• 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.
  • **** The forums will be undergoing maintenance tonight approximately 9:30pm-midnight MDT. Thank you for your patience during this time. ****

Announcement

Announcement Module
Collapse

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.
http://forums.iboats.com/forum-rules-guidelines-405/
See more
See less

1975 70hp evinrude wont fire after carb rebuild

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


  • 1975 70hp evinrude wont fire after carb rebuild

    I have been playing around with this engine for a while now
    when i first got it i tried to start it well the floats where messed up so i decided to rebuild the carbs

    1.it did run for a few seconds before the rebuild it back fired out the exhaust
    then flooded
    2.I then checked for spark good on all cylinders
    3. checked compression good and even on all cylinders about 125psi
    4. rebuilt carbs
    5.replaced fuel pump just in case
    6.tried to start
    7.seems like no gas is getting to plugs they are bone dry
    8.now gas is starting to spit out the front of the carbs

    all most like the is no crankcase vacum

    any help with this would be great

    thanks Bob


  • #2
    Re: 1975 evinrude wont fire after carb rebuild

    you could have a intake leak and check the timing is their fuel coming from the carb jets?


    what type of carb? make and modal
    Last edited by Fisher freak; June 29th, 2010, 08:56 PM. Reason: more tips
    If there isnt a manual....redneck it.

    Comment



    • #3
      Re: 1975 evinrude wont fire after carb rebuild

      What are we working on?

      Comment



      • #4
        Re: 1975 evinrude wont fire after carb rebuild

        carb
        If there isnt a manual....redneck it.

        Comment



        • #5
          Re: 1975 evinrude wont fire after carb rebuild

          1975 Evinrude what? Gas flooding out the front of your carbs sounds like floats hung open.Are you sure theyre opening and closing/seating properly?Did you do link and sync after the rebuild?
          sigpic
          DONT FORGET TO PUT THE PLUG IN!!HAPPY MOTORING
          BOATS:HOLES IN THE WATER,ALL YOUR MONEY GOES IN.GOTTA LOVE EM

          Comment



          • #6
            Re: 1975 evinrude wont fire after carb rebuild

            sorry forgot the hp 70
            model number 70573 e

            Comment



            • #7
              Re: 1975 70hp evinrude wont fire after carb rebuild

              i checked the float level 3 times and made sure they where not binding before putting it back together

              all linkage hooked up exactly how it came apart

              will have to check to see if the jets are sqruiting

              Comment



              • #8
                Re: 1975 70hp evinrude wont fire after carb rebuild

                bump

                Comment



                • #9
                  Re: 1975 70hp evinrude wont fire after carb rebuild

                  Bob,
                  I have this engine as well. Carefully check routing of the fuel line from pump to middle carb. It can get pinched between silencer and the engine if not careful. When you look you'll see an opening in the silencer for the hose. I made my fuel line a little extra long so it's not kinked at the carb and allows enough length to route through the opening in the silencer body. This is an awesome engine when running correctly, Good Luck...
                  Jon

                  Comment



                  • #10
                    Re: 1975 70hp evinrude wont fire after carb rebuild

                    After putting the bowls back on the carbs,did you blow into the fuel intake with the carb right side up[and you could blow through it]and then turn the carb upside down and blow into it[you shouldnt be able to blow through it as the float/ needle valve should be closed],,,, if you can blow through it while upside down,your float is catching on something,gasket,inside of bowl,pivot pin might have a catch on it,,or the needle valve has trash in it,or needle valve could be mis aligning with the seat.,,,,so there are quite a few things that can cause float problems,,,,also one overlooked simple thing,,,make sure the spring that holds your needle valve to your float is holding the needle valve snuggly to the bottom of the float to insure it is moving right and tight with it.
                    sigpic
                    DONT FORGET TO PUT THE PLUG IN!!HAPPY MOTORING
                    BOATS:HOLES IN THE WATER,ALL YOUR MONEY GOES IN.GOTTA LOVE EM

                    Comment



                    • #11
                      Re: 1975 70hp evinrude wont fire after carb rebuild

                      update:
                      got it to fire up today just wont stay running
                      i think i will look into the floats again
                      and i think i may have a coil pack that may not be 100%

                      thankyou everyone for your help

                      i will keep anding updates on progress

                      Bob

                      Comment



                      • #12
                        Re: 1975 70hp evinrude wont fire after carb rebuild

                        update

                        well she does run now but cant keep her running
                        it seems like it breaks up when you rev it

                        the spark seems alittle weak

                        think i may try a power pack next

                        sound like a good idea


                        thanks Bob

                        Comment

                        Working...
                        X