Buy Yamaha Outboard Parts

Announcement

Collapse
No announcement yet.

2008 F20 ESR won't start... troubleshooting

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 2008 F20 ESR won't start... troubleshooting

    Hello everyone! We recently purchased a 2008 Yamaha F20 ESR (short shaft electric start) for a small RIB/inflatable we are restoring. I did the usual tune-up (new plugs, oil change, lower unit gear oil change, impeller/water pump change, thermostat checkup and clean, fuel line/filter check/clean) and things looked dirtier than expected but passable. It wouldn't start though. So I figured most likely a fuel issue and cleaned the carb (it was the dirtiest carb I've ever seen). Still no luck unless I tried a little starting fluid, then it would start but only for a second. I then opened the fuel pump and it was stuck with caked on grit/sand. I cleaned it but that didn't help. I replaced the fuel pump with a new one and still no luck. I have now pulled the carb two more times and cleaned more and more and again and again. Still no luck, it cranks easy but never turns over and I know not to keep trying starting fluid.


    The main jet screw won't budget and the head is starting to strip so I wasn't able to pull that and clean it. But the pinhole is clear and free so I figured that might be ok?


    I read on the forums that the prime starter assembly can go bad and cause hard starts. I pulled that and noticed that the plastic housing is supposed to push a spring down and part of that housing is broken but it still looked like it would function holding the spring. Hard to know if that's working or not. I read that someone said they removed it and plugged that hole and it made the motor start... thinking maybe try that next? Part of me thinks that most likely the carb was just too dirty and it probably needs a new one but I'm trying to avoid spending that kind of $$... $400+ to still not be sure of the issue.


    One thing I've noticed is that in trying to start past kicker motors when I pull the start rope or the start button, one of those two lights will flicker on the motor for a second or two. I'm thinking that's the oil pressure light... but on this motor no lights flicker at all. Is that a sign of something else? Maybe a bad sensor or something? Maybe the kill switch is bad? But it did start with starting fluid which makes me still think fuel issue.


    I've pulled the spark plugs and they still look like new. Which again makes me think fuel is not getting through to create the spark.


    I purchased the manual and followed various steps but nothing strikes me as the simple solution. Any ideas or advice would be greatly appreciated.


    Thank you!

  • #2
    heated ultrasonic cleaner may help,

    but you have to think about where all of that nasty stuff was coming from.
    did you drain and clean the tank ?
    flush the lines, filter and pump?
    any stuff in those will head to the carb after you clean it

    Oh yea, starting fluid is bad on a 2 stroke because there is no oil for lube, four strokes have their own oil and lubrication system separate from fuel

    Comment


    • #3
      Thanks for the reply! FYI it is a 4 stroke outboard... so does that mean starting fluid is ok?

      And yes, before I tried starting it I used a new fuel source, tank, primer bulb and lines, and made sure all fuel lines to the fuel pump were not obstructed. New fuel pump after all of that too. The carb isn't visibly dirty after several cleanings... but as I said before I'm not able to remove the main jet...

      My real question here is if it is most likely the carb or could it be something to do with the ignition/plugs/compression?

      Thanks!

      Comment


      • #4
        Is the carb bowl fuel of fuel? I suspect not? Check the fuel line leading to the carb - could it be caked up with that same stuff you found in the fuel pump?
        2000 Yamaha OX66 250HP SX250TXRY 61AX103847T
        1982 Grady Weekender/Offshore (removed stern drive & modded to be an OB)

        Comment


        • #5
          Yeah so that's the weird thing... I unscrew the carb drain screw and it's never been full of fuel. But the fuel line TO the carb shoots fuel out when I press the primer bulb. So somewhere in the carb there is an obstruction... any ideas?

          Comment


          • #6
            I'm not overly experienced with carbs like some others, but from the few I've taken apart to clean... there's some awful small passages in there. Maybe it just wasn't cleaned well enough?
            2000 Yamaha OX66 250HP SX250TXRY 61AX103847T
            1982 Grady Weekender/Offshore (removed stern drive & modded to be an OB)

            Comment


            • #7
              Maybe a stuck carb float needle??...

              Comment


              • #8
                If you remove the carb bowl drain screw, and pump the primer bulb you should get fuel running out of the drain.

                if that does not happen you need to find out why the fuel is not getting into the carb.

                Comment


                • #9
                  That's good to know...thanks! I had a feeling the primer bulb should push fuel through the carb but wasn't sure. Ok, back for one more cleaning...

                  Comment


                  • #10
                    primer bulb when pumped should push fuel thru the fuel pump and filter into the carbs as long as the float opens the needle and seat to let it flow

                    Comment


                    • #11
                      Ok so I installed a new carb and it still didn't want to start... I sprayed a little starting fluid and boom it starts right up. The issue now is that you have to keep the throttle revving or it will die out. But it will keep restarting and revv's high and feels strong... The spark plugs look like they are firing (not fouled) and there aren't any signs of other issues that I can tell. I've been putting some seafoam through the system but nothing seems to help so far.

                      Again, clean fuel lines. New fuel pump and carb. Using new e-free fuel from a new small jug. Shot pressurized air through all water passageways (thermostat, etc). Tell-tale pushes water through nicely. New impeller/water pump.

                      Any ideas?

                      Thanks in advance!

                      Comment


                      • #12
                        well do you get fuel out of the drain when you pump the primer bulb now?
                        were did you get this other carb?
                        is it clean and adjusted to specs in the service manual?
                        does the motor have good compression?
                        it there good spark at all plugs?
                        is timing set to spec?
                        are the valves set to spec?
                        Last edited by 99yam40; 03-15-2021, 03:52 PM.

                        Comment


                        • #13
                          Good news! Got it running smoothly with a second new carburetor. The first one must have had an issue.

                          Anyway, we're back in action... next step is to get it mounted on our 11' RIB and get out in the ocean and do some fishin'. Thanks for all your suggestions and advice.

                          Comment

                          Working...
                          X