Low Oil in Remote tank

[crabcake]

I have a 1996 Mercury 225 Offshore (carbs). If I leave the motor tilted up for several days the oil level goes down in the engine mounted oil tank. Thus, when I try to start it the low oil alarm goes off. I have to pull the cover and fill the engine mounted tank, solving the problem. (what a pain) It only seems to happen after several days in the tilted up position. Oil system works fine while underway and no other problems. There seems to be no signs of oil leaks. Does the tank or the hoses have a check valve? If so, where is it located? Would this cause oil to drain back into the main tank? Thanks for your help.<br /><br />crabcake

 

[The Marine Doctor]

Re: Low Oil in Remote tank

Generally an air leak will let the oil run back into the tank, but if you have an air leak the oil tank should overflow from that spot.<br /><br />TMD

 

[gss036]

Re: Low Oil in Remote tank

The oil system is pressurized and forces the oil from the boat tank to the tank inside the cowling.That is why TMD says it should leak at the point of the air leak. How much oil is leaking and where is it going? It should not be going back into the tank if the system is holding pressure.

 

[greasemonkeyozi]

Re: Low Oil in Remote tank

What happens if you leave your motor down? You dont really need to keep your motor tilted up when the boats just sitting, its not good for the transom, let the ground hold all that weight. <br /> Docs right though, an air leak would cause the oil to drain back into the tank.

 

[rodbolt]

Re: Low Oil in Remote tank

Hello<br /> if you will look at the design of the oil tank it will be clear. it looks and acts like a teapot when tilted up. the oil line into the tank should have been on the aft end of the tank not the forward.but I am not an engineer I just have to deal with the customers they tick off.<br /> I have solved many of the problems of oil draining from the engine tank back to the hull tank by simply installing the fuel line check valve from any late model V6 yamaha into the merc oil line with the arrow pointing towards the tank. presto, engineering defect solved.<br /> <br />wish I made what they did shooda stayed in skewl

 

[Troy_from _Oz]

Re: Low Oil in Remote tank

Rodbolt - Its NEVER an engineering defect. Its known as being "part of the engineering design" - but never a defect!!! hehe<br /><br />Cheers<br />T

 

[roscoe]

Re: Low Oil in Remote tank

An event for superior engineering extrapolation.

 

[crabcake]

Re: Low Oil in Remote tank

The motor is on a bracket (Parker 2520, full transom) and I leave the boat in the water 9 out of the 12 months a year. I don't like to leave the motor in the down position while in the slip because of marine growth. While on the trailer I leave the motor in the down position. When the motor is down I don't seem to lose any oil from the engine tank. When up, sometimes, I seem to be losing enough to set off the alarm. (12oz maybe) I have looked for leaks and there are none. Thanks for all your help.

 

[gss036]

Re: Low Oil in Remote tank

I think I would go ahead and install the Yamaha one way check valve, sure can't hurt anything and could easily solve your problem.