2003 Yamaha 115 Oil not pumping

[jburn25]

I am rebuilding an Xpress center console boat with a 2003 Yamaha 115 2 stroke. At some point during the rebuild the oil stopped pumping from the large remote reservoir to the small engine mounted reservoir. The cables seem to still be hooked up correctly and the engine is definitely getting power as I can still start it/trim/etc.. The alarm goes off when the engine reservoir drops but as long as I keep the small engine reservoir topped off it will run fine. The "emergency" pump switch on the engine doesn't do anything. Used to be that when you turned the key to "on" or "acc" you could here the oil pump. Now..nothing. When I unhooked the oil tubes from the bottom of the main reservoir oil drained through the filter just fine.

Does all this add up to mean the pump has gone out? What good does the emergency switch do? (ie does the emergency switch have its own pump)

 

[99yam40]

Re: 2003 Yamaha 115 Oil not pumping

oil pump will not run in automatic mode if remote tank is low, but the E switch should make it go.
Pump is possibly bad or the oil module or wiring

 

[boscoe99]

Re: 2003 Yamaha 115 Oil not pumping

The emergency switch does not have its own pump. All it does is ground the remote tank pump to make the pump run and transfer oil.

Keep in mind the way that this system works. Very important. With the key in the ON position, 12 volt positive power is applied to the pump on the remote tank. Either the CDI/ECU applies a ground to make the pump run or the toggle switch applies the ground. Not like a house where a light is grounded all of the time and when the switch is activated power is applied.

If the pump is not running the first thing to check is the pump. Apply power directly to it. If it does not operate the pump is kaput. If it does run there is another problem. For example, there is a small filter in the oil line at the remote tank. If the filter is clogged then oil will not flow from the pump to the motor. Or, the ground wire from the toggle switch to the remote tank pump does not have continuity.

An electrical harness connects the remote tank pump to the main engine harness. Disconnect and reconnect that harness several times at both ends. This will try and scrub off any corrosion there may be within the connectors.

Once you have found and fixed the problem you might want to consider verifying that the alarm system actually works. There is a small drain sump on the main oil tank. It is attached with a zip tie. Remove the zip tie and then remove the sump. Let the oil drain into a clean container until the main tank is empty.

With the remote tank filled and the main tank empty (after replacing the sump of course) turn the key to the ON position. You should hear the warning horn. If a multifunction tachometer is installed you will see the oil bars flashing. Shortly thereafter you should see oil flowing to the main tank. The remote tank pump will run until the main tank is filled, or for three minutes time, whichever occurs first.