1988 Johnson 40hp VRO

Discussion in 'Bubba's Outboards' started by JohnnyRuuDe, Feb 18, 2009.

  1. JohnnyRuuDe

    JohnnyRuuDe New Member

    Messages:
    14
    State:
    vermont
    Any idea what kind of charging voltage I should be getting from this engine, I'd like to check it out? -Thanks --lewis
     
  2. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    when the engen is NOT runing=12v
    when engine IS runing over 2000 rpms = 14.5v
     

  3. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Some will charge a little over thirteen and some at 14. It depends op a lot of factors on that motor at the time. Do not pull the cable off the battery with the motor running to see if its charging that will fry you recitfier or voltage regulator.
     
  4. larry d. grady

    larry d. grady Member

    Messages:
    331
    State:
    north caro
    don't worry about the voltage to much ,worry about the vro
     
  5. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    Yea on the VRO. Up until about 1989 the VRO system wasn't all that good.
     
  6. JohnnyRuuDe

    JohnnyRuuDe New Member

    Messages:
    14
    State:
    vermont
    Thanks for the answers on voltage, I imagined it was the same as a car but I wasn't sure. As for the VRO...Let's just say I'm no stranger to the furious debate that exists over whether or not to disable this infamous pump. After long and careful consideration(not to mention complete teardown, inspection, and rebuild of entire VRO system) I've decided to stick with it.
    My engine was previously owned by a power company and the engine was maintained religiously. I have a VRO2 with achohol resistant lines...much better than the VRO1. I replaced the oil line and in-tank oil filter as well.
    The bottom line is, I dont want the same fuel/oil ratio at idle and WOT. Given the option, I'll use the VRO. Wish me luck!
    Thanks -Lewis
     
  7. JohnnyRuuDe

    JohnnyRuuDe New Member

    Messages:
    14
    State:
    vermont
    Whenever there is a gathering of boaters, the conversation usually turns to engines, then gravitates to stories about problems. One of the bones OMC owners like to pick concerns the oiling system. A typical conversation that we've all heard at one time or another might go something like this:
    "Yeah, my boat smokes like hell at low speeds and fouls the plugs," bemoans one boater. "Must be that worthless VRO pump acting up."
    "Uh huh, my neighbor had a blown engine," quips another. "Took out two cylinders on his V-6. The mechanic told him the VRO went bad. He didn't get an alarm or anything."
    "Come to think of it," the third member of the group chimes in, "my brother-in-law's offshore rig with twin outboards must have a flaky VRO; one motor always uses more oil than the other."
    "My engine is hard starting at times," says a fourth angler, "the VRO pump must be getting weak and the warning horn blows constantly whenever I run at full throttle on my 150."
    The truth of these stories is that none of the symptoms described is the fault of the VRO, yet the poor VRO pump gets the blame. Each rig has a different problem that is blamed on the oil pump because of misunderstanding, ignorance, and misinformation. Even many "experienced" mechanics do not have the knowledge of how the system operates and are quick to blame something that is unfamiliar to them.
    For instance, the first boat owner's problem (1) is an air leak somewhere in the boat's fuel system causing "foamy" fuel instead of a solid column of liquid. This aerated gasoline has less volume and less resistance causing the fuel pump diaphragm to cycle faster. Each cycle pulses oil into the foamy mix, increasing the oil:fuel ratio to the carbs creating a smoky exhaust.
    The mechanic of the second guy's neighbor (2) did not understand that the VRO mixes the fuel and oil internally then delivers the mixture through the fuel lines to each of the carbs. Since each carb receives the same oil to gas ratio, the VRO cannot cause only two cylinders to fail. Since the VRO did not malfunction, there was no alarm to sound.
    On the other hand, the brother-in-law's motors (3) have two different year's pumps on them. The later model VRO's pump more oil at low speeds than the original ones did.
    The last guy (4) blames the VRO because he once had a car with a weak fuel pump and a replacement cured its hard starting problem. Actually, he only needs a refresher in the correct starting procedure. As for the constant sounding horn at high speed that stops when slowing down, that's a fuel restriction warning, not a VRO malfunction. A lack of oil flow is a pulsing on and off horn every second or so.
    A decal is available (OMC P/N 335707) for the dashboard that illustrates the different warning signals and what they mean. This would be for 1995 and earlier motors, since 1996 the SystemCheck gauge uses four LED warning lights that illuminate to indicate LOW OIL, NO OIL, OVERHEAT, or CHECK ENGINE.
    A LITTLE HISTORY
    OMC introduced the VRO on the V-4 and V-6 engines in 1984. The pump consisted of a combination oil pump and fuel pump actuated by crankcase pulses through an air motor. Gasoline reformulation in those early years contained alcohols and solvents that softened the internal rubber components and caused pump failures and damaged engines. Back then, no company had alarm systems for a pump failure or loss of oil flow. OMC took care of the blown powerheads and improved the pumps considerably.
    The VRO2® was introduced in 1986 and included a "NO OIL FLOW" alarm. Changes included an electronic circuit to compare the oil pulses with the engine's RPM, a better oil pump piston, alcohol resistant seals, and a brown fuel outlet for recognition. Unfortunately, the damage was done. Public perception fed by uneducated mechanics put the blame for almost every engine problem on the VRO. No matter what happened to a motor, someone would utter "...must be a bad VRO."
    VRO OPERATION 101
    Actually, the much-maligned pump is very simple and reliable. It consists of four basic sections:
    the air motor,
    a fuel pump,
    an oil pump, and
    a "NO OIL FLOW" alarm system.
     
  8. gofish98

    gofish98 New Member

    Messages:
    116
    State:
    Lafayette Indiana
    WOW!:crazy:
    somebody did their homework:smile2:
    thanks I learned something today,
     
  9. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    Lewis,,,I agree with you 100%
    the vro always gets the blame from the boater that DOES NOT understand the VRO system
     
  10. roadkill636

    roadkill636 New Member

    Messages:
    551
    State:
    warrenton misso
    the homework is reading the owners manual and doing the REQUIRED maintnance
     
  11. Bubbakat

    Bubbakat New Member

    Messages:
    4,532
    State:
    McMinnvill
    I can tell you guys one thing that is a fact. Even a new one can go down without a seconds notice if not maintained properly. With that being said you guys do what makes you happy but me any VRO made before mid 1989 will come off my motors because they were plagued with problems


    roadkill636 as big as you are typing here is considered on the internet shouting. No offence intended here.