Somebody please explain what VRO is/does?

angus63

Captain
Joined
May 20, 2002
Messages
3,726
Re: Somebody please explain what VRO is/does?

VRO=variable ratio oiling<br />It is a metering pump that controls the gasoline/oil ratio delivered to your motor (simply stated).
 

MGuckin

Senior Chief Petty Officer
Joined
Jun 10, 2001
Messages
760
Re: Somebody please explain what VRO is/does?

All 2 strokes require oil to be mixed with gas for lubrication purposes. On older motors, and some newer by choice, you would mix 2 stroke oil in with your gas at a specified ratio. Modern motors use a ratio of 50 parts gas to 1 part oil.<br />VRO takes the place of having to mix your fuel. It is a self contained oil tank that, when working properly, will mix the required amount oil with your gas without your intervention other than keeping oil in the reservoir.
 

c11yll

Cadet
Joined
May 18, 2002
Messages
27
Re: Somebody please explain what VRO is/does?

Thanks a lot guys.<br />I was wondering why people disconnect the VRO unit, is it unreliable or something??
 
D

DJ

Guest
Re: Somebody please explain what VRO is/does?

c11yll,<br /><br />The VRO system is one of the most maligned mechanical devices ever conceived by man. It has been blamed for everything from sunspots to hangnails.<br /><br />Thruth is, most engine failures that are attributed to no or low lubrication usually effect one cylinder. These concerns are caused by clogged carb. jets, not the VRO system. The VRO systrem CANNOT discriminate which cylinders get oil and which do not. The system injects oil into the fuel BEFORE it gets to the carburetors.<br /><br />Have VRO systems failed-sure they have, so have water pumps and other components that can cause catastrophic failure.<br /><br />The VRO system typically is a hands off feature that most boat owners are unaware of the fact that the system does require maintenance.<br /><br />The maintenace is very basic and generally includes a thotough cleaning of the tank, replacement of the filter sock and a check of all the associated delivery lines-no big deal.<br /><br />I have never had a moments trouble with any of them I have owned and would have another any day.
 

evin300

Petty Officer 1st Class
Joined
Jun 4, 2001
Messages
384
Re: Somebody please explain what VRO is/does?

Good one djohns! my sentiment exactly.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Somebody please explain what VRO is/does?

Very good djohns! <br /><br />I have seen motors with water in all 6 cylinders and the cause of failure is listed as "VRO failure". The VRO pump didn't fail.....it was pumping what was in the tank. Water.<br /><br />The only thing I could add is that they have not been "variable" for quite a while. They are now refered to as "oil pumps" because they are 50:1 at all rpm's.<br /><br />Good post djohns!
 

c11yll

Cadet
Joined
May 18, 2002
Messages
27
Re: Somebody please explain what VRO is/does?

That's just the answer i'm looking for, my confidence has now been restored. I was thinking for a while there i might have purchased a real trouble maker, there seems to be quite a few people on this site who have/are disconnecting their vro's. With me being new to boating i was rather worried!!<br />Thanks for taking the time to reply y'all!!
 

yrag

Cadet
Joined
May 24, 2002
Messages
23
Re: Somebody please explain what VRO is/does?

My Vro just went, But I guess after 17 years thats ok.I Put a new one on without a second thought. (1985 175 Johnson)
 

neptune202

Cadet
Joined
Feb 24, 2002
Messages
25
Re: Somebody please explain what VRO is/does?

The VRO on my 94 Evinrude 140 has just given up. A re-man replacement is only $100 from DFI. Any accessory component on anything, car, motorcycle, truck etc. is subject to failure and would cost as much. I'm keeping the VRO operational.
 

neptune202

Cadet
Joined
Feb 24, 2002
Messages
25
Re: Somebody please explain what VRO is/does?

PS- to correct an earlier post about the "50 to 1" ratio, gas is 50 to 1 over oil. That is to say 1 gallon of oil (outboard motor oil) to 50 gallons of gasoline.
 

c11yll

Cadet
Joined
May 18, 2002
Messages
27
Re: Somebody please explain what VRO is/does?

can't wait for the manual to arrive, i'm just bustin to get busy on this thing!
 

MGuckin

Senior Chief Petty Officer
Joined
Jun 10, 2001
Messages
760
Re: Somebody please explain what VRO is/does?

neptune202,<br />And I just mixed 50 gallons of oil in a gallon of gas. <br /> :D <br />I edited my typo.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: Somebody please explain what VRO is/does?

For an indepth story on the misconceptions, upgrades, and history of the VRO, get a back issue of either the Jan 2000 Bass and Walleye Boats or the Feb. issue of Trailer Boats.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Somebody please explain what VRO is/does?

Double check you warning system to make sure it works. I've also seen a lot of failures because the horn did not work properly.<br /><br />Good luck!
 

keepiton2

Cadet
Joined
May 27, 2002
Messages
18
Re: Somebody please explain what VRO is/does?

i just purchased/installed a new vro pump on my 1989 110 v4 johnson. the salesman sold me new plugs too and said now the new pump gives the motor a 60 to 1 ratio so i had to change the plugs to a plug that would take more heat. just a little tidbit of info...you folks have been a huge help for me in the last few weeks !!!!
 
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