Disconnecting VRO - Any real world experience ?

[Brad1]

Anyone have any real world experience with disconnecting the VRO on an OMC motor?

I have a 16 aluminum boat that has a 1994 60 hp Evinrude and a 2001 9.9 Johnson kicker. The 60hp is a VRO and the 9.9 is pre-mix. The boat does not have a built in fuel tank. I use two separate 6 gallon tanks, one with straight gas for the 60, and one with 50:1 pre-mix for the 9.9. I want to be able to use the same fuel supply for both motors so I disconnected the VRO on the 60. I capped off the oil line and disconnected the wires. I basically followed this procedure: http://www.nitroowners.com/projects/VRO_the_removal.htm

Of course I'm going to run 50:1 pre-mix through it now.

The biggest concern I have is lubrication. I wouldn't expect there to be any problem since I'm going to run pre-mix, but I just thought I'd ask.

[yarcraft91]

Take a look at the break-in instructions for your motor. I expect they call for you to pre-mix gas and oil at 50:1 during break-in. The manual probably also says to keep running 50:1 until you see that oil is being consumed from your oil tank.

One reason for the initial 50:1 mix is to ensure the motor has lubrication just in case the VRO pump was not properly primed. Your manual probably says to use 50:1 pre-mix fuel whenever you break open the line to the oil tank or the VRO pump. Again, the reason is to ensure the motor is lubricated in case the VRO isn't delivering oil.

That's a long way of telling you that pre-mixing the fuel/oil at 50:1 for your 60 horse will work just fine. The VRO was probably delivering that mixture when it was working (mine has averaged out to 50:1 over the past 17 years).

[southerncomfort1]

Anyone have any real world experience with disconnecting the VRO on an OMC motor?

I have a 16 aluminum boat that has a 1994 60 hp Evinrude and a 2001 9.9 Johnson kicker. The 60hp is a VRO and the 9.9 is pre-mix. The boat does not have a built in fuel tank. I use two separate 6 gallon tanks, one with straight gas for the 60, and one with 50:1 pre-mix for the 9.9. I want to be able to use the same fuel supply for both motors so I disconnected the VRO on the 60. I capped off the oil line and disconnected the wires. I basically followed this procedure: http://www.nitroowners.com/projects/VRO_the_removal.htm

Of course I'm going to run 50:1 pre-mix through it now.

The biggest concern I have is lubrication. I wouldn't expect there to be any problem since I'm going to run pre-mix, but I just thought I'd ask.

My motor has the VRO disconnected.As you said you have to manually mix the oil each time you add fuel.Sure a little pain but worth the sound mind and comfort knowing your motor is for sure getting lubed with the bad history rap with the VRO's from the 90's. Just don't forget to mix it and you will be good to go.I believe some people replace the fuel pump instead of capping the oil side off not sure which way is preferred but ironically yesterday my motor was not running right after I got home I found my fuel pump is leaking so hopefully that is what was affecting my motor and I will try to get that changed this week.

[yarcraft91]

I agree the VRO system has a bad history rap, but I have no complaints about it. The VRO in my 1991 Johnson 120 has worked fine since new. The one time I thought it was over-oiling the motor, I found this article. For other VRO owners having trouble with their units, I recommend this quick read:

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

After reading, I went over my motor and found a broken clamp on the suction side of the fuel pump. I replaced it and- sure enough- over-oiling problem solved. I also installed the blue pulse limiter to replace the OEM black fitting.

Those who choose to defeat the VRO and pre-mix their fuel will certainly have reliable lubrication. I'll stick with the convenience of the VRO as long as it keeps working.

[Brad1]

Just to clarify my original post, I'm not disconnecting my VRO because I don't trust it. I'm eliminating it because it is more of a pain with this particular boat / motor configuration, having to have two separate fuel supplies. If my 9.9 was oil injected, I wouldn't be eliminating the VRO on the 60. But having to have two separate tanks, and each only being able to serve one (and only one) motor is a PITA.

[T Mac]

Anyone have any real world experience with disconnecting the VRO on an OMC motor?

