backwards, not forwards

[the_rc_guy]

so while messing with my engine settings and such (just needle adjustments) i noticed that my wheels were spinning in the opposite direction (while buggy was on starter box) so i double check my assumption and place buggy on ground and ease up on throttle(if i go too much throttle too fast my engine dies) and it goes backwards. this is definitely bad. i also hear something rattling around somewhere around my engnie any clues as to what is wrong and how to fix? again, my buggy is going backwards, not forwards. what's the problem?



p.s. i know i'm using this forum as a troubleshooting forum. if this isn't 1 of the purposes of this forum just tell me.

 

[AC48]

p.s. i know i'm using this forum as a troubleshooting forum. if this isn't 1 of the purposes of this forum just tell me.

Thats exactly what this forum is for.

A nitro engine can run backwards without being damaged. Has it done this many times in a row? Check to make sure your starter box is turning the right way.

 

[greenwing7]

be sure that the starter box motor is turning the fly wheel over the correct direction

 

[the_rc_guy]

sweetness. so all of my problems don't seem to have a pattern! argh. (do you guys have problems? or is it just start and go for you guys?) anyways.


i start my car the same way (whether the final result is forwards or backwards) everytime and sometimes it goes forwards and sometimes it goes backwards. but when it does go forwards i can't seem to keep the engine running. from what i've read in other FAQs it seems that ONLY the LOW speed needle affects this. (am i right?)

so after i get passed starting my engine to keep it going forwards, and after finding the correct needle settings it seems that my throttle will not respond. my fail safe will kick in and pull it to brake, but my steering will still work. just my throttle is disabled. i replaced batteries but still about 30 seconds after taking it off the starter box it will be: throttle disabled, steering enabled. and it's always after i take it off the starter box never while it is still on it... any comments or solutions there?

 

[SkyMaxx]

So many questions...where to start...

Everyone has problems, that is why this forum works so well. We come here, share our problems, find and share solutions. That way, every now and again, we can luck out and just start her up and let her rip.

Your issue with keeping the engine running and the issue with the failsafe are related but separate issues. In order to troubleshoot the one you will need to take the other out of the loop.

I would first remove the failsafe from the problem in order to prevent it from providing more problems. Sometimes failsafes are not compatible with the radio system we plug them into and they create more problems than they help solve.

With the failsafe removed, I would return the engine to factory presets and get the engine running. From there, tune it (there are a number of ways to go about this and a lot of factors that will weigh in with regards to how you should tune the engine....but always start from factory presets for the engine in question). If you can get the engine running at presets, and can keep it running, that will give us more information to help us troubleshoot your set up. Try that...and come back to us with detailed information.

The failsafe should remain off the RC until we resolve the engine issue. Since the failsafe is there to prevent the RC from taking off, make certain your radio is on while this process of troubleshooting the engine is going on. Further, I'd recommend doing the troubleshooting with the RC off the ground....this should prevent it from running away. Place it on a brick or some other test stand that would let the wheels spin freely without making contact with something that may cause it to rocket off in any direction.

 

[the_rc_guy]

yes i did exactly that, but even with fail safe removed and factory settings(i think, i'm not sure. how do i know what they are?) i'm still having trouble keeping the engine going when i add a little throttle. here is a list of symptoms. oh and maybe these are signs of an improperly broken-in engine? can you keep an improperly broken-in engine running correctly? or does the break in just affect the lifespan and race-performance? anyways. symptom list:

1) after i get it started. i'll add a very teeny tiny bit of throttle and then when i release it, it will idle high with wheels spinning(but not full throttle)
2) if i adjust it too lean, rpms will shoot sky high when i apply the brake and then engine will idle higher than above
3) throughout the throttle range (when i can get it revved up) it sounds rough. and then it sounds the most rough right before it dies.

also i just let it sit on the starter box so the wheels are off ground.

so lastly. how easy is it to sell one of these things? and will i be losing lots of money? or do they pretty much have decent resale value? (like what u paid for it)

 

[SMaxxin]

What engine do you have, maybe someone can tell you what factory setting are.

Rc's are very easy to sell

You will loose your a$$ selling it, regardless what condition it's in!

 

[the_rc_guy]

What engine do you have, maybe someone can tell you what factory setting are.

Rc's are very easy to sell

You will loose your a$$ selling it, regardless what condition it's in!

ya i got a ofna ultra lx comp the rtr version. and it has a .26 force engine or something like that. i bought it for $220 as a display unit. and have put about another $100 in accessories. but back to above:

1) after i get it started. i'll add a very teeny tiny bit of throttle and then when i release it, it will idle high with wheels spinning(but not full throttle)
2) if i adjust it too lean, rpms will shoot sky high when i apply the brake and then engine will idle higher than above
3) throughout the throttle range (when i can get it revved up) it sounds rough. and then it sounds the most rough right before it dies.

 

[SkyMaxx]

When you apply thottle it gives a little bump and then nothing but idle. When you apply brakes, the rpms shoot sky high and then it idles...

Those two statements would cause me to think perhaps your throttle servo is reversed. Check (with the engine off) to make certain that the throttle servo is doing what it is supposed to. When you throttle up, the servo should pull the carb open. When you apply brakes, it should push the carb to its idle position.

As for the needle settings, will look into your RC and the stock engine and see what I can find.

 

[the_rc_guy]

your throttle servo is reversed.

lol! i know my throttle servo is definitely not reversed. it's obviously NOT an OBVIOUS issue here. there's something else wrong.

