test oil injection

[383cross]

I have a 86 115 Johnson with oil injection, how do I know the injection system is functioning correctly? Boat has a bulb for the fuel and a bulb for the oil, when i squezze the oil bulb it seems pretty solid, so how do you know if the system is working before you burn up the motor and discover there's a problem??

 

[tashasdaddy]

Re: test oil injection

you fill your oil tank, then run the motor, keeping track of the fuel used, then calculate the amount of oil used from the oil tanks. if you think you are having a problem, it is advisable to mix oil with your fuel 50:1, until you are sure your oiling system is working properly.

 

[jhebert]

Re: 1986 OMC Oil Mixing System

Re: 1986 OMC Oil Mixing System

If you have concern about the oil mixing pump, run the motor on fuel with gasoline and oil pre-mixed at 50:1 until you verify the oil mixing pump is working properly.

The OMC oil system has a sensor in the oil mixing pump that monitors for the flow of oil. It compares the oil flow rate with the engine speed. If the oil flow rate is not in proper proportion to the engine speed, an alarm will sound. If your aural alarm sounder is working you will get an aural alert if there is a problem with the oil flow. The OMC oil system is unique in this capability; it actually monitors flow of oil from its oil mixing pump. This should be explained in your owner's operating manual that came with the engine.

As mentioned above, observation that the oil level drops in the oil reservoir is a good indication that oil is being pumped.

I would not call this an "injection" system. The oil is not injected anywhere. It is just mixed with the gasoline. There are newer systems for engine lubrication in which the oil is actually pumped around to various points and injected into the engine to lubricate those areas, but that technique is not used in a 1986 motor. The oil and gasoline are simply mixed together in the oil and fuel combination pump and sent to the carburetors. There are no injectors, just a simple diaphragm pump. I do not believe that OMC uses the term "injection" or "injector" with respect to this system in any of their literature.

 

[R.Johnson]

Re: test oil injection

The service manual show's how to do this using a 1/4" I.D. clear plastic tubing, and a 12" scale, or ruler. You also need a low reading pressure guage. The guage makes it easier to count the pump pulses. The manual will tell you how much oil will be used per pump pulses at a set rpm. This will tell you instantly how much oil is used instead of running the engine, and trying to measure oil drop in the oil tank. This test will also tell you just how fast that pump will suck in oil if you have a fuel restriction. I made a free standing oil guage to make this test. My wife has yet to mention that her dress making tape is now 12" short.