Recent content by 75-JOHNSON

  1. 7

    40hp mercury tach

    I recently got a boat with a 1996 40hp mercury engine. It runs well, however the tach does not work. I made sure all the connections were tight on the back of the tach. I am wondering if it is possible to test if there is any power or signal coming through the wires that go into the tach? Where...
  2. 7

    Older Dowty Turbocraft Jet Boat

    I found one for sale locally and dont know to much about these old boats. It is a 1960 Dowty Turbocraft Boat with a ford inboard, through haul exhaust and berkeley jet pump. Im just curious, what are these boat made out of? i assume aluminum not fibreglass. Also are they suitable for fast...
  3. 7

    75hp johnson bog issue

    engine is a 1976 75 hp johnson, on a 15 foot trihaul boat. the carbs are clean, and prop is correct. The issue is, about 25% of the time when you go to take off it boggs out and dies. this is especially noticeable if you slowly increase the throttle. if you give it full throttle right off the...
  4. 7

    Inboard vs outboard performance

    I'm just wondering how inboards and outboards compare with power? Like would a 140hp out board perform the same as a 140 inboard? What are the pros and cons of each. if there is another thread like this feel free to let me know.
  5. 7

    My Boat "Spins Out" when turning hard

    Boat is a 16 foot tri haul, with a 1976 75hp johnson. i have the motor set so the anti cavitation plate is about half an inch higher than the keel of the boat. It has a brand new 3 blade prop. the trouble is is when i turn very sharp and give it full throttle, it accelerates hard then seems to...
  6. 7

    Winterizing 75hp johnson

    Yes i DID read the FAQ on this. So i will drain the lower unit but is there any other things on the engine to drain, or does all the water run out when stored upright? is it necessary to try and run some antifreeze through it or not really? basically just wondering if there will be any water...
  7. 7

    Whats an anti cavitation plate?

    probably a dumb question, but what is this? does my 1976 75 HP Johnson have one?
  8. 7

    Stereo On Older Boat

    Engine is a 1976 75hp johnson. Just wondering what the best way to run stereo power on my unit would be? obviously i do not want to just hook up to my one and only battery becasue then when i shut down the boat and listen to some tunes the battery will go dead. is it possible to run two...
  9. 7

    Older Electric Tilt/ Trim help

    Boat is a 15 foot fiberglass trihull, engine is a 1976 75hp johnson. It is equipped with electric tilt and trim. I admit i'm a newb, and dont know how to properly use these features. However, the tilt works good when no stress is on it. once in the water under load, it will hold itself, but if...
  10. 7

    75hp prop advice

    I am fairly confident that i have my 1976 75hp johnson running quite well. It is on a ~15 foot tri hull fibre glass boat. I pulled it on the scale today and got a wheight of 1700 lbs. (boat trailer was on scale still hooked to pickup that was not on scale) this is the combined mass of trailer...
  11. 7

    Thermostat Cover Lost?

    1976 75hp johnson had it out on the the lake for the first time in a long time and it kept getting very hot. i assumed something may have been the problem underneath the thermostat cover (maybe those little valves were stuck or something. anyways took it apart on the water and it all went...
  12. 7

    75hp johnson prop size/pitch?

    what is a good size and pitch to run on a 1976 75hp johnson? right now it has a 13.5 inch, 17 pitch and it has almost no bottom end, and takes forever to come out of the hole even with only one person in it.
  13. 7

    connecting rod on wrong way..big deal?

    just took apart my 1976 75hp johnson to change a broken ring and i noticed the connecting rod is on upsode down. the oil hole in it is facing down, not up. i beleive the motor has run like this for some time and the bearing on the wrist appears to be alright. i tried pushing out the wrist pin to...
  14. 7

    1976 75hp johnson top cylinder wont suck

    all three pistons have 120 psi compression. top cylinder wont suck very well. put some plastic wrap over carb ports and middle and bottom suck the plastic right in when you turn it over but top barely does anything. switched around reed valves and still no difference. any ideas?
  15. 7

    testing voltage off power pack 3 1976 75 johnson

    just wondering how to properly check the voltage coming off the power pack 3. i have a multimeter but when i hook it up the numbers on the screen just jump all over. supposed to be getting 130 volts. i dont know how to use a mutimeter very well so any help would be good.
See more
Top