Yamaha 1986 220HP oil pump not stopping

[Bullet1750]

Hi I have had this motor since new, of late I am findind that the remote oil pump is not stopping and overfilling the engine mounted tank to the point the cap pops out. If I leave the motor down and turn on the ignition (but not starting motor) and drain the engine tank halfway down you here the remote pump start and when it fills to the top mark it stops, however when operating the boat it does not. Am considering getting a new level switch set up for the top tank thinking that there might be a problem with vibration and the reed switches. Any help would be great. Craig

[99yam40]

Test the system first to see what is going on before replacing parts.
Sounds like float is hanging up or you have a wiring problem.
Does this motor have an oil module? If so that maybe the problem

[Bullet1750]

Thanks for the reply, I will take a closer look tomorrow night I have the Australian Open tennis tonight.

[Bullet1750]

OK I gave it a dry run, with the float switch in my hand I can stop and start the pump but the pump only stops when the float is at the very top no room for error, if I turn the float over the pump will not stop at all. I believe the magnet in the float or the float itself must be the problem. Any thoughts?

[Aleutianwest]

oil pump

is your trim meter working right that might be part of your problem

[99yam40]

Sorry, but I do not know what you mean by "if I turn the float over the pump will not stop at all".
Is it that if you hold the whole mechanism upside down and move the float through the ranges, the switches do not change states?

[Bullet1750]

I mean if I put the float on the shaft upside down or up the other way so the metal ring faces the bottom.

OK today I confirmed that when the motor is trimmed up the pump stops and or will not start unless you manual hold the toggle switch on the con*****er.
I have replaced the float assembly with one from a friends boat to try out. The difference between his and my switch is that his operates the shut off about 3mm lower than mine which operates only at the very top.

[rodbolt17]

dude
ya really really need to read and understand how that system works.
the trim sender has NO affct on transfer.
the oil control module uses a mercury switch to inhibit transfer,unless the key is on and battery voltage goes below about 9v.
then it will turn on and run forever.
rather than removing the switch, possibly causing more issues, test things.
check for corroded connections and such.
on your engine tank switch, white to black turns the transfer pump off,brown to black turns the pump on, red to black is second pump on command AND RPM reduction,visible and audible alarms.
testing with a plan is always preferable to pokin-n-hopin.
also if SWB in the remote tank is open or the tank is low or a wire is broken and the module thinks SWB is open, automatic transfer is prohibited.

[99yam40]

3 mm is not much difference, but did it stop it from overfilling.
apparently it does have an oil control module from what Rodbolt said so make sure the voltage it is seeing is good.

Here is something that may or may not help

[Bullet1750]

Rodbolt 17, I have read the service manual and understand how the system works, the 220 HP does not have a mercury switch it is connected to the trim sensor. The system as it was worked perfectly when testing was carried out on dry land but at speeds approching 100mph (It is a ski race boat) is was not stopping. The good news is after a full day on the water with the new level switch its working perfectly.............Yippee

Thanks for the attached file its actually better descibed in there than in my book. Cheers.

3mm made all the difference

[rodbolt17]

yamaha v4 and v6 2.6L engines used an oil control module and a mercury switch until 1990.\
1990 to 1995 the V6 2.6 L incorperated the oil control into the ECU and eliminated the mercury switch and used the trim sender.
all V6 1996 and up eliminated the trim sender as a shut off and used a pulser coil signal.
all 3.1L v6 used a pulser signal to inhibit transfer with engine off.
thats just how it works.
V4 used the module up to today but about 2002 and all replacement modules since then, use a pulser coil signal and eliminated the mercury switch.

[Bullet1750]

I appologise, I must have read the manual incorrectly, the manual I have covers about 15years worth of models. The main thing though is its all working fine with the new level switch my best guess is that the old switch which was now only switching when the float got to the very top was having trouble making to the very top with the the large amount of trim angle we run the engine at. The crazy thing about it all is my old level switch is working fine on my mates fishing boat also having said that time to order new replacement and give him his switch back.

Thanks for you input

[Bullet1750]

Problem has re occurred this weekend......bugger

[snaphead101]

Mate I've just had the same problem with my 1996 150 hp. Does yours only occur after several hours use ? The reason I ask is one of the posts mentions that the pump will activate if the voltage drops below 9 volts. So maybe your battery is loosing power after awhile or the heat from the engine changes the resistance in the wires going to the switch. Not sure if this is possible as I'm not an electrician, but I'm clutching at straws at the moment too.
I've just taken out my main oil tank and oil reservoir , drained the oil , washed with petrol and flushed the lines with petrol. If this rectifies the issue I will let you know.

[Bullet1750]

Its seem to be at random, I am an electrician and I hate intermitant faults, the wiring is spotless no corrosion, the battery is new, sitting with the boat on the trailer and testing everything works as it should. I will do a resistance check on all the conductors during the week.