Re: 115 vro?
Just converted my 1987 110 over to old style pump. When I was researching how to do it I ran across something from Johnson/OMC. I believe it said they started the VRO system back in 1986.
If your having troubles with it though, I'd advise removal of the VRO and replacement of the fuel pump. Use the old style vacume pump. They apparently knew plenty of folks would be converting their engines. The vacume fitting and pre-drilled holes are on the block, just in front the starter. Easy convert, cheap to, and it will save you all kinds of trouble.