When you apply thottle it gives a little bump and then nothing but idle.

i didn't say that.


and i'm thinking it has to do with the fact that my engine was incorrectly broken in. i also think it has to do with that "rough" sound whenever i give it a little throttle

 

[SMaxxin]

lol! i know my throttle servo is definitely not reversed. it's obviously NOT an OBVIOUS issue here. there's something else wrong. i didn't say that.

All problems are obvious to someone with experience, your new to nitro so he is starting with the basics.

and i'm thinking it has to do with the fact that my engine was incorrectly broken in. i also think it has to do with that "rough" sound whenever i give it a little throttle

The problem your having is most likely a tuning issue. I have seen engines that had no brake in at all and still ran good. Your idle is affected by both needles but more so on the LSN. From what I can understand it will idle but won't go...Try leaning the HSN 1/8 turn at a time.

Almost forgot, make sure the glow plug is good.

 

[the_rc_guy]

All problems are obvious to someone with experience

yes i agree.

your new to nitro so he is starting with the basics.

yes i agree

Try leaning the HSN 1/8 turn at a time.

i've been doing this but it gets to the point where it just idles even higher.

i found the point where this happens with the LSN and since it was going bad if i leaned it or richened it from that point. i figured that would be the "equilibrium" point for the LSN. so i started on the HSN. for the HSN i started screwing it inwards (right-hand rule, which makes inwards clockwise) but it would just idle super high. so i figured that was bad.

...my ears hurt.

 

[SkyMaxx]

As SMaxxin has pointed out, I am going with your experience level. Sometimes the OBVIOUS is not so OBVIOUS and sometimes the OBVIOUS is the real problem. SO try really hard not to discount the OBVIOUS.

Have you taken the time to go to the manufacturer's website for your engine? Have you tried returning the engine to factory presets on the needleds? How did the engine run when you did this?

As for the rough running...it could be the glo-plug as mentioned, it could be the exhaust is loose, it could be that the cooling head is loose, it could be any number of things. All I am trying to do is get you to a ground zero that is familiar to everyone and troubleshoot from there.

Sounds like you have a decent dialogue going with SMaxxin, so I will let you try and resolve your issue with his help.

 

[SMaxxin]

Here is a link to the manual for your engine, follow the directions under "Needle Settings"

http://www.ofna.com/pdf/eng-force25-26.pdf

The Master needle is your HSN, Side carb needles is your LSN.

Remember when you close your needles don't over tighten them are you will pinch the o rings, stop as soon as soon as they get snug. Once you have returned the needles to factory settings try to run it and let us know how that works.

If you decide to start tuning start with the HSN (per manual). Once you get the HSN set you can start with the LSN is necessary (it's not always needed). Do you have a temp gun? If you do what temp is it running at?

I suggest installing a new glow plug be fore you try to start it.

A video of it running or trying to run would be great!

 

[greenwing7]

I believe his engine is a little lean on the low end and rich on the high needle it idles high and then dumps tons of fuel in since it is rich on the top end and thats what is causing it to die?? give it a try what do you have to lose right
good luck!
did you do the break in yourself on this engine??

 

[Plaidfish]

I'd suggest sealing the backplate and carb to eliminate air leaks as well......we all know new engines can have em.....

 

[the_rc_guy]

okay i will try very hard not to discount the obvious

Have you taken the time to go to the manufacturer's website for your engine? Have you tried returning the engine to factory presets on the needleds? How did the engine run when you did this?

i'm not really sure what they mean by turns. at first i assumed turns were full revolutions, but i found that i was runnign WAY to rich so then i started assuming turns were half revolutions. based upon that it was pretty much having the same problems.(for factory settings) also with the "barrel stop screw" (what the manual calls it.) i took off my airfilter(is that where i am to look?) to check out the "spacing" but as i was turning that barrel screw i couldn't really see what was moving? so i tried best to leave it where i found it.

did you do the break in yourself on this engine??

yes and i did it assuming half trigger pull on transmitter was half throttle, but i was wrong since half trigger pull on transmitter is actually full throttle

I'd suggest sealing the backplate...

the backplate is the part that houses that one-way bearing? for the pullstart? maybe it has something to do with the fact that i broke my pullstart. so i took out everything inside the pullstart and left the one way bearing on with just the housing of the pullstart put back on (with nothing inside) could that be a problem? i switched from pullstart to starter box.


also with this dang starter box i been wearing down that rubber piece that makes contact. there is so much black rubber powder all over the place. does that happen to you guys?

A video of it running or trying to run would be great!

i will see what i can do about that. cuz really all the guys at my lhs are cranky oldfarts that shun college kids like me in the hobby. also they are all about rc aircraft rather than rc's with 4 wheels.

so Smaxxin, i been reading through the directions for factory settings and it keeps referring to the master needle for "lean and rich" but when i read about general tuning in other places it says that i should be using the LSN for "lean and rich" adjustments? you say that master needle is my HSN?

maybe that is where i'm going wrong gah. something obvious no doubt...

 

[SMaxxin]

so Smaxxin, i been reading through the directions for factory settings and it keeps referring to the master needle for "lean and rich" but when i read about general tuning in other places it says that i should be using the LSN for "lean and rich" adjustments? you say that master needle is my HSN?

maybe that is where i'm going wrong gah. something obvious no doubt...

Both needles are used for "lean and rich" you have to find a balance between the two. I didn't say don't use the LSN I said once you return the needles to factory setting start with the HSN, then go on to the LSN if necessary. A turn is one full revolution. Check out the pic, I marked the needles

Circle = HSN
square = LSN sometimes this is on the opposite side (the part that slides)
line = idle screw