Results 1 to 13 of 13
  1. #1
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6

    Help resurrecting my 10+ year-old T-Maxx's 2.5 engine

    Good evening all--hope everyone is doing well during these trying times.

    To keep this post short: I'm trying to get my T-Maxx 2.5 running again. The backstory is that my dad gifted it to me back around 2003... We ran it together for years, always taking care to clean and lube all components after each use... around 2007 we stopped using it and it sat in the garage until 2015 when I brought it back out again for fun--the flywheel was badly stuck, but we got it loose, flushed the engine and carb with plenty of WD-40 and it was running fine... then it sat in the garage for a few years more.

    The other week I used some of my newfound/forced pandemic time to try and get it running again. Applied plenty of WD-40 to the engine and carb, applied some new white lithium grease to servo gears, charged up the EZ-starter battery which I purchased new in 2015... but the engine won't start this time. The piston turns over without a glow plug in it, but when the glow plug is inserted it won't start.

    I thought it might be old fuel stuck in the brittle fuel lines (fuel not making it to engine), or the glow plug. So I purchased new fuel lines and a filter, new glow plug, new glow plug lead (the old one was badly worn) and fresh air filter oil. The fuel I'm using was just opened this week, although I technically bought the bottle back in 2015... my dad and I figured it was still fresh enough for use since it was sealed all this time, but maybe we are wrong?

    After all that cleaning and replacing and priming fuel into the carb, then clearing the engine in case maybe it was flooded, it still won't start up. Without a glow plug, it's turning and blowing out the WD-40 I've sprayed in, no problem. But as soon as I tighten up the glow plug up, it seizes. I recorded the video below to share here (shown starting with a fully charged EZ-starter battery, new glow plug, new fuel lines and new (old stock) fuel):

    https://drive.google.com/file/d/1Aed...ew?usp=sharing

    Any help or guidance will be very much appreciated! Thank you in advance.

    -Dan

  2. #2
    Marshal Double G's Avatar
    Join Date
    May 2008
    Posts
    13,970
    The engine sounds like it has good compression but it is either a weak battery and/or starter motor. Replace them or just go with a glow ignitor and pull start and it should start up.
    The Super Derecho

  3. #3
    RC Racer
    Join Date
    Mar 2020
    Location
    Southern Illinois
    Posts
    114
    Yeah, I get this a lot when I forget to charge my EZ Start battery. Get a fresh battery and it should do fine, (I'm assuming the EZ start motor worked fine last time you used it)
    I'm not afraid of my fellow man.

  4. #4
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6
    I really appreciate your replies, guys. So you're recommending I replace both the EZ starter batter (handheld) as well as the EZ-start motor itself?

    I last replaced the EZ starter battery around 2015. I didn't use it much, but it technically has been sitting uncharged for years. The EZ start motor on the truck is original and could potentially be the culprit, but I'm not sure if there's any way to test that independently from the starter battery.

  5. #5
    RC Champion grizzly03's Avatar
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    1,483
    I don't know if this applies to your battery, but when I switched out the NiCad battery in my EZ start to a NiMh battery it made a huge difference.

  6. #6
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6
    Quote Originally Posted by grizzly03 View Post
    I don't know if this applies to your battery, but when I switched out the NiCad battery in my EZ start to a NiMh battery it made a huge difference.
    I actually already use a NiMh battery in my EZ starter. Not sure if it originally came with one, but I upgraded to it back around 2015.

    Now that I am researching the EZ start system (handheld starter and motor) I am beginning to prefer just changing over to a pull start system. It looks like it would be less expensive and bypass the potential electrical system problems I could be facing. Hmm...

  7. #7
    RC Champion grizzly03's Avatar
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    1,483
    Do you have another electric RC you could test the battery in? That would help you determine what shape the battery is in.

  8. #8
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6
    Quote Originally Posted by grizzly03 View Post
    Do you have another electric RC you could test the battery in? That would help you determine what shape the battery is in.
    Unfortunately I do not. I just have the one T-Maxx. From what I gather based on what everyone is saying so far, it sounds like I should either replace the EZ-start system and see if that works, or switch to a pull-start system and see if that works.

