• If this is your first visit to the iboats.com Boating Forums, be sure to check out the FAQ. To post a question or comment, begin by signing up. To start viewing messages, select the forum that you want to visit from the selection below.
  • ALL iboats Forum Members and Guests:
    To show our appreciation for your participation in the Forums, we're offering an exclusive Forums-only discount good for an additional 5% off your iboats.com order for a limited time.
    To redeem, simply call our Customer Service Team at 800-914-1123 (Open M-F, 9am - 8pm Eastern Time) and mention the Forums 5% off discount. Offer excludes engines, trolling motors, and electronics.


Announcement Module

Help Tip: If you have a question that has not been answered to your satisfaction in the archives, it is always best to start a new thread of your own. By starting your own thread, you will receive the maximum number of views by forum members.

Below are some additional forum policies in hopes of all iboats members will follow, Thank you.

1. Please do not reply to old threads or hijack existing threads. Old threads of a technical nature are like a library book, Please do not write in them.

2. Old threads should be considered archives and used for reference only. Please do not reply to them.

3. Do not take over someone elseís thread (aka hijack) with your own question, even if it is similar. If you have a question that has not been covered to your satisfaction in the archives, it is always best to start a new thread of your own.

4. If you have a question for the original poster (OP) and the thread is over 30 days old, send the OP a PM, he may not even visit the forums any longer, or may not notice your question in the old thread.

5. By starting your own thread, you will receive the maximum number of views by forum helpers that may not even notice your question when itís posted at the end of someone elseís thread. And those answers will be specific to your particular issue.

6. Please do not post to threads that have been inactive for more than 3 months unless you are the original poster. We have very active forums and any thread that remains inactive for that long should be considered "dead". It is especially confusing when there is an entirely new question posted to an old thread.

7. Posting at the end of any thread is considered to be hijacking the original posters thread which in turn subjects the thread to be closed if it continues to happen thus not making it fair to the original poster in the future had for some reason he/she needed to return for additional information or provide an update of the problem solved which is always welcomed within a reasonable amount of time frame.

8. Please note that you should see a red banner pop up near the bottom of each inactive thread asking you not to reply to old threads. The Red banner will read: Please note this thread has been inactive for 90 days. For the best results, please start a new thread.

Thank you all in advance for doing your part in helping iboats run a smooth ship.

Additional forum rules linked below.
See more
See less

1973 20 HP Johnson Outboard

Page Title Module
Move Remove Collapse
Conversation Detail Module
  • Filter
  • Time
  • Show
Clear All
new posts

  • 1973 20 HP Johnson Outboard

    Hey Guys, Hopefully someone can help me with this. I just bought a boat and motor and it had sat up for 2 years. I found trash in the fuel pump and carburetor and cleaned it thoroughly. I also replaced the spark plugs and gapped them to .030. I replaced the fuel lines within the coweling. Now it cranks right up and runs for about 15 minutes and then becomes sluggish and starts to die out. It eventually quits and oh yea, I have to leave the choke open about halfway for it to run.... I am new to this so any advice would help..

  • #2
    Re: 1973 20 HP Johnson Outboard

    Does the spark look good on both plugs? Does it still look good after you've warmed up the engine and it dies? My guess would be a bad coil(s) that shows up when it warms up. Maybe you need choke because you're only running on one cylinder? Have you checked the compression?Is it pumping water OK? Maybe it's overheating.Those are my thoughts anyway...Brent


    • #3
      Re: 1973 20 HP Johnson Outboard

      Could be overheating, John. If you haven't changed the water pump impeller, do so now. They are only good for a couple of years, including time that they are in storage.If you need choke to keep it running after warm up you might have missed some gumming in the carb orifices.Let us know what you find.