I have a 16 aluminum boat that has a 1994 60 hp Evinrude and a 2001 9.9 Johnson kicker. The 60hp is a VRO and the 9.9 is pre-mix. The boat does not have a built in fuel tank. I use two separate 6 gallon tanks, one with straight gas for the 60, and one with 50:1 pre-mix for the 9.9. I want to be able to use the same fuel supply for both motors so I disconnected the VRO on the 60. I capped off the oil line and disconnected the wires. I basically followed this procedure: http://www.nitroowners.com/projects/VRO_the_removal.htm

Of course I'm going to run 50:1 pre-mix through it now.

The biggest concern I have is lubrication. I wouldn't expect there to be any problem since I'm going to run pre-mix, but I just thought I'd ask.

I had a 60 Ev on a 1990 Alumacraft (tiller).
Those VROs loved to malfunction and mine did. No alarm sounded and I burned up the engine.
When I got the new replacement powerhead.... I went to mixed gas.
No more problems.


Dam straight, Brad... I wouldn't trust it either.
As an old Evinrude dealer we saw a lot of Mexican made VROs fail.

[Miami Vice]

By disconnecting the VRO and just running a 50:1 ratio, the worst that can happen is if you do a lot of trolling, you can foul up the spark plugs sooner. Replacing spark plugs is cheap and easy so I wouldn't worry about running 50:1 ratio.
Suzuki was the first company to mass produce oil injection in their 2 stroke motorcycles. That same technology used in 2 stroke outboards by Suzuki, Yamaha and Merc.
OMC didn't want to pay for any licensing agreements using this dependable Japanese technology, so they decided to reinvent the wheel and came out with VRO. Here in Miami Beach a number of large outboards burnt up their powerheads because of malfunctions in the VRO system. Lot of things caused the demise of OMC, and VRO was one of them.
Miami Vice

[southerncomfort1]

By disconnecting the VRO and just running a 50:1 ratio, the worst that can happen is if you do a lot of trolling, you can foul up the spark plugs sooner. Replacing spark plugs is cheap and easy so I wouldn't worry about running 50:1 ratio.
Suzuki was the first company to mass produce oil injection in their 2 stroke motorcycles. That same technology used in 2 stroke outboards by Suzuki, Yamaha and Merc.
OMC didn't want to pay for any licensing agreements using this dependable Japanese technology, so they decided to reinvent the wheel and came out with VRO. Here in Miami Beach a number of large outboards burnt up their powerheads because of malfunctions in the VRO system. Lot of things caused the demise of OMC, and VRO was one of them.
Miami Vice

Actually I had a first time problem this weekend.What happened I filled boat full with fuel then added my oil.(51 oz) then took off to the lake.I think what happen was the fuel and oil did not mix well since there was no room in the tank to splash around to mix up and I sucked up a big glob of oil.Boat ran rough.Changed filter and plugs and back to running smooth again....I think what I will do next time is add fuel stop at point where I know I can still add a few more gal. then take a gas can add 1 or 2 gal then my oil to that then shake and mix it good then pour it in the boat or just not fill it up all the way to allow room for the fuel to splash around to mix.

[yarcraft91]

I think what I will do next time is add fuel stop at point where I know I can still add a few more gal. then take a gas can add 1 or 2 gal then my oil to that then shake and mix it good then pour it in the boat or just not fill it up all the way to allow room for the fuel to splash around to mix.

Once you have un- or poorly-mixed fuel/oil in the tank, it's tough to get it completely mixed- the bigger the tank the tougher the mixing (years of experience with chemical engineering here). Sloshing around in a near-full tank while trailering the boat doesn't really do it. Ideally, mix all the gas and oil at 50:1 in 5 gallon cans, then pour the pre-mix into the tank. If that's more trouble than you want, pour the oil into the tank first, then add the gas. Yeah, you can't always know exactly how much gas the tank will hold, but you should know if it will take 10 gallons or 15 or 20, so at least pour in enough oil for the amount of gas you know you can add and top off with pre-mix. In cold weather, it's particularly tough to mix the oil and gas, so mixing in an external can is best then.

[southerncomfort1]

That certainly is an option.Get about 4 of the 5gal cans keep premixed in them at home ready to put in boat as needed before leaving.That way I could dump at least 20 gal in if low and going somewhere I need plenty of fuel.Just might have to consider that after this weekend....