OMC Variable Ratio Oiling System
1985 Johnson/Evinrude 2HP thru V-6 models
The VRO equipped models use a self-contained pump mounted on the powerhead in place of conventional fuel pumps. The V RO pump does not require electrical power. The pump has four hose connections as follows:
| A - Fuel IN | C - Crankcase Pulse Hose |
| B - Oil IN | D - Mixed Fuel OUT |
The VRO pumps oil and fuel, meters the fuel/oil ratio from proximately 50:1 up to approximately 150:1 sensing the engine power output.
The VRO will also pump fuel/oil mixture if the customer does not wish to use the VRO system if there is not sufficient m for the VRO oil tank. II VRO models shipped with "E" and clamp "F" over the oil inlet nipple the lower engine cover. If the VRO tank is not used, the and clamp should not be removed. This will prevent dirt moisture from entering the fuel system.
6.8 L (1.8 gal.) VRO oil tank is shipped with each motor. The oil tank is about the size of battery box and includes hardware for floor mounting. Also included is 3 m (10') oil hose with primer bulb and 3.6 m (12') of electrical wiring for the low oil level warning system. The oil tank is made of translucent corrosive plastic. The oil level be viewed without removing the .
The oil tank has vented "G". There is pickup assembly "H" that has filter and foot valve to keep the oil from draining back from the oil hose. low oil level warning "I" signals when the oil level drops to 1/4 of capacity. This signal is transmitted to the warning horn, which is activated for 1/2 second at
20 second intervals to indicate low oil level.
A cap holder/plug "J" is shipped each motor attached to the fuel "OUT" hose. When the "E" is removed from the oil inlet nipple it should be placed the holder/plug for storage. If the oil hose should have to removed from the oil inlet nipple the should be installed over the oil inlet nipple. The holder/plug is used to plug the oil hose to prevent oil leakage and prevent dirt from entering the oil system.
If the oil hose was removed from the motor, the following items must be completed:
- Purge air from hose before installing
- Lubricant must added to the fuel tank at 50:1 fuel/oil ratio
- Mark the oil level the VRO tank
- Before switching to unmixed gasoline, check to see that level in oil tank has changed
Updated on: Saturday, November 21, 2020