Remove VRO???

Discussion in 'Outboards' started by gadget300, Apr 13, 2012.

  1. CDK
    Joined: Aug 2007
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    Location: Adriatic sea

    CDK retired engineer

    No need to argue about sense or nonsense concerning oil injection, when properly designed it can be very reliable and uses far less oil than premixed fuel.
    But the many posts on forums about engine damage from lack of lubrication are nearly all related to the Johnson VRO, so there is obviously something wrong with it.

    If you want to minimize fuel and oil cost, 4 stroke should be first choice, but it is expensive. For an engine with less than 50 hours in a year, a 2 stroke is more economical and without the VRO, less can go wrong.
  2. villacose
    Joined: Dec 2011
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    Location: Houston, TX

    villacose Junior Member

    every oil injection system i have ever heard of is bad. even Yamaha, my favorite engines ever. look on ebay, there are a lot of GP1300 Waverunners for sale with blown engines, and why? the oil injection. seadoo PWC, skidoo snowmachines, Polaris, you name it, 2 stroke engines should NOT have oil injection. it does not work, period.

    Johnson's used to be the best engines out there. but you cannot run a 2 stroke engine at 100/1 oil.

    I use premix even on my 4 stroke engines, and if you think that is silly, look up the long-winded Mercury report on gas/oil ratio as relates to HP. the more oil the more the horsepower. and Mercury, IMO, are the worst engines, I wouldn't have one, but they did extensive research on gas and oil in a variety of engines.
  3. WestVanHan
    Joined: Aug 2009
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    WestVanHan Not a Senior Member

    Did that..didn't find a single one,just a few running units and the usual parts and rebuild kits.

    That's odd,in the 30 odd years of my whole life in snowmobiling the Rockies and Monashees,and having many friends doing so, I recall one issue where it was dumping in too much oil.

    I had several Sea Doos,never had a problem..and I'd bet if one spent the time browsing the forums the problems would date back to fairly old and well (ab)used machines.
    Most faults trace back to inoperative low oil lights and/or small cracks in the tanks leaking the oil out.
    A friend converted to mix,but then went back to pump as he had more power.

    If you don't like it..fine.But saying "it does not work,period" is a bit much.
  4. tunnels

    tunnels Previous Member

    Got a yamaha 115 vee 4 and the oil injection is great . never given any problems and i sometimes wonder its its going till i hear the oil transfer pump going now and then , plus a puff of blue smoke on start up Have sucked the bottom of the two tanks a couple of times and the tank on the motor got a couple of drops of water out of it . just use the sucked oil in the 2 stroke mower it loves it !!. . :p
  5. Frosty

    Frosty Previous Member

    Of coarse they are great, they were designed by far cleverer people than anyone here. Dont mess wiht it and it will give years of perfect injection just when the motor needs it at full power and little at idle when it doesnt.

    American iron may not run on 100-1 but Japanese technology can.
  6. tunnels

    tunnels Previous Member

    frosty change your avatar !! its gross !!!:eek:
  7. tunnels

    tunnels Previous Member

    Who said that ??

    So putting things into true prospective the Americans are way behind and not envromentally friendly ??:eek:
  8. Frosty

    Frosty Previous Member


    All I can says is all I knows. Ive never seen blown engines with these systems and I live in a country where 2 stroke engines are by the millions.

    Although not many 2 strokes any more except me.

    Hundreds upon hundreds of Yamaha engines in the 150Hp range take tourists para sailing or to outer islands dont have trouble either.

    Im serious on the hundreds ,--maybe a thousand.
  9. kerosene
    Joined: Jul 2006
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    Location: finland

    kerosene Senior Member

    there are many motorcycle engine designs that will not work right with injection removed.
    Premix will not lubricate certain spots that oil injection would. I do not know out boards.

    bike related discussion that might be somewhat relevant:
  10. Jimboat
    Joined: Feb 2002
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    Location: Canada

    Jimboat Senior Member

    Brendan's history is correct. Many of the blown engine cases seen, have been due to failed VRO. Most experienced engine rebuilders will remove the VRO when they rebuild your engine. Their experience tells them that the elimination of this chance of failure is worth the inconvenience of hand-mixing oil.
  11. Frosty

    Frosty Previous Member

    VRO injects fuel as it needs it,--little at idle --max at full RPM.

    Mixing does not meet these accurate rates of injection for clean running emission engines. Smokey idle is neither good for the engine -plugs or environment.

    It must be understandable that for racing applications where full on is required all the time then VRO is redundant.

    Destruction is probably the wrong word, piston to cylinder pick up / seizure would be the first step in failure.
  12. whitepointer23

    whitepointer23 Previous Member

    the old vro's were prone to failure frosty, thats omc not all other brands. i think you mean't it injects oil not fuel.
  13. villacose
    Joined: Dec 2011
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    Location: Houston, TX

    villacose Junior Member

    There is a study floating around by Mercury that talks about horsepower as it relates to premix ratio, and they found that the more oil the more horsepower. They tested all the way down to 16/1.

    I wouldn't trust an oil injection system no matter the brand. On Ski doo snowmachines, I knew a lot of people who had ruined engines because of vibration affecting the oil pump. Yamaha GP model waverunners (1200 and 1300) are very prone to engine failure because of the oil injection.

    I bought a new Johnson 8hp once and the owners manual said to mix the oil at 100 to 1. I ignored that as insanity and that engine ran great until a friend dumped my canoe and it sank to the bottom of the river.

    If I ever did trust an oil injection system, I would still premix my fuel with a minimum amount of oil anyway, like 60/1. I even premix a little oil into my truck every time I fill up.

  14. Jimboat
    Joined: Feb 2002
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    Jimboat Senior Member

    An error in mixing is probably unlikely. There is also usually gas/oil mix in the tank when you add new (hopefully mixed) fuel. The major reason for circumventing the auto oil system (VRO) is that the consequences of a pump failure are catastrophic engine failure.
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