving me nuts.

[rodbolt17]

sounds like you have at least two issues.
one will be with the switch in the engine tank known as SW3.

the switch in the remote oil tank,known as SWB controls the yellow lamp.
\the ECU does NOT and CANNOT control the yellow lamp.
only an open in the SWB circuit can turn on the yellow lamp.

the ECU does control the red lamp if it sees a ground path in the SW3 circuit.

IF and only IF the ecu sees the same open SWB circuit as the tach it will inhibit the automatic oil transfer function.

at the remote tank,black is an engine ground, black/red goes to the engine main harness.in the harness is a splice. typically it changes colors to green/blk going to the ECU and green/white going to the tach.

[SARDOG67]

All of the switches have been tested. At the connector I am seeing it open and close.
When the yellow light is on, I can remove the switch out of the main engine tank and raise the lower float and the red light will come on. I am going to check the harness from the remote tank and look for a open. I will also check the green/black from the main tank.

[rodbolt17]

dude.
you aint getting it.
you MUST clear the yellow lamp condition or NO auto transfer will occuer.
if it will auto transfer with a yellow lamp the fix the open circuit between the engine harness splice and the tach.

the ECU does NOT control the yellow lamp.

do some forum searching, I have beat precision blend to death,resurrected it and beat it again.
oh, and lets call the tank in the hull the remote tank.

guess what we will call the engine mounted tank ?

[boscoe99]

Start with finding the problem that is causing the green light to go out and the yellow light to go on. Once that is fixed, the other problem can be addressed.

You say that the remote, boat mounted, oil tank sensor switch has been tested and is working correctly. That is, continuity when the float is up (switch closed) and no continuity when the float is down (switch open). The switch is just one part of the equation. You need to verify that the ground is getting to the switch and once it crosses the switch that it is getting all the way back to the tachometer. Connectors, particularly those at each end of the oil harness are a known hot spot. If nothing else, disconnect and reconnect the connectors several times to try and improve the electrical conductivity.

To summarize what rodbolt says, the remote oil tank switch being closed (float up due to oil in the tank) causes the green light on the tachometer to illuminate. If and when the switch is open (float down due to low oil in the tank) the green light goes out and the yellow light comes on. If a connector is bad, if a wire is bad, if there is no ground to the switch, then the yellow light will be on even if there is oil in the tank and the switch is good.

Further to what rodbolt says, note that the black/red wire from the boat mounted remote oil tank sensor switch goes to two places. It goes to the tachometer via one wire and it goes to the CDI via a different wire. If the wire/connections to the tachometer are compromised the tach light won't function correctly. If the wire/connections to the CDI are compromised then the automatic oil transfer function won't work.

See diagram below:

[SARDOG67]

Thanks guys, found the problem. the pins in the remote oil harness were not getting ground and the #14 connector was bad. Took the connector out and grounded the black wire to the lower head. We are in the green now. Again, thanks for you help. I will sea trial it this weekend.

[SARDOG67]

Went to sea trial the boat. Before I could leave the yard, I tried to warm the motor. When I turned on the ignition it cycled the warning lights on the tach and went to green. Then I started the motor and the 3 flashing oil warning lights and the buzzer sounded again for about 10-20 seconds and then only indicated the green and the buzzer stopped. Its doing this every time now. The other day everything was working normal. I think I have an other issue. I'll let you guys know that I have emptied both oil tanks and cleaned the filters and lines during the last few weeks. Could this be part of the auto oil transfer that Rodbolt17 is talking about?

[boscoe99]

Check and recheck all of your electrical connections. At the battery, at the battery switch, at the engine end, etc. Remove the connectors and scrub them to remove any build up of corrosion. A green scotchbrite will do.

Check all fuses for cleanliness and for tightness. Maybe just replace the fuses for the hell of it.

Have you tested the battery cables for high internal resistance by doing a voltage drop test?

Get your battery loaded tested. How old is the battery?

Make sure the generator is outputting nominally 14.5 volts at the battery when the motor is running at a fast idle.

You can test the oil transfer system itself by draining the engine mounted main oil tank. Put that oil in the remote boat mounted tank. Make sure the remote tank is at least half full. Reinstall and secure the drain sump to the main engine mounted oil tank. Turn the key to the on position. Wait a few moments and the oil pump should turn on and start sending oil to the engine mounted main oil tank. The pump will run for three minutes or until the main engine mounted oil tank is full. That will tell you the system is operational.

When the key is turned to the on position you should hear the warning horn. Tachometer lights should illuminate. When the tank is half full the horn should stop and the lights should extinguish.

I suspect that you have a low voltage issue. The starting of the motor is draining the battery. Low voltage is then causing the alarms. After the motor has replenished the battery a bit the voltage is rising and the alarms cease.

[rodbolt17]

if you get an audible and 3 bars flashing the ECU is seeing sw3 closed and swb closed and will do an auto transfer for 180 seconds or until sw1 closes.

low battery voltage will trigger an audible and RPM reduction but wont affect any tach visuals.

cranking with the stop lanyard out will create an audible.

overtemp switch closes and you get an audible.

SW3 in the engine tank closes and you get a red tach indicate and an audible.

SWB open and you get just a yellow tach indicate.

SWb closed and you get a green tach indicate.

[SARDOG67]

Ok, today an other issue. Just turning on the ignition I get three oil lights flashing and the alarm. I have checked all wiring for loose connections, batteries. I lowered the engine oil tank and when I turned on the ignition it filled back up. Now when I turn on the ignition it flashes the three oil lights, alarms and after 10-20 seconds goes to green and alarm stops. Any connection that I have thought even discolored, I've repaired it. When I tested voltages all were 12.6-12.3 when cranking voltage drops to 11.8-11.9. Seems fine to me.