RC10GT carb and running...

[exitrooster]

First off, for the complete history of my RC10GT experience (it isn't much) but here's the previous thread I had going: http://www.rc10talk.com/viewtopic.php?f=36&t=20500 which was mainly about the fuel tank. Got it, got a new air filter kit, so that thread is pretty much done. Didn't post there because I didn't want to cause any confusion. Suppose I should just create a 'exitroosters official thread' rofl.. Anyway...

Here's what's new since the tank came in and was installed.. Try as I might I couldn't get it started. I went out and bought a
'c' cell glow plug warmer suspecting the one that came with it was faulty. Same thing. Long story short, come to find out it was bad, not enough pressure on the contact inside which runs down the line. A buddy who used to do gas powered and runs all electric now advised putting a dime in there, which worked. Car fired up. It ran good for a couple minutes. Had to adjust the idle as I was originally only able to keep it running by applying a slight amount of pressure on the gas/throttle. Eventually though, whether it was sitting with me, or doing a little test driving (what a blast!) the engine would like peg or "skyrocket" as I called it at the time, and I would then kill it cuz it sounded like it was gonna burn up. I have tried tweaking the idle as well as the high (the one with the brass sleeve around it listed as high fuel mixture rich/lean in the pdf manual I found), and when trying to readjust the idle screw was when I made my discovery/potential problem. It just doesn't seem right to me.

The carb has this shaft in it, that (originally) rotated back and forth allowing more air in. Ya'll know this. The problem is that now, when I squeeze the throttle on the rc radio, it goes in the brake direction, but will not pull the throttle/carb at all now. Looking at it (I know, text is the worst possible way to describe this, and my being new to the hobby doesn't help!) there is a rubber boot at the end, with the servo linkage and a nut (and a washer). The rubber boot appears to be the only thing holding that shaft in. Meaning, I can pull it out, and if I remove the boot I can literally get it out about 1/4 to 1/2 way, with only the servo linkage blocking it's exit. I remove that nut and washer, and pulled it out completely. Nothing seems broken or damaged or missing. I slid it back in, and it seems there is a spring or similar mechanism inside.

Is this normal operation? Is it supposed to be 'free' like that? And if so, any ideas why when I apply throttle/gas on the radio, it's not allowing it to adjust anymore? Is there something wrong maybe with the adjustment screw, actually, that's something I didn't check that I will when I go back out.. Maybe that adjustment screw is supposed to hold it in place, there was skinny notched out area that I was wondering about on the shaft - might be where the screw goes.. Thing is, the whole reason I started looking/inspecting this (which DID work before), was I was trying to get it adjusted, and the set screw was no longer 'opening' the carb as it had earlier today.

Regardless of whether I solved my 'why isn't the adjustment screw adjusting the carb anymore' issue, still wondering why it would start running 'out of control' assuming the carb as I described it, is operating as it should, and why it might not be moving with the throttle as it should/did.

FWIW, both my buddy as well as the shop I hit today for glow plugs both said this thing looks pretty new. Previous owner must'a been over his head or read too many places about why nitro is evil, lol.. Buddy already trying to convince me to just sell it and go electric, but I'm not prepared to give up yet

Thanks for your time and assistance,

e_R

[exitrooster]

Update: Must be right - went out and played with it to get that screw to get in that slot - works like a charm.. Man though.. the 7719 doesn't hold much run time, that or I'm burning through the fuel too fast.. I didn't time it, was to estatic with this being the first real run for me with it (read, having too much fun!), but I chewed through two tanks of gas in what seemed no more than 10-15 minutes. Again, for all I know it could have been 20-25, it's not official, just seemed like the time really flew when the fuel was aflow.

Any good tips/tutorials on tweaking the tuning, or anything else I need to know/be on the watch for? Things a blast - no wonder why so many people do 'real' rc (non new-bright/tyco/big box brand) driving..

[Midwest_Mudder]

My gt with the stock tank runs about 12 minutes from full. Thats continous running, not just putting around but gettin it going and throwing rooster tails out behind it.

As for the throttle problems. Are you referencing the plastic arm that connects to the servo linkage? The big nut holds it on, if that nut gets loose the arm can get out of wack and make it so it doesnt turn the cannister inside the carb. I was having the same problems when i first got mine, i tried 3 different stock carbs and until i pulled one apart and figured out exaclty how it worked i had not a clue as to why it wouldnt go. After finding that out i set it so that when the servo arm is inline with the vehicle (think servo arm straight front and back) i had it slightly pushing on the spring. give it a small gap between the set screw and the part that attaches to the servo arm, this will give you a nice amount of throw and make adjusting your brakes simple too. If you dont tighten that nut it can slip again, i also found that out the hard way. dont brute force it, but make sure that if that little arm is going to move its gonna have to have a dang good reason. This is all assuming you have the stock .15 AE motor with the stock rotary carb. if you have something different then it probably doesnt apply.

I also read your other thread, and im hoping you found an air filter. I dont run the stock oval shaped ones because i cant find filters for them, but i run a universal air filter and boot that i picked up from my local hobby shop. it was only 3 or 4 bucks and was near the fuel filters that i also picked up. My tanks were kind of nasty when i got the trucks and i really dont want any of the nasty stuff that was in the tank in my motor.

One more thing I learned the hard way, be careful where you run your wires from the battery pack in the rear. If they are anywhere near the flywheel they WILL at the most inoportune time get shredded and leave you to chase down your car, thank goodness for the throttle return spring.