Oil level alarm?

[Speedcop]

Hi All,
Can somebody please help?
Motor is a 1999 Yamaha 130 BETO 205 hours on the clock. After fitting fuel pump kit, plugs, filters, thermostats, primer bulb and new fuel filter and fresh oil, it runs like a dream... I can ***** without any problems or I can go to WOT and it goes like a demon. BUT, if I go to WOT, after 10 seconds, the oil warning buzzer sounds, the motor goes into limp mode and the three indicators on the dash gauge flash, signifying that the engine oil tank is low.
I stopped immediately and checked the oil level in both engine oil tank and the motor mounted tank only to find it was full to the maximum mark on the tank. The remote tank had about 15 liters of oil in it. The motor heat felt normal and there was no overheat indication. I went back to port, removed the engine oil tank, cleaned it out, (no dirt in the filter), refitted the oil tank and checked the oil pump operation. It fills the engine tank to the mark and switches off. If I remove the sensor unit from the tank, it works correctly and sounds the buzzer at the low point.
It idles fine and gets out of the hole in about 2 secs, but if I go to WOT, after about 10 seconds, the oil indicators flash and it goes into to limp mode. The strange thing is that this only occurs if I exceed 5100 rpm. If if run it under 5000 rpm it will go fine all day but the problem remains!
Could this be something in the electrics? Sorry to be so long winded but I'm stumped!
Any advice would be much appreciated.

[boscoe99]

Check your battery cable connections at both end. Clean them thoroughly and then reattach. See what happens.

[Speedcop]

Oil Warning?

Thanks Boscoe,
That does make sense! I didn't mention that my son tried to start the motor but had left the kill switch off which resulted in him running the battery completely flat trying to start the motor! I had to jump start it using another boat's battery with jumper cables. The terminals were not removed. Perhaps one or other terminal got hot and caused the problem. I am just puzzled as to why this would specifically cause the oil warning to activate??
I will clean the terminals when time permits and try it again on the weekend.
Thanks again for the prompt response.
Kind regards,
Dennis.

[Speedcop]

Oil warning?

I am still just puzzled as to why this would specifically cause the oil warning to activate??

[rodbolt17]

all three indicators flashing would mean the oil control module sees SWB(remote tank) and SW3 (engine tank) closed.
when that occurs it should turn on the transfer pump for 180 seconds.
does the oil transfer pump turn on?

[boscoe99]

I am still just puzzled as to why this would specifically cause the oil warning to activate??

I can't tell you specifically the logic that is going on within a CDI for this condition. Yamaha is very, very weak when it comes to providing theory of operation.

Normally, all three lights would illuminate/bars flash if the remote tank has oil and the main tank is low on oil. A disconnected main oil harness will also cause this condition.

However, you have stated that both the main tank and the remote tank are full.

You are reporting the problem only at high RPM. My best guess is that at high RPM your motor is consuming more power which is resulting in a voltage drop within the oil control system. This low voltage can cause the conditions that you reported. Bad battery cables and connections can cause low voltage.

This is just a wild eyed guess. Try it and see. Let us know what the results are.

[Speedcop]

Oil warning?

Hi Rodbolt,
Thanks for your input.
Yes, the pump does activate, and will carry on filling the engine tank until I turn the motor off at the ignition (key). If I turn the motor off at the ignition, and wait 5 seconds, everything goes back to normal. Then I try going to WOT and at 5100 rpm the buzzer sounds and limp mode activates again. I tried switching off and selecting neutral, but before the boat comes off the plane I start up, go into gear and everything is fine again up until 5100 rpm. If I keep the motor at 5000 rpm or lower, I can cruise all day without a problem. Oil pumps as per normal.

[boscoe99]

Rodbolt is referring to the initial oil transfer mode such as when a boat and motor are placed into service. The remote tank will be filled and the main tank will be empty.

When the key is turned on the buzzer will sound, all three bars will flash and oil transfer will commence. The oil pump will stay on for up to either three minutes or until such time as the main tank is full.

