Results 1 to 23 of 23
  1. #1
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51

    Tuning woes. Fuel perhaps?

    Greetings,

    Tuning (or even starting) my .15 Pro is a pain. I have checked everything and sealed everything. I'm going to try a couple more things before I chuck it. I've tried stock settings and that's not even close to get 'er going.

    One thing I want to try is different fuel. The old Dynamite Blue Thunder (20%)may be too old. I don't know if it goes bad or not but I am going to get a different fuel when the hobby store opens (half an hour). ANY recommendations?

  2. #2
    RC Turnbuckle Jr. Wolfslash16's Avatar
    Join Date
    Mar 2012
    Location
    Riverton Utah
    Posts
    4,339
    If you want new fuel, I'd get O'Donnel 20%. It works great for me! I could use some more info on what your engine sounds like, or what it does when it starts... Good luck!
    Sl2sh Slayer Summit Sl4sh Teton/Rally T-Maxx Pnde

  3. #3
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    I will take my engine completely apart, clean it and put it back together. It usually runs right away but with 2 or more full turns out of the high speed needle. I think, as a result, I am getting too much oil and eventually, it'll stall and wont start until I clean it or de-flood it and spend 3 or 4 min trying to start it.

    I get about 5-10 min run before I need to break down the engine and put it back again. It's 1 hour in the shop for 10 min (if I am lucky) of fun. I have a different post describing what happens and even a video or two. This thread is mostly about fuel. Can fuel go bad? Can it cause what is happening to me?


    Here is a link to the other thread: http://traxxas.com/forums/showthread...91#post5291891. Feel free to post in either.

  4. #4
    RC Turnbuckle Jr. Wolfslash16's Avatar
    Join Date
    Mar 2012
    Location
    Riverton Utah
    Posts
    4,339
    Can fuel go bad? Can it cause what is happening to me?
    Yep. Fuel can go bad over time. The nitro will evaporate, leaving just a lot oil, just like the problem your having. Try changing fuels. Good luck!
    Sl2sh Slayer Summit Sl4sh Teton/Rally T-Maxx Pnde

  5. #5
    RC Qualifier
    Join Date
    Sep 2011
    Location
    New York State: Snowbelt
    Posts
    747
    If it doesn't work, you could send me the engine
    SUMMIT |MERV * FIVE-T * REVO-E| T- MAXX-E

  6. #6
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    I'll likely just keep it around the play with

    VIDEO WITH NEW FUEL & GLOW PLUG

  7. #7
    RC Qualifier
    Join Date
    Sep 2011
    Location
    New York State: Snowbelt
    Posts
    747
    I was joking. I just bought a new 3.3, wouldn't need that 1
    SUMMIT |MERV * FIVE-T * REVO-E| T- MAXX-E

  8. #8
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    Again, the stock settings mean nothing but a starting point.... if yours needs to be at 3 turns to start put it at 3. Again, watch your temps and tune the darn thing. Every engine is different, and if it is within operating temps, go with it.
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  9. #9
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    Well, I took the whole engine apart, and the carb and cleaned it all out. Very unfortunate, I broke the head off of the LSN. It's set but no more tuning until I get a new carb.

    I am actually 4.25 turns out on the HSN. What are appropriate temps for these engines?

  10. #10
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    Depends on outside temp if checking head temp..... i have an exhaust temp senser from an old boat i had to keep mine in the safe range, and have had mine anywhere from 250-350* on head temp range. Head temps are "altered" by ambient temps. If you keep yours around 250-300* range u "should" be ok, but not my fault if it blows. Lol
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  11. #11
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    Easier to go by sound, and smoke signs than head temps once you know what to look and listen for.
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  12. #12
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  13. #13
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    After 5 min of running and 5 fast passes, the head temp was 270. I won't hold anything against anyone but that seems ok, yes?

  14. #14
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    Yes, as long as smoke was good..... now tune in the lsn.
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  15. #15
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    Can't. Broken head.

  16. #16
    RC Competitor
    Join Date
    Aug 2012
    Location
    Unique Racing Engines
    Posts
    74
    Sent you a pm.
    3 t maxx 3.3, 2 revo 3.3, 2 slayer pros, what next

  17. #17
    RC Turnbuckle Jr. Wildman4910's Avatar
    Join Date
    Jun 2009
    Location
    Cocoa Florida
    Posts
    3,921
    I noticed in your vid the clutch bell was turning the spur gear as you ran the ez start, you need to check the clutch for a broken or bent clutch spring.

    If it is broken or bent it will make tuning a nightmare.
    Look out for the tree/crunch!

    LiPo? Naw NITRO!!

  18. #18
    RC Qualifier
    Join Date
    Dec 2011
    Location
    Woodward, OK
    Posts
    424
    I also noticed in the video that it looked like your fuel bottle did not have the cap on it. If that was the case, it will not take very long for your new bottle of fuel to be bad. The alcohol in the fuel will evorate very fast which will change your nitro,oil, and alcohol contents. That is just my .2 cents worth.
    T-maxx 3.3
    Rusty 2.5r
    Summit VXL
    Nitro 4-tec

  19. #19
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    The clutch bell will freely spin and will spin for 10 minutes without the engine mounted and not contacting the spur gear (and if I actually spin it. something has to make it go). I assume that is normal. I took everything off the engine that did not require any special tools, including the spring. Everything seems 100%. When I mount my engine, I mount it so everything will freely spin. IE: The clutch bell will spin when I am starting but it'll all be centrifugal forces. I can easily hold it in place and it wont spin while starting. Also, the engine is mounted so the clutch bell is not jammed right up against the spur gear but is close enough that they catch together.

    I have seen no instructions on motor mounting. Any info you guys could tell me would be great.

    Also, I have a cap for my fuel.It's not connected tot he bottle and it was left of in haste to make the vid. Thanks for the heads up but I am very conscious about the fuel and moisture issue.

  20. #20
    RC Turnbuckle Jr. Wildman4910's Avatar
    Join Date
    Jun 2009
    Location
    Cocoa Florida
    Posts
    3,921
    The reason I pointed it out is if will spin with just the ez starter how much is it going to spin when the engine idles?
    Look out for the tree/crunch!

    LiPo? Naw NITRO!!

  21. #21
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    I have seen nothing on aligning the engine. How is it suppose to be seated?
    T-MAXX CLASSIC, .15 Pro, EZ-START, 27.145MHz.

  22. #22
    RC Racer
    Join Date
    Aug 2012
    Posts
    191
    Use a piece of paper, like photo copier paper, & place that between the gears when you push them together to align them, it should be able to pull though the gears without ripping but should still need a little bit of pressure to pull out, the gears will turn as it pulls though. Make sure the gears are aligned straight & not at an angle to each other.
    I read that somewhere, may have even been on this site, or another, can't remember. I have never done it this way though, I don't have a problem aligning them by eye & feel.
    REVO 21tm grunt & JQ Products "The Car" GO NITRO

  23. #23
    RC Competitor
    Join Date
    Sep 2012
    Posts
    51
    LOL! It took a week but I really appreciate this.

    I essentially thought that once the gears grip each other without slipping but not pressed against each other so hard that it's more likely to break on the first flex was good enough. Turns out, right in the middle (tested with a piece of paper).

    When I get my new connecting rod, I'll give 'er a go.

    I can dig it! Thanks!
    T-MAXX CLASSIC, .15 Pro, EZ-START, 27.145MHz.

Posting Permissions

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