Recent content by jimmbo

  1. jimmbo

    Prop Help

    85+% of Boaters have No Clue about Rake and Cup, what they are or what they do.
  2. jimmbo

    Gas - Oil Mixture on old Evinrudes outboards

    Yes, I have watched People meticulously measure the Proper amount of oil, fill the tank, pour the Oil in, put the Cap on, start the Motor and go... Contrary to what the Oil Makers say about easy mixing, it isn't self mixing.
  3. jimmbo

    How to choose an old 2-stroke 150/175 Merc

    That was an interesting Read about the Development of the Merc V6. I remember reading how they made a V12, by placing 2 V6s kind of facing each other
  4. jimmbo

    Gas - Oil Mixture on old Evinrudes outboards

    If the Bearings are Well Lubed at the Specified Gas-Oil Ratio, more Oil doesn't make them Run Smoother. 16:1 was used prior to the Mid 50s. Some Engines, like the British Seagull, used a 12:1 or a 10:1, even in the 70s. They were Great for keep Mosquitos at bey Most engines from the 70s can...
  5. jimmbo

    Gas - Oil Mixture on old Evinrudes outboards

    OMC started using the Single Fuel Hose as Standard Equip on the High End Motors(some 35s and the V4s in 1958), though it had been offered in the Accessory Book for a few years, so the engines could be used on Boats with Large Fuel Tanks. From 1957, on, the Big Twins and V4s all had Antifriction...
  6. jimmbo

    How to choose an old 2-stroke 150/175 Merc

    The XR were Rated at the HP on the Decal. There is a 15% tolerance, but the main Difference between, an example, the Reg 150hp and an 150 XR2 is the Torque Curve of the Power Band. The XR2 had Beefier Midrange Torque, this was the result of different Exhaust Tuning and possibly slight changes to...
  7. jimmbo

    Replaced carbs in four stroke outboard - now hear popping

    On a 2 stroke, it was easy, as the Carbs had to be fully closed at Idle, and the Linkages between them could be set. Do you have the Factory Service Manual for that Engine? If not, get one
  8. jimmbo

    Prop Help

    Looking at the pic, it looks like a 15"(short) shaft motor
  9. jimmbo

    Prop Help

    What is the WOT Rpm range for your Motor? My Guess is 5000 - 5500. If so, you are over revving at 6000 - 6100 and will need about 3 inches more Pitch, so a 17 will be in the Ballpark
  10. jimmbo

    carburetor swap

    While it will bolt on, I wouldn't recommend it
  11. jimmbo

    Need better hole shot

    The Gear Ratio should be on the Drive, on the 3/4 Band on the upper gear houseing
  12. jimmbo

    Need better hole shot

    A loaded 21 ft, is not going to be a Ball of Fire, with any engine less than a Big Block. Torque is what you need, not more high Rpm HP. In fact, increasing the top end HP, of any given Displacement, often results in poorer Holeshot I have an 18.5 ft with a 5.7, it has decent but not...
  13. jimmbo

    Wont go past 2500 rpm

    Did you actually check to see if there is an Ignition Problem, or are just going to throw Parts at it? Higher Revs in Reverse, could be due to less load on the Engine, due to the Prop operating in the Exhaust Gases A Compression Test should be done How long have you owned this Boat? When did...
  14. jimmbo

    Replaced carbs in four stroke outboard - now hear popping

    Are all the Throttle Shafts in Sync, as in All are exactly at the Same Degree of Opening, or fully Closed at the same time? 2 Strokes were some much easier to work on.
  15. jimmbo

    1978 Johnson 85ML78C

    A Wire Wheel? That is a great way to ruin a Plug, it can leave metal from the Wheel imbedded on the Insulator. Sand Blasting is the best way to Clean Plugs, though the Electrode takes a Beating and will need to be filed to provide a Sharp Edge, and the Gap adjusted
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