Re: Johnson VRO system question
If you look into the actual cost of the non-mixing fuel pump (aka premix pump) for your engine, it is amazingly close to the cost of the mixing pump. Probably something like $350 vs $300 street price, $450 vs $400 list. There might be cheaper alternatives you might be able to cobble together though.
I'd like to ditto to what Chris1956 said. The system is good, but d/c'ing it is very easy. Reliability can fail both ways - lack of proper premixing, or system failure. More incidents of improper premixing than actual verified VRO/OMS system failures, imho.
For fun, read this:
http://continuouswave.com/whaler/reference/VRO.html
If you decide to go with the VRO/OMS system in the end, the pump is your major cost (above), but you'll also need the oil tank, which you can easily find used but "like new" on ebay for $75 or less. Make sure you get the proper tank for your engine. The two options are 1995 and earlier or 1996 and later. Has to do with the way the "low oil" alarm is signaled.