Results 1 to 10 of 10
  1. #1
    RC Enthusiast
    Join Date
    Feb 2015
    Posts
    39

    Rebuild, replace, or power up 2.5?

    I'm trying to bring a Jato back to life. I have a Jato 2.5 that looks to be in bad condition. The piston top is dark and the carb is sticking. The motor has never run under my ownership. I'm waiting on parts to try and start it. I'm still new to the RC hobby, but I've watched tons of videos and would feel comfortable rebuilding a motor. I'm just not sure if that is the route I should go. I think the simple thing to do is to power up to the 3.3 but is it too much motor? I know, there is no such think as too much power. I've just read of some people having a hard time keeping it on the ground after upgrading to a 3.3. I would appreciate any feedback.

    One other thing? How do you guys get to the nut that holds on the carb? I wanted to remove the carb to clean it up while I figure out what to do.

    Last thing, is the power up program worth it? It seems like you can buy a 3.3 from amazon for the same price and still keep your engine. I may not be looking at the right engine though.

    Thanks for any help.

  2. #2
    RC Enthusiast
    Join Date
    Feb 2015
    Posts
    39
    I think I figured out how to remove the carb. I'm not sure what the motor casing is but I can probably figure it out tomorrow. Jumpinjoe628 posted this on another link.

    "Remove air filter, unplug the wires going to the EzStart, unscrew the three screws that hold the Motor casing to the engine and remove. Use the multi-tool (6mm I think) that comes with your car and remove the nut at the base of the carb. Give the threaded end a couple little taps till you see the other end pop out and carefully wiggle the carb up and out."

  3. #3
    RC Racer
    Join Date
    Jan 2014
    Location
    Philadelphia
    Posts
    119
    I would just get a new 2.5r or 3.3 motor. If the motor u have now is in bad shape just start fresh since u said u are new to the hobby. With a new motor u can perfect ur tuning skills which is a major part of nitro rc. Starting with a rebuilt motor which u stating isn't in best shape will prolly have tuning issues. The old motor u have now u can take it apart experiment on it etc. I ran a 2.5 in my jato and got tired of getting left behind by my cousin 3.3 jato so I went to a 3.3 and now an os .21tm. The 3.3 is a huge upgrade in speed from a 2.5 but u learn how to control it with practice. As far as keeping wheels on the ground my 2,5 motor used to wheelie my jato, just set ur suspension soft and low to help take them a bit.
    Am I the only Philly basher?

  4. #4
    RC Enthusiast
    Join Date
    Feb 2015
    Posts
    39
    Thanks for the information PhillyBasher. I'm a different kind of philly basher than what I think your name stands for, haha. Go Cowboys! Just messing with you, I really appreciate the help. I think you are right. The new 3.3 is probably the way to go. I'm still trying to figure out if the power up program is any better than just purchasing a new 3.3 online. Maybe I'm missing something.

  5. #5
    RC Racer
    Join Date
    Jan 2014
    Location
    Philadelphia
    Posts
    119
    Lol, yea eagles are looking kinda crazy right now lol....but yea the 3.3 is gonna take sometime getting used to the power and speed. When it's tuned correctly it is a great motor! Buy a 3.3 on eBay for the same price as the power up plan and keep the old one to rebuild. Then buy a used revo and put the 3.3 in it and the 2.5 back in the jato...lol...before u know it u'll have 6 Rc's!
    Am I the only Philly basher?

  6. #6
    RC Champion
    Join Date
    Sep 2010
    Location
    Chicago, IL
    Posts
    2,226
    Honestly, I love getting old motors running. If it still pops when you turn it with a glow plug in (has compression), then it will run again!!

    Rebuilding (new piston and cylender) is stupid. Its like $55 and for $65 you can get a brand new 2.5R from powerup, so Id not do that.

    To unstick everything, take the engine as much apart as you can.
    Option A: Soak everything in nitro fuel. Get a cheap gallon of fuel (doesnt even have to be car fuel), and a 3lb cottage cheese container/big coffee can, and soak everything for at least 24 hours.

    If its really gummed up, go to Goodwill/similar, get a old crock-pot and a gallon of automotove 50/50 antifreeze, and boil the engine in antifreeze for 12-24 hours. Only do this with the metal parts of the engine, not the carb tho. That will clean out everything and shine it up.

    For $65 tho, a new 2.5 is a great option, tons of power for a little truck like the jato. Just do the breakin right.
    This parrot is NO MORE!!! This is an ex-parrot!!!

  7. #7
    RC Enthusiast
    Join Date
    Feb 2015
    Posts
    39
    haha, I could see how you could quickly accumulate RCs. I bought my t-maxx (first ever real RC) about 3 weeks ago. Then bought this Jato a week or so later. That's kind of what I was wondering, buy a 3.3 online and keep the old motor to rebuild. I'll probably go that route.

    On the other hand, I finally got my EZ-Start wand in the mail yesterday so I was able to turn the motor over for the first time. I don't have the correct tool to remove the carb yet so I just tried spraying it down with carb cleaner then used a little mystery oil to try and get the slide moving again. It's still not right, but I added some fuel and actually go it to start pretty quickly. Like you said PTTM, that was fun to get that little motor running. I couldn't get it to idle correctly because the carb is still gummed up but I'm going to the shop today to pick up a couple of tools I need. Then I'll remove the carb and clean it right. I'm really not sure what kind of shape the motor is in due to my RC inexperience. When I turn the flywheel with my thumb, it doesn't seem to have anywhere near the compression that my OS .18cv-r has on my T-Maxx. I guess I'll see how it runs when I get my RX and tires in the mail this week. Thanks for all the tips on cleaning the engine!

    Separate question. I replaced all 6 of my turnbuckles last night since the others were rusty and one was bent. I didn't know where to place the two little spacer/washers that came with the turnbuckles. If anyone has a picture or can explain that would be great.

    Yes PhillyBasher, the eagles are doing some crazy things right now. Who knows it could work out though.

  8. #8
    RC Racer
    Join Date
    Jan 2014
    Location
    Philadelphia
    Posts
    119
    The spacers go on the front turnbuckles in the center of vehicle to angle the turnbuckles.
    Last edited by Phillybasher215; 03-10-2015 at 12:35 PM.
    Am I the only Philly basher?

  9. #9
    RC Enthusiast
    Join Date
    Feb 2015
    Posts
    39
    Ohhh, I see now. I just found the exploded views page on traxxas and spotted it. Thanks for the help!

  10. #10
    RC Champion
    Join Date
    Sep 2010
    Location
    Chicago, IL
    Posts
    2,226
    Ya, those are fun. 2.5 doesnt have much compression at all, but it does go up when the engine warms up and the piston expands.
    This parrot is NO MORE!!! This is an ex-parrot!!!

Posting Permissions

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