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+--- Thread: can't figure it out (/thread-7149.html)
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can't figure it out - AddictedtoNITRO - 06-04-2007
ok so I've tried fixing this problem numerous times to no avail. My buggy likes to stay at full throttle when you let off the gas. It ONLY does it when it's running. I think meatwad had a similar problem. so far I have changed the throttle servo, taken the ENTIRE buggy apart and cleaned and tightned with locktite every screw. No fuel line leaks. no air leaks in the engine. changed recievers and transmitters. changed battery packs.
I knoticed that if you remove the linkage off of the throttle the carb opens about 3/4 way. it slides very smooth. I have not yet put a throttle return spring on it because I never had a problem before and when I tried closing the throttle when it sticks open running it sticks! like the servo is saying nope not gonna happen. I'm thinking it has to be in the carb but idk. I disconnected the throttle arm and started the engine and it works fine so I figure it can't be 2 bad servo's lol.
It's beginning to really frustrate me
hope you can help
thanks
jeff
can't figure it out - Ponch - 06-04-2007
OK-first-throw a small rubber band or the little ring from a balloon around the ball end and the carb throat so it stays closed when you let go of it. (no servo attached right now)
Now make sure that when the truck is off and the linkage is attached to the carb that EVERYTHING moves freely. Wiggle/shake stuff around a bit just to see if anything could possibly catch.
Do you have another engine as a whole you could drop in there (running) so you could see if it's the carbeurator?
Ooohhh yeah I had something like this happen, just remembered- check that your servo lead is not touching the spur gear or it may have gotten chewed up and now when it sits(not running) there is nothing making the servo short out, but when it rolls it completes the connection and goes wot.
can't figure it out - AddictedtoNITRO - 06-04-2007
Ponch Wrote:OK-first-throw a small rubber band or the little ring from a balloon around the ball end and the carb throat so it stays closed when you let go of it. (no servo attached right now)the servo oneis ok I checked it all out plus put a new servo in it lol. Everything moves very freely as when I dissasempled and replaced everything I pretty mush made it new again if not better. I have another engine but I gotta take it outta the lsp urggh. I hate takin the engine outta this buggy. pita lol. I'll do the baloon thingy too now
Now make sure that when the truck is off and the linkage is attached to the carb that EVERYTHING moves freely. Wiggle/shake stuff around a bit just to see if anything could possibly catch.
Do you have another engine as a whole you could drop in there (running) so you could see if it's the carbeurator?
Ooohhh yeah I had something like this happen, just remembered- check that your servo lead is not touching the spur gear or it may have gotten chewed up and now when it sits(not running) there is nothing making the servo short out, but when it rolls it completes the connection and goes wot.
can't figure it out - kevinF - 06-04-2007
wait so when you let off the throttle to let it idle, it revs up?? or does the carb open up??
can't figure it out - Meatwad - 06-04-2007
i never had any problems.
can't figure it out - Ponch - 06-04-2007
kevinF Wrote:wait so when you let off the throttle to let it idle, it revs up?? or does the carb open up??
Yeah....any possibility that the low end is SUPER lean and the top is SUPER rich to compensate and when you let off it revs up?
can't figure it out - rocco79 - 06-04-2007
yes u did!!!!!! wit the hellturd
can't figure it out - Meatwad - 06-04-2007
hes talking about the mayhem. not the hellfire
can't figure it out - rocco79 - 06-04-2007
i was refering to a similar problem...
Get your pm's?
can't figure it out - Meatwad - 06-04-2007
yes thank you.
can't figure it out - AddictedtoNITRO - 06-04-2007
no it stays there. dosn't rev up. I can put around all day as long as I don't hit over 3/4 throttle
can't figure it out - AddictedtoNITRO - 06-04-2007
Meatwad Wrote:hes talking about the mayhem. not the hellfireactually the ofna
can't figure it out - kevinF - 06-04-2007
Ponch Wrote:Yeah....any possibility that the low end is SUPER lean and the top is SUPER rich to compensate and when you let off it revs up?
yeah what?? I asked 2 questions lol.
well if the carb is openeing up after he goes to idle then its NOT the carb settins, but if the carb closes completely then it could be a mixture of the high low and idle....so i would get the idle as low as you can first, then adjust the top and then the low
can't figure it out - AddictedtoNITRO - 06-04-2007
kevinF Wrote:wait so when you let off the throttle to let it idle, it revs up?? or does the carb open up??the carb opens up.
ponch I think the tune is actully fine. was runnin great before. I could run tank after tank and have a consistent temp and smoke
can't figure it out - Meatwad - 06-04-2007
what radio are you using?
can't figure it out - AddictedtoNITRO - 06-04-2007
futaba 3pm fm, tried a traxxas am radio and reciever AND a hot bodies tx/rx lol. I know a little overkill but I wanted to make sure It wasn't the radio. also 2 diffrent airtronics servos
can't figure it out - Meatwad - 06-04-2007
how much does your trigger finger move before the carb starts opening?
can't figure it out - J-Dub - 06-04-2007
You're nuts to run without a throttle return spring...
can't figure it out - AddictedtoNITRO - 06-05-2007
Meatwad Wrote:how much does your trigger finger move before the carb starts opening?it works like normal until after3/4 then it just stays there.
when I start it to test it I don't drive far lol I useually just blip f/t to see if it works. because when it goes it goes lol.
can't figure it out - Ponch - 06-05-2007
Pull open the carb manually, no servo attached, no return spring either. Open it full. Feel for any slight resistance at all. Now try to pull further.
I'm thinking that maybe your throttle end point is too high and it's pulling the slide too far and it's getting jammed there.
can't figure it out - chris arnold - 06-05-2007
i just wanna say, wow ponch what you have said is spot on, its most likely a hitch in your carb, it may need to be taken apart and cleaned or beburred, i wiould also slap an o ring or carb sping on for a return and see what it does.
can't figure it out - Traxxas_Junkee - 06-05-2007
Make sure your linkage isn't binding too.
can't figure it out - AddictedtoNITRO - 06-05-2007
Ponch Wrote:Pull open the carb manually, no servo attached, no return spring either. Open it full. Feel for any slight resistance at all. Now try to pull further.yea thats what I was leaning towards too maybe. weird though how it dosn't do it when it's not running
I'm thinking that maybe your throttle end point is too high and it's pulling the slide too far and it's getting jammed there.
can't figure it out - AddictedtoNITRO - 06-05-2007
I'll try it all out tomorrow didn't have time tonight. just got back from dropping nearly 30 grand on a (used) suv for the wife tonight
can't figure it out - Ponch - 06-05-2007
AddictedtoNITRO Wrote:I'll try it all out tomorrow didn't have time tonight. just got back from dropping nearly 30 grand on a (used) suv for the wife tonight
What did you get? We would have sold our suv to you for probably $15k...or less...it's an 01 Expedition, non eddie bauer, but it does have the 5.4L engine.
And WHY buy an SUV with the gas prices???