Evinrude VRO

[dish]

Having a lot of dramas with vRO on 1997 150 ocean pro.It justy wont pump fuel.Pumps plenty of oil into carbs.Pumps fuel if i squeeze bulb or have fuel above pump.Checked everything,air leak,blockage,compression,antisyphon,pulse fitting.No air bulbbles going to pump with clear hose connected.The bulb stays primed it just wont pick up the fuel.Has anyone had any success with the rebuild kit for the fuel side of VRO,and if the vapour pump is not working would that stop the pump from picking up fuel?Not reaaly sure what the vapour pump does except give you a fuel restriction warning through the sensor.Some one must have an idea????

 

[seahorse5]

Re: Evinrude VRO

If it will not pump fuel, the air motor diaphragm or check valves may be bad, or the fuel pump diaphragm may have a hole in it. It has to be taken apart to inspect or use the pressure-vacuum tests from the service manual.

http://continuouswave.com/whaler/reference/VRO.html

 

[Chris1956]

Re: Evinrude VRO

There is a vacuum sensor on the fuel line. This gives the Check Engine (fuel restriction) alarm. You might inspect the vapor pump. It has a float, inlet needle and seat inside it. Perhaps it has a restriction? Perhaps the cover gasket is leaking air?

 

[dish]

Re: Evinrude VRO

Thanks for replying.I have pulled the VRO apart and it looked fine,no holes or air leaks.I even put the pump on my brothers 70hp VRO johnson and it worked????? Does the vapour pump affect the fuel pump side of the vro .It is pumping oil into the carbies but not fuel.It will run when you prime it until the fuel and oil mix just turns into straight oil then smokes like you wouldnt believe and snuffs out.THe vapour pump has me thinking,just need to know if it directly affects the fuel side of the pump.I did pull it apart and checked float and needle.Looked perfect.Any one have an idea about this.Dont want to buy a new pump if i dont need one.PLEASE it is driving me crazy.

 

[Chris1956]

Re: Evinrude VRO

The vapor pump only has gasoline in it. Why not concentrate there?

 

[dish]

Re: Evinrude VRO

Not sure what you mean by only gas.Do you mean gas and oil mix or just gas.

 

[Chris1956]

Re: Evinrude VRO

The vapor pump is upstream of the OMS pump. It has only gasoline in it.

 

[dish]

Re: Evinrude VRO

So fuel gets drawn from the tank by the vapour pump then goes to the oms pump to mix with oil before pumping to the carbs.Is that right.

 

[dish]

Re: Evinrude VRO

Does anyone know it the vapour pump on a 1997 150 evinrude ocean pro directly affects the oms pump.Meaning if vapour pump fails will that stop the oms pump from pumping fuel?

 

[Chris1956]

Re: Evinrude VRO

Dish, I asked that question on this forum before. I did not get an answer that I understood.

I have never had my vapor pump apart, however, the service manual clearly shows gravity feed of gasoline from the vapor pump to the OMS pump. That leads me to believe the vapor pump must assist the OMS to pull gas from the tank, and must be air tight. One day I expect to have the issue you have now. I would like to be prepared to solve it.

 

[clanton]

Re: Evinrude VRO

Your fuel pump is sucking air, or the pump is bad. Pump pumps fuel/oil to the vaper seperator, then to the carbs. Oil and fuel mixed inside the pump. I will try to post photo fo fuel system from manual tomorrow. I could be wrong about this.

 

[dish]

Re: Evinrude VRO

I hope not mate.I think your right about the vapour pump.It must help the whole fuel line stay primed,so it has to be air tight.You would think someone would know more about it.I am borrowing a working OMS pump on saturday so that will tell me once and for all the condition of mine.If that doesnt work the problem can only be the vapour pump or that assembly.I will definetly post my results when i solve this pain in the arse.

 

[clanton]

Re: Evinrude VRO

I think the pump pumps fuel, to vaper seperator, when VS is full and the float closes, then fuel goes to carbuators.

 

[dish]

Re: Evinrude VRO

I wonder what the vapour pump does then?

 

[TLL]

Re: Evinrude VRO

Fuel passes through the fuel filter, goes into the vapor seperator, flows to the vro pump, back to a distribution manifold attached to the vapor seperator, and then to the carbs. The vapor seperator is a vacuum driven pump on top of the vapor seperator that sucks the fuel vapor out of the seperator and sends it to the bearings. It does not assist the vapor seperator in filling and doesn't pump fuel. It just assures that the OMS pump gets a liquid supply of fuel. Since it is on the suction side of the fuel system, I suppose if it allowed air to enter the seperator, it could cause the OMS pump not to be able to suck fuel. You could check this by plugging the outlet hose and see if the OMS pump would then suck fuel. My gut feeling is that there is something wrong with the fuel pump part of the OMS pump. If the diaphram looks good, one of the check valves in the pump maybe stuck. The air motor part is functioning as it is pumping oil.

 

[dish]

Re: Evinrude VRO

Good stuff,finely a discription of the vapour pump.I will block the vapour pump and see what happens.The wierd thing is that the oms pump worked on my brothers 70hp johnno.It has higher compression though and only has to supply three cylinders.Not sure if that makes any difference.There are two check valves near the pulse fitting i was thinking if one of those were bad it wouldnt even pump oil?Has to be the pump.See what happens on saturday when i connect a known working oms pump.

 

[Chris1956]

Re: Evinrude VRO

Dish, Vapor pumps are relatively new. Does your brother's motor even have one?

 

[seahorse5]

Re: Evinrude VRO

Dish, Vapor pumps are relatively new.

Johnson and Evinrude have used them since 1991, almost 20 years. I wouldn't consider that as relatively new.

 

[clanton]

Re: Evinrude VRO

150 60 degree hose routing. If the small vapor pump is bad, the VRO pump will suck air. Look at the diagram, the vapor pump outlet goes to the upper and lower main bearings. A fuel restriction could also be in the VS housing. Hope this helps, I may have learned something myself.

 

[dish]

Re: Evinrude VRO

No my brothers motor doesnt have a vapour pump.The hose routing diagrame is interesting.I think i will try and disconnect or bypass the vapour pump and see if the oms will then pick up fuel.Mate if it turns out to be just the vapour pump thats causing this i hope we all bloody learn something.I will post my results.