The Sinking Of The OutBoard Marine Corporation -

[DanUmbarger]

Was it the plastic housings and orings on the push in fittings that failed or was it the diaphragms? Seems that in most cases it was the oil side of the pumps that went bad allowing for disconnecting the oil system and just mixing oil and gas. In any case the VRO systems they had were atrocious!!

I talked to to an ex OMC engineer who went to work for Yamaha. He held the very first VRO pump in his hand in 1982. It was all aluminum with thread in fittings. By the time it went into production it was made of minlon plastic with push in fittings. These are the type of decisions that help sink them.

[powerabout]

I talked to to an ex OMC engineer who went to work for Yamaha. He held the very first VRO pump in his hand in 1982. It was all aluminum with thread in fittings. By the time it went into production it was made of minlon plastic with push in fittings. These are the type of decisions that help sink them.

There are a few photos of that.

[Revenge22]

Question on the VRO/OMS pumps: Lets say you are at a nice idle for 10 minutes making your way out the channel obn your sweet 200 Vindicator. Because VRO mixes the oil BEFORE the intake manifold (unlike Suzuki and Yamaha that directly shoot it into the crank case. and Suzuki used crank case pressure to ATOMIZE the oil spray) and into the carb bowl, the mixture is now lean. in the beginning it was 150:1. Now you hit the gas. what gets sucked into the motor for a full 15 seconds or so? lean mix. in reverse, the motor will load up like crazy.

[DanUmbarger]

You are correct about the oil being discharged into the fuel stream before the carbs....not sure how the 150:1 oil mix would affect a Hi Performance engine at WOT but obviously not too bad because they had it for years. The 50:1 at an idle is a no brainer...been running 50:1 for years. Suzuki had multi port oil injection for years but did eventually go to a single port injection pumped in just before the fuel pump which I didn't care for for the reasons your asking about.

Question on the VRO/OMS pumps: Lets say you are at a nice idle for 10 minutes making your way out the channel obn your sweet 200 Vindicator. Because VRO mixes the oil BEFORE the intake manifold (unlike Suzuki and Yamaha that directly shoot it into the crank case. and Suzuki used crank case pressure to ATOMIZE the oil spray) and into the carb bowl, the mixture is now lean. in the beginning it was 150:1. Now you hit the gas. what gets sucked into the motor for a full 15 seconds or so? lean mix. in reverse, the motor will load up like crazy.

[PanRonnie]

Question on the VRO/OMS pumps: Lets say you are at a nice idle for 10 minutes making your way out the channel obn your sweet 200 Vindicator. Because VRO mixes the oil BEFORE the intake manifold (unlike Suzuki and Yamaha that directly shoot it into the crank case. and Suzuki used crank case pressure to ATOMIZE the oil spray) and into the carb bowl, the mixture is now lean. in the beginning it was 150:1. Now you hit the gas. what gets sucked into the motor for a full 15 seconds or so? lean mix. in reverse, the motor will load up like crazy.

For performance boating they adviced 50 to 1 in the tank on top of the VRO mixture
It is mentioned in the manuals

[Revenge22]

no im saying the TRANISTION period when its lean in the carb bowl, then you give it gas. my point is it cannot instantly change to the proper (richer) fuel mix. this is probably why they went to 100:1 later on, which is rich enough .

[Revenge22]

yeah which completely negates the need for an oil pump! I actually never heard that from the bulletins, but certainly possible. my 2.6gt of course does not even have an oil pump. tells you something, although it was made in late 83'.

[Mark Poole ModVP]

The VRO idea was just a way of putting oil injection on the engine without having to do any machining or retooling. Adding the pulse limiters and rubber bushed mount brackets were just ways of trying to stop the problems. Many of the pumps warped and cracked which made them leak or suck air. Another butt kicking problem that we discovered the hard way was if the cylinder that pulsed the pump would lose pressure from that piston having any scoring/scuffing it would not drive the pump at higher speeds because of a loss of crankcase pressure on the down stroke. The cylinder might still have good compression but still have enough damage that it would not pulse the pump enough to keep the boat on plane. That engine had stumped 3 other OMC shops and I was quite proud of myself for finding that problem as I was 23 years old at the time.

[DanUmbarger]

I knew what you were saying it just didn't come out correctly on my end...I was just thinking out loud how much damage would be done running the higher HP motors at 150:1 until the carbs were filled with the 50:1.....they used the VRO for years. I personally have switch many motors over to the manual mixing system....using the VRO for the fuel pump or installing a completely separate fuel pump.

no im saying the TRANISTION period when its lean in the carb bowl, then you give it gas. my point is it cannot instantly change to the proper (richer) fuel mix. this is probably why they went to 100:1 later on, which is rich enough .

[Revenge22]

Never thought of it that way! I guess its another way of saying always test fuel pump pressure if it keeps falling on its face and you cannot figure out why. That seems to be the cause of a few v4 and v6 looper running issues i've had, although a time or two it was the pump itself so switched to standard fuel-only pumps. I agree can drive you nuts but its ALWAYS something obvious like that.

[Revenge22]

yea just something i was thinking about. in reality, it probably takes fuel quite quickly especially on the loopers with the shallow small bowls. come to think of it, thats probably why they made them that way so the oil mix become richer faster. go figure.

[FUJIMO]

[FUJIMO]

...remnants of omc/bombardier. this guy cracks me up... https://youtu.be/A89F_4miTEc?si=SUDpHwaMlbeYJaPi