Wiring Harness Connection

[marty1000]

I recently bought a boat with a 2002/3 Yamaha 150hp (150TXRB).
I've been having problems with my engine oil tank not filling and have had to top up manually.
While inspecting my engine yesterday, I found an electrical connector that wasn't connected. Its at the LH side close to where the main harness comes into the engine. I assumed that this was my problem so I connected it up. When the ignition was turned on without starting the engine, the alarm was buzzing. When I started the engine, the alarm continued to buzz. I'm assuming the previous owner disconnected it so the alarm was not on.
(The alarm sounds when the engine oil tank gets to low position still).
the connector on the male side has two wires, a green and a green/red. The connector on the female side has a black wire and a gray wire to one terminal and a red wire on the other.
I disconnected it and my engine and everything else works.

Any help in identifying what this connector does and if it could be the source of my problems would be much appreciated.

Thanks

Martin

[boscoe99]

Hard to say for certain but those appear to be the connectors for the trim/oil harness that runs from the motor to Yamaha gauges. If so, they are not supposed to be connected together as you found out.

Are there Yam gauges installed in the boat? If not, you might want to install them as they are very useful when trouble shooting oil transfer problems, such as the one you are having.

I don't believe the connectors you found have anything to do with the oil transfer system.

Is there oil in the remote oil tank?

Does the pump run when the manual oil transfer toggle switch is pressed?

If the pump runs, but no oil flows from the remote tank to the main tank you need to inspect the oil filter at the back of the remote tank. That or possibly an oil hose is kinked or pinched close.

Before you go troubleshooting further, and connecting connectors together that are not supposed to be connected together, you might want to get a service manual and read up on how the system works. You don't want to try and solve a small problem and in the process create a big problem.

[boscoe99]

Oh, you might want to put some grease in the switch slide mechanism. It looks dry.

[Seacraft12]

i had the same problem on my 115 with the alarm sounding in the key on and run position. i spoke with 2 yamaha techs and they said the gray wire should not be connected. i don't know what it does but i don't have an alarm in the key on position any more. gauge still reads oil level without it connected and calls for oil when it needs it.

[marty1000]

Hi there.
yes, the remote oil tank is almost full.
No, there didn't seem to be any oil being pumped from the remote oil tank to the engine tank. I guess I would hear the pump, pumping if it was working. The oil level in the engine tank didn't seem to go up when I used the switch either.
There are Yam gauges on the boat but not the digital one. Just the old dial type. I cant see any other lights in the gauges to point to the problem.
Could it be that the level switch in the remote tank is not working and showing empty and so wont pump?

thanks.

[boscoe99]

You may or may not hear the pump running. It is quiet and usually buried in the bowels of the boat along with the oil tank.

If the oil pump has 12 volts to it, and a ground lead, it should run. If not, the pump has failed.

Check the pump for the presence of 12 volts with the key turned on. Then, check for the presence of a ground connection when the manual transfer toggle switch is pressed. What do you see?

Are you following the trouble shooting procedures listed in the service manual?

[FabricGATOR]

Hi there.
yes, the remote oil tank is almost full.
No, there didn't seem to be any oil being pumped from the remote oil tank to the engine tank. I guess I would hear the pump, pumping if it was working. The oil level in the engine tank didn't seem to go up when I used the switch either.


thanks.

I'd venture to bet the remote oil tank pump has rusted through. (Died)

The design of the remote oil tank on my 2000's, it is a steel cased pump that is pressed into the molding of the tank structure. It is a great place to capture and store bilge and washdown water... thus causing the pump to rust out and eventually fail.

Pull the tank out and inspect the transfer pump motor. I've ended up replacing both of mine within months due to same failure.

PS I coated my new $160.00 pumps in the waxy oily corrosion spray for marine use prior to re-installation to help protect it from re-occurrence.