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Vro connections 200hp 1998

I

interd0g

Contributing Member
Wile t/shooting tacho I see gr

Wile t/shooting tacho I see grey tacho feed also goes to vro.
Does this mean that if tacho signal fails oil injection fails?
What is the tacho feed to vro for?
I have read the tech manual but it doesn't say.
 
"thats part of ur warning horn

"thats part of ur warning horn system,that senses rpm pulses,...wont effect vro operation"
 
"Of all the traditional two st

"Of all the traditional two stroke outboards produced worldwide, OMC products have the only automatic lubrication systems with a "no oil flow" alarm. The VRO's electronic circuitry compares the RPM of the engine to the number of pressure pulses from the oil pump piston. As the oil flows into the fuel area, the pressure moves a small piston that actuates a steel pin in the alarm module. The pin's movement is detected electronically and "counted." If the engine revolutions exceed the preprogrammed oil pulse ratios, the warning horn is activated sounding a rapid on and off sequence. Since 1993, the VRO is actually called an oil metering system (OMS). The ratio averages about 60:1, slightly leaner at idle and slightly richer at full throttle. The older pumps idled between 150:1 (prior to 1990) and 100:1 (1990-1992), then richened up to 50:1 as the engine load increased. They are recognized by the brown fuel outlet fitting and/or a wiring harness attached to the alarm module.

The original VRO from 1984 and 1985 had a black fuel outlet fitting and no wiring. OMS pumps have a blue/gray outlet nipple or a blue/gray pulse nipple, or a black fitting held in place by an oval metal bracket and two Torx headed screws. To simplify things just remember that the air motor converts the crankcase pulses to a back and forth motion. Directly connected to the air motor is the fuel pump and the oil pump. The travel of the air motor pumps the fuel and the oil together to the carburetors and the alarm system monitors the oil pressure counts. Just like manually premixing the oil and gas, the VRO (OMS) automatically does the same thing and sends that fuel mixture to the carburetors."
 
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