I wouldn't bother ... I actually have a new OMS (Oil Metering System, no longer called VRO for Variable Ratio Oiling) pump on hand. It actually really is just a fuel pump with the oil system built in, driven by rotations of the crankshaft. I haven't even bothered to replace the fuelpump that's on the motor. You'd need to modify your wiring too, as newer systems are 4-wire and your existing harness is 3-wire, so you'd need to pull the purple wire from somewhere else off the harness, with 'purple' wires being powered only when the ignition is turned on.
Pre-mixing can be a tiny bit of a pain, but here's what I do, since I buy my oil in bulk gallons, and $15/gallon Penzoil semi-synthetic (Walmart) is good enough for her ('98 OMC 225hp), but I will run Walmart's 'Pwer Tech' dino oil TC-W3 when I know I'll be on long toona runs, like ~80+ miles in a day. And for the record (confirmed by NMMA) either Merc, Yam, or OMC/Bomb makes that dino oil for Walmart.
OK, back to what I do
. I ferry my own fuel in 5-gal jerry cans (have 4), so I'll save used oil containers and make some up with enough oil in them for 5, 10 or 20 gallons, or more as I'll make up 2-3 or more of each size. These are "pre-made up", so if I'm only adding 10-gallons, I just tip and dump an oil container marked "10" into the funnel (the funnel holds the oil container inside it) while I add the fuel into the rest of the funnel. Slick funnel! Just have never seen another one like it. This 'pre-bottling' method saves me time when fueling, saves hassel, eliminates any mess or measuring when I'd rather be fishing. Just a few minutes [or 1-beer in Megabyte time
] every other weekend or so gives me more than enough oil all bottled up ahead of time to just head out and go!
As is, your motor will smoke a tad more without OMS hooked up, but I don't see the co$t being worth the hassel and fuss, but that's me ... and I'm a cheap bast#$d. Oh, and even though I know it's new, I won't sell you or anyone else my OMS pump. And if it were me buying ... I'd only buy new. Remember, you also need the oil tank, hold-down kit, oil line, oil harness (sends signals for low and NO oil) and need to route all and rig them through the grommet on the front of the motor. Pain in the arse that rigging is ... and those grommets aren't cheap! And if you do this, you MUST check those alarms before using the boat! Meaning, run at least on some pre-mix with oil BEFORE totally eliminating the pre-mix.
Just my opine ... do like me and save for a new Suzi 4-S
!
