Recent content by OCboat

  1. O

    Carburetor's

    A lot of the repair kits cover multiple motors so sometimes there are gaskets and washers that aren't used for a particular motor. My the kit for my motor always includes a few things that I don't use.
  2. O

    1976 Mercury 500 only runs for a few seconds

    So I installed the new fuel pump diaphragms and gaskets and the new needle valves. It will now run without running out of fuel at fast idle but it still wanted to stall or run very rough at normal idle. During the time that I could get it to run at normal idle, I sprayed some seafoam in the...
  3. O

    1976 Mercury 500 only runs for a few seconds

    Definitely the fuel pumps. I put the gas tank above the engine and it ran by gravity feed for 10 minutes. I then put the tank back in the boat and it ran out of fuel in 1.5 minutes.
  4. O

    1976 Mercury 500 only runs for a few seconds

    Thanks for the detailed post. Yes the carbs are synchronized and the fast idle is working correctly. I can get it to start easily now and it will run at all throttle positions but only until the fuel bowls run out of fuel. If I pump the bulb periodically it appears that it would run all day...
  5. O

    1976 Mercury 500 only runs for a few seconds

    Yes. Small hole in gasket lines up with small hole in crankcase.
  6. O

    1976 Mercury 500 only runs for a few seconds

    I agree. I've got it running well as long as I pump the bulb when the bowl gets empty. I have another set of diaphragms on the way. The kit contains two "flapper ear" gaskets, one yellow nylon an one thinner rubber one. Do you know which one I should use or should I use both and in what order?
  7. O

    1976 Mercury 500 only runs for a few seconds

    Progress! I realized that I didn't change the short fuel hose from the engine side fuel bayonet to the tee as well as the two 2" hoses from the tee to the carb inputs. It will now stay running for longer than 2 seconds but it will not idle well or run for long with any neutral throttle advance...
  8. O

    1976 Mercury 500 only runs for a few seconds

    Serial number is 4357748. I have not removed the frost plugs since the kits that include them is a complete rebuild kit and are close to $100.00 each. Maybe I can buy them separately if I can find a part number for them. These are Tillotson ba3 carbs. I appreciate the help so far.
  9. O

    1976 Mercury 500 only runs for a few seconds

    Primer bulb is installed in the correct direction and it is moving fuel. It will fill the carbs until the needle valves close and will stay hard. I have not sprayed any premix but the engine will run for a couple of seconds on what little fuel gets into the crankcase when the choke is...
  10. O

    1976 Mercury 500 only runs for a few seconds

    There are two fuel pumps integrated into the sides of each carb. I just bypassed the male connector on the front of the motor in case that connector was causing the problem. The fuel is still going through the fuel pumps and the line is now connected back to the front of the motor since it...
  11. O

    1976 Mercury 500 only runs for a few seconds

    Any advice is appreciated. My previously running 1976 Merc 500 will not stay running more than a few seconds at a time. If I give it some choke as it's dying, I can keep it running for a little while longer but as soon as don't choke it, it will die. I took it out to the river a few days ago and...
  12. O

    1978 Mercury 1150 wiring schematics

    Hope this helps
  13. O

    Need not peeing on first season fire up

    I have a kit on the way. Thanks.
  14. O

    Need not peeing on first season fire up

    Did you figure out your issue? I have the same motor and mine does not pump well on muffs either. It will not pee at idle but if I rev it a little and then back down to idle it will start to pump a little. I haven't had it out on the water in 3 or 4 years and will be taking it out soon.
  15. O

    Spark Plug Picure - Diagnosis Please

    1976 Merc 500 - SN 4577xxx. This motor came with a 1959 Glasspar G-3 that I plan to restore some day but I thought I would get the motor running and put it on my 14' runabout. It has been sitting for a couple of years so here are the things that have been done to date. It was only getting spark...
See more
Top