Oil pump problems, Yamaha

[J_R_J]

I have a couple of oil related problems with my Yamaha 200 from -84.

The remote tank pump won?t stop filling up the main tank. As soon as I turn the key, the remote tank pump will start filling up the engine tank and it doesn?t matter if the main tank is full or not, it will continue to pump until the main tank is flooded.
I removed the level sensor from the main tank and moved the float switch by hand to the upper position, but the remote pump keeps pumping oil anyway.

Another strange thing is that the alarm only starts when the float switch is half way down, approx where the remote tank pump should start pumping oil to the main tank. When moving the switch all the way down to the bottom, the alarm stops.

I connected another main tank level sensor from my Yamaha 115, but that didn?t make any difference. I also change the oil control module, but no difference.


Last but not least, the oil level sensor in the remote tank is also giving me a hard time.
It doesn?t matter if the float switch is moved all the way down or all the way up, the green lamp on the oil level gauge is lightened all the time.
And even if the float switch is moved by hand to the bottom, the remote tank pump will start pumping oil as soon as I turn the key. It shouldn?t do so when the level sensor tells the oil control module that the remote tank is almost empty.


I bought the engine this spring and the previous owner had disconnected the whole oil pump system, so maybe it?s some sort of wiring problem?

Maybe Rodbolt can come up with something?

 

[rodbolt]

Re: Oil pump problems, Yamaha

do some forum searching on precision blend.
and lets call the tanks what I wish.
remote tank is in the hull engine tank is on the engine.
keeps me from getting confused.
for the tach green and yellow lamps. these are controlled by the remote tank switch called SWB.
switch open and the yellow lamp lights.
a quick test,key on engine off simply unplug the remote oil tank 4 pin connector and the yellow should light,may take a few seconds.
if the green lamp stays lit check for shorts to ground in the blk/red wire to the tachs green/white wire.
what are your engine tank switch wire colors?
and remember low operating voltage at the oil control module yellow wire can cause pump on in that model range.

 

[J_R_J]

Re: Oil pump problems, Yamaha

Thank you for your answer Rodbolt!

I did some more testing yesterday, and it seems as both the engine tank switch and the remote tank switch is broken.

The engine tank has four cables. Black, white, brown and red.
With a little research I found that black = gnd, white = tank full, brown = tank half full and remote tank pump should switch on, red = engine tank empty and the alarm starts.

If I hotwired the cables on the oil control unit I get these results.
Black + white ? remote pump doesn?t start, tank is full.
Black + brown ? remote pump starts, and stops when I change the wiring back to black + white.
Black + red ? alarm goes of and remote pump starts.

Did the same thing with the remote tank switch.
If I connect the black to black/red on the cables that goes from the oil control unit to the remote tank switch, the green lamp is lightened and the pump starts if I connect the black + brown cable on the engine tank switch.
And if I disconnect the black + black/red, the yellow lamp is lightened and the pump won?t start if I connect the black + brown on the engine tank, cause the remote tank is almost empty.

So the oil control unit seems to be working fine.
It?s just the tank switches on both the engine tank and the remote tank that doesn?t give the right signals to the oil control unit.
Or maybe you have any other ideas, Rodbolt?

The only thing that confuses me now is that when the black + black/red wire on the remote tank switch is disconnected, and the black + brown cable on the engine tank switch is connected, the emergency pump switch on the oil control unit doesn?t work.
Or is it just when the black + red cable on the engine tank switch is connected that the emergency switch works?

 

[rodbolt]

Re: Oil pump problems, Yamaha

re read.
when you dissconnect the blk\red and or the black at the remote tank the oil module sees that as SWB open.
yellow lamp is lit and automatic transfer is prohibited.
use a multimeter and simply test your switchs.
on SWB float down no continuity float up continuity, or simply look at the yellow and green lamps. if they work SWB is ok.
on the engine tank black is common for all 3 positions,float up white has continuity for pump off,brown when float is about the center has continuity for pump on and float down red will have it for a second pump on and the alarm.
however like I said,low voltage can cause the oil pump to simply run key on or off.

 

[Safebet]

Re: Oil pump problems, Yamaha

Completely disconnect the Oil injection system. Then you don't have to worry about engine getting oil. I did and now I can run without worrying. I just add my oil at the gas pump along with my Stabil.

 

[rodbolt]

Re: Oil pump problems, Yamaha

i see more oil related issues with premix motors than any yamaha oil system failures.
normally when trying to mix 100 plus gallons at a time.
if you mixing 6 gallons or so its easy not so easy on built in tanks.
its simply to easy to properly test and maintain the yamaha PBS system.

 

[J_R_J]

Re: Oil pump problems, Yamaha

re read.
when you dissconnect the blk\red and or the black at the remote tank the oil module sees that as SWB open.
yellow lamp is lit and automatic transfer is prohibited.
use a multimeter and simply test your switchs.
on SWB float down no continuity float up continuity, or simply look at the yellow and green lamps. if they work SWB is ok.

When I measure the impedance on SWB, it shows a closed loop no matter how i move the float switch. And the green lamp is always lit.
So I guess that SWB is broken then?

on the engine tank black is common for all 3 positions,float up white has continuity for pump off,brown when float is about the center has continuity for pump on and float down red will have it for a second pump on and the alarm.
however like I said,low voltage can cause the oil pump to simply run key on or off.

Measured the same thing on the engine tank and it seems as that one works.
But I can't get the emergency switch to work, no matter how i move the engine tank or remote tank float switches.
Haven't measured the voltage in the yellow cable to the oil control unit though.



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