1997 Evinrude VRO alarm circuit

[PGill]

I have been doing allot of research on this site over the last couple of weeks and appreciate all the information that is available. Here is my problem that someone may be able to help me with.

1997 Evinrude 50 2 cylinder electric start with VRO

This used boat is new to me and I am checking out to make sure all the alarms are working for the VRO and overtemp. I have a pretty good idea of how all this is wired up and the signals used to control the alarm.

1. turn the key to the on position. alarm sounds for a second. self check good
2. Ground out the temp switch and the alarm sounds on steady. good
3. trip the float switch in the oil tank alarm sounds on steady. according to what I have read this should be a pulsed alarm. My wiring says it can't be anything but a steady alarm. The tan wire fro the oil tank is spliced directly into the tan wire going to the alarm. nothing in the circuit to create a pulsed output.. don't know why this is.
4. Testing the VRO alarm.
a. Tach signal appears to be good, tach is working.
b. VRO is pulsing as witnessed by the little pin on the back of the pump tripping the reset switch when the pup pulses (engine running).
c. 4 wires connected to the VRO check out. Grey-tach good, Black-ground good, purple-12vdc good, tan-output to the alarm never triggers to ground, not good.
d. This tan wire from the VRO is also spliced into the same tan going to the alarm along with the temp sensor and the oil tank. This wire when forced to ground will generate an alarm but not a pulsed alarm just steady. I'm assuming if it was to work that maybe the electronics in the VRO would send it out as a pulsed output??

Charging circuit is working.
alarm has 3 wires, Tan, purple and black

So I am at the point where I want to say that the electronics module on the back of the VRO pump is bad and not generating the output.

Any experience or insite would be appreciated.

I hesitate to run this boat without a VRO alarm. I am running premix in the fuel to now until I figure this out.

 

[Silvertip]

You can easily determine if the VRO is oiling properly by placing a mark on the remote tank to show the current oil level. Since you are premixing as well, this will not affect the VRO delivery so you can now run the boat fairly hard for at least an hour. Now stop the boat so it is in the same attitude as when you first marked the oil level. If the oiler is working the level should have dropped. The exact amount is determined by the speed you were running and the amount of time. Since you ran fairly hard (hopefully) the engine should have burned somewhere between 3 and 4 gallons of fuel. A 50 HP two stroke will burn about 5 gallons/hour at wide open throttle. Since the oiler is set to deliver oil at a rate equivalent to premix, the oil level should have dropped roughly 1/2 pint or a bit more or less. One pint in 5 gallons of fuel is 50:1. This of course is not a precise measure of oil flow but it will provide an indication that the oiler is working. As for the sounds the alarm makes, those are timed beeps to indicate low oil/no oil. Again, to test that, you again run premix but use an empty remote tank. The oiler should provide the no oil alarm. You can add a little oil to the tank to test the "low oil" alarm. You will need to prime the oil line with the bulb to get oil back into the system.

 

[PGill]

Thanks Silver tip, for the information.

I am confident that my oiler is working but I am not going to use it unless I can get the alarm signal working from this pump. I took a few pictures of the wiring for reference. The oil tank has no electrical ability to ttime the beeps, it is a simple float switch in the tank that goes to ground on low oil and then sounds a steady alarm. The overtemp wire is the same way. I cannot get a a signal to ground out of the tan wire coming from the VRO. I have ran the engine for 20 min. with the oil disconnected, I have watched the trip/reset switch stop sending pulses and the tan wire never sends a signal. if I force this tan wire from the vro to ground the alarm sounds steady so the wiring is good.

The only thing I can surmise from this exercise is that the VRO electronics are bad or they are not counting the Tach signal in order to generate the the alarm.

I found information on this site that describes how the signal on the VRO is processes. If the engine is running and the reset switch on the pump does not trigger a reset in 8000 counts of tach signal it will set the tan wire to ground to sound the alarm. Not sure if the same electronics on the VRO actually sends timed beeps or steady.

I find this interesting and fun to troubleshoot and I hope this information may help someone else do the same.

Thanks for the help