If I understand your problem, you have both tanks full of oil yet you are getting an unusual oil system anomaly on your tachometer and the motor goes into RPM reduction mode, but only at 5100 and above. So, it sounds like the oil transfer system is working normally (remote tank keeping main tank filled with oil) but you are getting an alarm? An unusual alarm at that.

Agree or disagree?

[Speedcop]

Oil warning?

Hi Boscoe,
Thanks for your input. Yes I do agree!
As I mentioned before my son tried to start the motor and ran the battery completely flat. (Forgot the kill switch!) I had to jump start it with jumper cables. Would this perhaps have caused damage somewhere? The motor starts fine and all deck lights are bright. I'll clean the terminals and try it again.
I checked the charging output at 1500 rpm.. it reads 14.8 volts DC
Is there anything else I should look at, or try?
Thanks again.
Dennis.

[99yam40]

Did you charge the battery up with an external charger after it was run down all the way or are you just letting motor charge it back up?

[Speedcop]

Oil warning?

Hi 99yam40,
Guilty as charged!!!!
I just went out onto the lake in the hopes that the motor would charge the battery. I have now put it on an external charger, that when the battery is fully charged, will go into trickle charge mode.
Thanks!
After reading Rodbolt's and Boscoe's comments, I think we may just be on the right track. I will post the results on the forum.
Thanks so much guys!
Dennis.

[Speedcop]

Low oil alarm still!

Hi Guys,
I have now checked all connections and harnesses, the battery terminals have been cleaned, the battery is fully charged, oil and fuel filters cleaned and both oil tanks are full and the engine tank sensor unit is working as it should. However if I exceed 5100 rpm or try to go to WOT, the alarm sounds and the tachometer flashes low oil in the engine tank and the motor goes into rpm reduction mode.
Below 5100 rpm it will run, ***** or idle all day with no problem!
I have tried a separate 1 gallon fuel tank, gravity fed, bypassing the fuel system, no problem there!
The oil transfer system seems to be working normally (remote tank keeping main tank filled with oil) but the problem is still there? - Is there perhaps some anomaly within the tachometer or the rev limiter that could cause this?
I am about to be committed to a mental institution!!

[rodbolt17]

3 bars flashing means the oil control module sees SW# closed,shorted to ground or the module is bad.

the oil control monitors both engine tank level and remote tank level.
engine and remote levels ok,far right bar or green lamp.
remote tank low center bar or yellow lamp.
engine tank low and far left bar or red lamp.

engine tank low,SW3 closed and remote level OK,SWB closed, you get 3 bars flashing,audible, RPM reduction AND the transfer pump runs for 180 seconds or until SW1(top switch in the engine tank) closes.

if all is working and battery voltage is in range at WOT then I would suspect an oil control module failure.

all the switchs can be monitored with a multimeter while running as can battery voltage.

[Speedcop]

Low oil alarm still!

Hi Rodbolt,
Thanks for that. - I can't check the control unit (part number 6E5-85740-02-00) as it's a sealed unit.
I took the engine oil tank sender unit out and moved the sensor to the top. It registered 'OK' on the tachometer, and when I moved it down to the bottom, the three indicators flashed, the alarm sounded as it should, lifting it about an inch or two, the alarm stopped and the indicators showed OK again, so I assumed that everything is working as it should. The [remote tank] test gave center bar (yellow) low and (green) (right) bar with one and a half gallons of oil in it.
Out on the water, with the cowling off and the engine oil tank on the full mark, the problem is still there. I have thoroughly checked all connections including battery terminals on both sides. The battery is fully charged. Charging output at 1500 rpm is 14.8 volts DC.
I suspect you're right - Control module. However the price of one here is around $240 which converts to about ZA R2,600 !! Is there any way I could order one from your side at a better price? Alternatively maybe I should borrow another one to try?
Dennis.

[rodbolt17]

if you could borrow one that may assist in testing.
however I would still check battery voltage at WOT before attaching a known good module.