fbpx

 

Experts,

My plane, a Sling 4, with a 914 sat for 9 weeks (weather in New England), and when I went to start it this past Wednesday (burped the engine and checked the oil - AOK), I got a few blades, but not a start.  Tried a few more times and it gave less and less each time.  The final time it didn't even move.  Seems to me like a classic weak battery, but is there anything else to consider?

The battery is an EarthX ETX900 (https://earthxbatteries.com/shop/etx900) and I had charged it about 3 weeks ago (I use a LiPo smart charger).  Since then the temps had dipped into the 20's F range and the plane is hangared.

I have a VPX electronic circuit breaker system and it was reporting 13.1 V on the battery (If I recall correctly).  Isn't that enough to turn the starter?

I'm really hoping it's nothing more than a weak battery.  The charger has been connected since Wednesday, so I'll try again tomorrow.  But, if that doesn't work, what else should I consider?

BTW, do I need to burp the engine again if it never started?

Thanks!

  • Re: 914 Won't Start After 9 Weeks Not Run

    by » one year ago


    Hi Craig, 

    1) Once you have ruled out the battery as the problem and confirmed it's not turning over fast enough at any point then it's then a case of working downsteam. Solenoid then starter (bushes, oil seals, sprague clutch) It would probably be better and less stressful to call in the big guns at that point and get one of us full timers to take over. 

    2) With regards to burping, it's relaxing and covid friendly so why not.. costs nothing   


    Thank you said by: Craig E Maiman

  • Re: 914 Won't Start After 9 Weeks Not Run

    by » one year ago


    Firstly the burping is only really to return the oil to the tank so that you can check the level. It can also be useful just to make sure that the crank is rotating freely and that everything feels 'normal'.

    With regard to your battery, assuming that it was charged correctly only 3 weeks ago and that nothing was connected to it that would have drained it then it is either faulty or you have a problem in the starting circuit. Assuming that the starter is fully functional then I would check the electrical connections including the ground connections. You could use a multimeter to measure the voltage getting to the starter when cranking the engine. If you compare this to the voltage across the battery whilst cranking you will see how much you are losing. There will be some loss through the cables, the connections and the starter solenoid but I would imagine that it shouldn't be more than about 0.5V.

     


    Thank you said by: Craig E Maiman

  • Re: 914 Won't Start After 9 Weeks Not Run

    by » one year ago


    It definitely turns freely and has had no issue starting in the past.  I should also note that this engine has very few hours on it.  About 60.

    I do have a spare battery I can try if the charge doesn't do the trick (hope so!).  After that, I'll check connections, though I don't know why it would turn a bunch of blades the first time then fewer and fewer if it were a connection issue.

    If I can't figure it out relatively quickly then I'm definitely calling someone to get this fixed as soon as possible.  So, if it gets to that, I'd love any recommendations.  I'm at 6B6 in Stow, MA.


  • Re: 914 Won't Start After 9 Weeks Not Run

    by » one year ago


    This is fairly common on the 914 and 912's that sit and more common if people are using auto fuel vs 100LL. After they sit for long periods the idle jet can become clogged. Loosen the clamp on the rubber carb socket and push the carb back out of the socket. It may be stiff, but wiggle it and apply a little pressure. It will come out. This will allow just enough play to lift the carb 1" - 2" and turn it outward and take the bowl off. The idle jet is right next to the main jet in a hole on the air intake side. Use a straight tip screwdriver to unscrew it. Then get about 6" of 16 ga. - 18 ga. wire and strip back about 4" of it. Unwind ONE single strand and then poke it down through the center of the idle jet. Once all the way through slide it back and forth and rotate it. This will not damage the jet. DO NOT use a drill bit or any thing else or it may enlarge the hole. Once cleaned out follow that with some carb cleaner spray and then some high pressure air. It should be clean now. Replace the idle jet. Make sure when you screw the carb bowl back on you use a torque wrench because if you over torque the screw you may wapr the bowl and you'd have to buy a new one. Make sure you FULLY seat the carb back in the rubber socket and tighten the clamp.

    This should help. I see it fairly often and the above procedure works every time. I've been doing it like that for almost 20 years.

    p.s.

    Make sure the battery is back to full charge. If you have a low idle rpm setting then try cracking the throttle a tad. Higher idle rpm settings don't usually need this.

    p.s.s.

    IF you have to old style black starter think hard about going to the newer gold colored starter. It will make a difference.

    I just ran out of p's and s's. LOL


    Roger Lee
    LSRM-A & Rotax Instructor & Rotax IRC
    Tucson, AZ Ryan Airfield (KRYN)
    520-349-7056 Cell


    Thank you said by: Craig E Maiman

  • Re: 914 Won't Start After 9 Weeks Not Run

    by » one year ago


    This may sound crazy but I heard a while back that when it gets cold enough and the engine won't start to slightly warm up the modules with a heat gun and I friend with a 914 experienced the same problem it worked for him, it started after 3 blades, it happened again the next day with the cold engine. so he replaced both modules to fix the problem 

    you do have to have a fully charged battery so it turns the engine for a few blades .

    try that it doesn't cost any thing just heat them slightly 


    Thank you said by: Craig E Maiman

You do not have permissions to reply to this topic.