2 Stroke oil resevoir not working

[Pinguu]

My kevlacat runs two 2005 Yamaha 115 2 strokes (100hours) with external resevoirs for both engines.

Recently on a trip my oil alarm sounded, I stopped and took of the cowling to find the internal resevoir was only 1/3 full even though I still had 5 litres in the external resevoir. I refilled the internal resevoir after checking a few things and off I went. On the trip back same thing happened.

Their is obviously a fault between the external reservoir and the internal resevoir, and I am certainly no genius when it comes to fixing things. Anyone experienced this before or have any suggestions on what it might be ???

Any help would be appreciated.

[Heath]

Sounds like a problem with the pump that pumps the oil from the main tank to the resevoir under the cowel.
First thing I would be checking is that the pump works.

[Noelm]

I have only ever done any work on one of these once, so my info will be only a guide, first off there is a couple of sensors (actually switches, either on or off) and a transfer pump, the pump may well be faulty (rare) but more than likely, it will be one of the switches that "tells" the pump when to turn on, I think there is a way to activate the pump with the key on, motor not running and a "switch/button" to make it run, but not fully sure on your model, I have posted a question to a guy I know in the US that knows more about Yamaha than Yamaha does, so I will let you know what I find out.

[PADDLES]

don't know how the yamaha system works pinguu, but if it's similar to a mercury it will run on pressure. the main tank pushes oil up into the header tank under the cowl, the tank under the cowl gravity feeds into a little injector pump. i'd be checking for kinks and blockages in the lines. check that there are no leaks (oil or air), make sure all tank caps are done up properly and seals are serviceable. my blackmax used to leak oil back down the fuel line through the injection pump if it sat for a period of time, this would drop the level in the header tank and leave an air pocket at the top, the little tank only gets filled with oil as pressure decreases so if air gets in there it will never fill up from the main tank. i'd hit a swell and the oil alarm would sound and i'd have to fill the tank and all would be good. make sure the tank under the cowl is properly filled up as per your manual, there'll be an oil system bleeding procedure in there somewhere. have fun.

edit: maybe i was full of it and it used vacuum instead of pressure, either way check all your lines for air leaks and the o-ring seals under the caps.

further edit: i got bored enough to check this out further and your yammy one is electric and exactly how some boys on here have described. have a look on the iboats website, a guy there has asked the exact question you have asked.

[Noelm]

OK, I need to know if you have a digital Tach, and if so, why lights/info do you get when the alarm sounds!

[honda900]

Just before you go on your electrical way,

maybe just check the primer bulb on the tank to see if its primed and doesnt have air in the line, also if you undo the lid of the tank, check and see that there is nothing blocking the pickup.

Regards
Honda

[Hagar]

I am with Heath on this one . I use to have the same engine . The external tank has a pump on it to keep the smaller engine tank topped up . It is shut off by a type of float switch which from memory is part of the engine tank cap . Take off the cap and check the float ring is sliding free down to the level of the oil . With the engine tank not full ( take some oil out if needed ) the pump on the external tank should run until the float reaches the full point in the engine tank when you turn the ignition on . You do not need to start it . Do this and have a listen and go from there . Let us know what you find .

This engine can also do the opposite to your problem and pressurise the tank and oversupply oil to the engine as happened to me once if the float does not cutout .

Cheers

Chris

[Pinguu]

Thanks to everyone who has replied so far.

I have had a friend of mine on the job trying to find the problem, it is not the pump of the switch uder the cowl. This has been tested by swapping them to my second identical motor(i have a cat) and discovered them working perfectly.

We have checked a lot of the wiring in and around the motors under the cowl , all we can summize is their is a faulty wire somewhere. Very frustrating to this point.

NoelM , I have a digital Tacho, but I have not as yet checked what it displays when the alarm sounds.

I have removed all caps and floats and disconnected the oil lines between the external and internal resevoirs and checked them for blockages , none were found.

We are still stumped, may be time to call in the professionals.

Warwick

[Noelm]

I need to know what the tach has displayed, I know a guy who can tell me exactly what is wrong, do not continue to pull things to bits, you may introduce a whole new problem, then we are looking for two faults, so get the tach reading for me.

[Pinguu]

Thanks NoelM , will post the reading after my trip to Flinders reef tomorrow.