    Could there be another reason why my engine wouldn't start? Maybe some part inside that needs lubricating after all these years of sitting? Just trying to figure out what sort of basic at-home maintenance I can at least try before buying parts.

  9. #9
    RC Champion grizzly03's Avatar
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    1,483
    After sitting in storage any residual fuel in the motor likely gummed up the bearings. So they aren't helping. The best thing to do would be to take the engine apart and check the bearings.

    Since you said it turns over without the glow plug you could try a trick that has worked for me in the past. Slightly un-tighten the glow plug and try starting. Sometimes this would lower the compression and aid in the engine turning over and still start. Once started then you would tighten the glow plug.

  10. #10
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6
    Quote Originally Posted by grizzly03 View Post
    After sitting in storage any residual fuel in the motor likely gummed up the bearings. So they aren't helping. The best thing to do would be to take the engine apart and check the bearings.

    Since you said it turns over without the glow plug you could try a trick that has worked for me in the past. Slightly un-tighten the glow plug and try starting. Sometimes this would lower the compression and aid in the engine turning over and still start. Once started then you would tighten the glow plug.
    That's a great idea about slightly loosening the glow plug, grizzly. Thanks for that tip, I will definitely give it a try.

    And I think I agree that it's time to take the engine apart and inspect for bad bearings and the like. Do you have any tips about how to clean and lubricate internal engine components? I use engine and carb cleaner on my motorcycle, but am not sure if that'd be too strong for the little Traxxas engine. Maybe just WD-40?

  11. #11
    RC Champion grizzly03's Avatar
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    1,483
    You can use soap and water,denatured alcohol or Wd-40 on the engine parts. I just wouldn't use water on the bearings,LoL.

    Maybe this will help you take it apart if needed: https://traxxas.com/support/TRX-Engi...Instructions-0

  12. #12
    RC poster
    Join Date
    Jun 2020
    Location
    NY, NY
    Posts
    6
    Hope everyone is having a good weekend--here's my Saturday update:

    After reading earlier comments, I used my peak charger to charge my 7.2v 1800mah EZ starter battery at 2amps. Was reading out at a steady 8.4v after charging. Good so far...

    I also charged a separate glow ignitor overnight, which I used to test the NOS glow plug I had in my T-Maxx. The plug glows a bright orange and looked good to me. Good so far...

    Also unplugged my new fuel lines and blew into them to make sure there were no obstructions in either direction. When blowing into the engine with the high speed needle removed and into the muffler, air moved freely in both directions. Good so far...

    Using advice from grizzly, I loosened my glow plug in the engine and tried to start it up, and the motor started running! But it was only while I had the EZ-starter plugged in and EZ motor turning. Once I let go, the engine cut out. So I reset my high speed needle to 4 turns out and my low speed needle to about 1.75 turns out, and also checked the throttle trim which looked good. Tried starting it up a few more times, and every time the engine would run and smoke was coming out of the exhaust, but it would cut out immediately as I let go of the EZ-starter button.

    I tried tightening and loosening the glow plug some and every time, no matter my needle or throttle trim settings, the engine would cut out. I think I'm moving in the right direction because I believe this has proven that my glow plug, EZ-start motor, EZ-starter battery and fuel lines are all functioning. Only problem is I'm not sure where to go from here...

    Some light brown-ish liquid was oozing out from the glow plug hole during my attempts to start where the plug was slightly loose. Is the next step to take the carb and engine apart for bathing in denatured alchohol and WD-40? Any thoughts will be appreciated... thank you in advance!

  13. #13
    RC Champion grizzly03's Avatar
    Join Date
    Dec 2014
    Location
    Adirondacks
    Posts
    1,483
    Sounds like you have a lot of old fuel residue. I would at least take the back plate of the engine and try rinsing (spraying) with WD40 to remove what you can. You can try that without any other disassembly of the engine. Drain the excess WD40 and put the cover back on and try again. If nothing else, you will be able to see what it looks like inside.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •