[bruteforce]

I have a 1996 Evinrude 150 V6 intruder. I purchased the motor used and was told by the previous owner that the motor wasn’t drawing 2-stroke from the reservoir and that I must pre-mix at 1:50 ratio (which I've been doing) and keep enough oil in the reservoir to prevent the reservoir low oil alarm from going off. I have only been out a handful of times and used less than 3 tanks of fuel. The motor runs like a dream – no hesitation on take-off and smooth through all rev ranges. On my last trip the low oil alarm went off indicating that the motor is drawing 2-stroke from the reservoir. I have a few questions.

How can I tell if my motor is drawing sufficient oil from the reservoir? (I obviously am reluctant to stop premixing if there is potential to damage my motor due insufficient lubricant.)

Does the motor draw a standard 1:50 ratio from the reservoir or does it adjust according to revs, etc? In other words, if I measure how much oil versus fuel it’s using when idling on muffs on the slipway – will this be an indication of how much it will use under load on the dam?

I put in new sparkplugs when I purchased it and there is already a bit of carbon build up on them. Is this a result of too much 2-stroke?

Can I damage my motor (other than a bit of smoking at start-up) if I’m pre-mixing at 1:50 ratio and its still drawing lubricant from the reservoir?

Is it advisable to add any additives to prevent or remove carbon build-up and if so, how often should this be done?

Any advice would be much appreciated.

[tashasdaddy]

it is advisable to add seafoam to your fuel. you have an OMS pump. constant rate of 50:1 mixing. other than the smoke, the mixing will not hurt. you can check your oil usage, and verify the OMS is working. or you can convert it to straight premix, and know it is getting proper fuel:oil ratio.


conversion to premix is easy.
VRO conversion w/ pump still working

if the fuel side on your Pump is still working it is very simple. unplug the 2 line harness going to the oil tank, unplug the 3 or 4 wire harness, going to the Vro pump. cut and cap the oil line going into the motor. add oil to fuel tank, mix well, then remove fuel line at top carb, catching gas in a container, pump the fuel line bulb until you get premixed gas to the carb. you can tell as it will change color. put line back on carb, and go boating.

[Chris1956]

Brute, It is easy to verify the OMS pump is working properly. Simply fill the oil tank to the top. Now run a tank or two of premix fuel. Now refill the Oil tank to the top and note how much oil it takes. My '98 Johnny 150V6 runs at about 60::1, so you would see about 13oz oil used/six gallons of fuel.

If it is lower than that, the OMS pump is likely faulty. Sometimes they can be rebuilt, to some extent.

[bktheking]

Disable the VRO and run premix, can't count how many people grenaded their ten thousand dollar motors cause the VRO pump died, silly design IMO. Guess it's a good way to insure motor sales Or run it and take your chances, my motor is an 83, even if it had vro that crap would have been removed soon I bought the boat.

[Faztbullet]

Follow Chris's instructions and add a little seafoam to fuel , then switch to the XD oil and you wont need seafoam again.