1985 Evenrude 50 HP VRO Fuel Mix

Byrdman":zyfztq2l said:
Need help with the fuel mix ratio of an old 1985 Evenrude 50hp VRO motor. Clues anyone?
Byrdman
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VRO stands for Variable Ratio Oiling and is a system designed to mix the oil with the fuel automatically. In general, the fuel:oil ratio varies from 150:1 to 50:1 with the latter at wide open throttle. Some report problems with the earlier systems and just use a 50:1 pre-mix. This is a bit more oil than you need at idle but is (from what I could find on the net) a fairly safe level.

Maybe Gary (gflr) can chime in - he's a mechanic...

Roger on the SeaDNA
 
"Former mechanic" is more correct and that on cars! But 50:1 is what we used to run on my old Crestliner with the 115 Merc growing up. And is what I run on my '74 Johnson 25hp.
 
Patrick, From what I've read on other sites It's not uncommon for the early VRO pumps to fail. A Lot of guys just bypass / disconnect them and go with a straight 50:1 premix. My 84 Evinrude is pre VRO and uses a 50:1 mix.
Norm
 
Patrick,

I was an Evinrude mechanic during the VRO years. If you are going to put 50-1 mix in the tank, be sure to cap off the oil inlet fitting. It is located near the fuel inlet on the motor pan.

After the oil inlet is capped off, you can use mixed fuel in the tank just like a non-VRO motor.

Hope this helps.
 
While it's true, most of the early VRO's have failed by now, most did not fail "to the bad". The later/current pumps do not vary the oil ratio, but are very reliable. You may want to consider replacement.(if it hasn't been done already)

A two stroke in good condition will really run quite a while, even at idle, without fouling plugs. Most fouling problems are actually misdiagnosed as oil fouling when in fact it's usually caused by poor engine condition(read: poor piston to cylinder wall tolerance)

I have reluctantly replaced many 50hp Johnsons,(dozens) because the owners believed it was a "2 stroke" problem... Only to overhaul these engines to be sold for use by the "Dock installers" and they would idle(dead idle, in gear) for hours on end with no ill effects.
 
My 1987 90hp VFO Johnson has 400 hours and has never missed a beat. The only thing that has been done is change the plugs every two or three years, and lower unit oil every year. I do not troll with it .

I would like to get a new Johnson 2 stroke or 4 stroke of some kind but its hard to give up a very good engine and convince the keeper of the checkbook that I need $8,000 buck's.

C-Otter
 
My 1987 90hp VFO Johnson has 400 hours and has never missed a beat. The only thing that has been done is change the plugs every two or three years, and lower unit oil every year. I do not troll with it .
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Me too except, 1) 1989 70hp, 2) 1600+ hours, 3) I troll for hours on end @ buoy 10
 
I got 600 hours out of an '87 Evinrude 90 before trading it in on a 2005 Yamaha 90 EFI. Somebody's still running it. No oil pump problems. But the difference in engines is more like 35 years of technical progress instead of 18! Light years of difference! Joe.
 
Larry H: Thanks... That could be what some of the "gagetry" is up around the face of the motor with what simply looked to me as a new uninformed owner of some type of double fuel line set up... Kinda did a big ol hummmm, but was loosing day light hours, it started, it ran... so I took her drove out. Should get some time on the water with her on Friday and will take a couple of pics of what is there. I really appreciate all the feedback.
 
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