Diagnosing OMS/VRO issue

[SeaArk]

I have a few question about the 2000/115 HP Johnson that is over oiling. The following are items that could cause this symptom.<br /><br />1. Oil lift pump failure.<br />Q. Where is this component located ?<br /><br />2. Restriction (pinching) of the oil return line.<br />Q. Where is this component located ?<br /><br />3. Oil injector failure.<br />Q. Where is this component located ?<br /><br />Thanks in advance for any input.....

 

[seahorse5]

Re: Diagnosing OMS/VRO issue

You forgot the most common cause of over oiling which is air leaks in the fuel system that causes bubbles in the gas. It is easily diagnosed by temporarily installing a clear fuel on the OMS inlet fitting and running the motor at all speeds. If you "Tee-in" a vacuum gauge, you can also check for any fuel restrictions.<br /><br />The factory service manual gives a good explanation and has photos of how to troubleshoot OMS and fuel system problems. I recommend you obtain one and understand the system and procedures before "tearing into" the engine.

 

[SeaArk]

Re: Diagnosing OMS/VRO issue

I have already checked for air leak and did not have one. I also bypassed the oil injection part of the pump and am currently pre-mixing. Runs fine like it is with pre mixing, but I like the convienence of not having to pre mix.<br /><br />I also have the OMC repair manual but it is not clear as to where the items are in regards to my initial post. So if anyone can enlighten me as to how to identify those items it would be most apperciated.

 

[seahorse5]

Re: Diagnosing OMS/VRO issue

What is the part number printed on your manual?

 

[SeaArk]

Re: Diagnosing OMS/VRO issue

It is p/n 787070

 

[SeaArk]

Re: Diagnosing OMS/VRO issue

bump

 

[jegervais]

Re: Diagnosing OMS/VRO issue

787070 is the correct service manual fort a 2000 model Johnson 115 hp, carbureted engine.<br /><br />The 3 questions you asked in your first post, are geared more towards the DI (Direct Injection) model engines, not the carbureted ones.<br /><br />If you look at pg 4-35 you will see the upper portion of the OMS in the bottom of the picture. Its in the center and has the electronic circuit board on the front of it. Page 2-32 also shows a view of it in picture #6 - the technicians fingers are touching the pump. <br /><br />You will need to remove the air silencer box to see these components.<br /><br />-John

 

[SeaArk]

Re: Diagnosing OMS/VRO issue

Thanks John!!!

 

[SeaArk]

Re: Diagnosing OMS/VRO issue

I am going to replace the VRO unit and was wanting some feedback.<br /><br />They say to purchase the zip ties from the dealer to insure that you have air tight connections to the fittings on the VRO pump. Do I need the tool that pulls them down tight and cuts them or can I pull them down with pliers and cut them with dikes ??

 

[seahorse5]

Re: Diagnosing OMS/VRO issue

Do not use the zip-ties on the oil line fittings, just the on the fuel system. The part number is 320107 for the zip-tie.<br /><br />Are you sure the pump is bad? Did you perform the oil consumption test that is listed in the manual, along with the vacuum test for restrictions?