Not Moving?
 

Hello,

Few weeks ago i purchased a GST 7.7. I ran three tanks of gas through it and then started playing around with it in my parking lot. At first, i was having a hard time getting the truck to move. With the controller in hand i could hammer it down and the truck would rev up like it was going to move and it would move... just about three inches... and stop. So, i started leaning it out thinking that it might be getting too much fuel and it seemed to be helping. However, tonight i got out again and start playing with the truck and it is doing the same thing. I can hammer it and it will rev up and stop. What is causing this? I need help!! Where do i look/start??

Also, the breaks are somewhat stopping the truck now, but not what i would expect. I expect the truck to do a nose dive when i apply the breaks, this isn't happening. When applying the breaks, the truck will stop, but by no means is it immediate.

Thanks,
Magikman

RE: Not Moving?
 

hey Magikman, Welcome to the forum and welcome to CEN Genesis Series ownership. This is a common question, first I 'll ask if you checked ALL of your screws to be sure they were ALL tight?? Then check your set screws on the drive inputs into the front and rear differentials, They are most likely loose or not tightened up on the flat portion of the pinion shaft. Just take out the set screw, put just a dab of blue or red locktite on the screws threads, line up the hole on the flat and reinsert the set screw and tighten as tight as you can get it. Do this on both inputs and you should be good to go...

And as far as the brakes go. You need to adjust them and the radio to push better and harder on the brake cam lever. You could even do endos when the brakes are set properly so be careful not to adjust too much stopping into it.


BTW I would respectfully suggest you use the search feature to see if you question has been asked before. And if you ask and dont get a response, that usually means it has been asked before. Just a friendly suggestion.

Good luck and have fun!!!

RE: Not Moving?
 

I had search and read many threads looking for an answer to this issue and i did read about people having a similar issue. But i was thinking that perhaps mine was different. The reason i was thinking this this was different is because the engine RPMs fall when this happens. Meaning, i hammer the throttle, it starts to move and then the engine dies down to nothing. All this happens while the carb is fully open. Now, i was under the impression that if the linkages were broken/loose the motor would be turning unimpeded. i.e. no force stopping it. Is this wrong? I am double checking all the screws now.

Thanks for the suggestion. :)

RE: Not Moving?
 

Also, you did not mention anything about a break-in. What break-in procedure did you use?


So if I understand you. You can start the truck, idle it up to temprature(BTW what temp does it get up to and what temp did you break it in at?) drive it slowly around but when you quickly pull the throttle trigger it bogs down? right?

If thats true then you still need to lean out the HSN, until it no longer bogs when you hammer it, if that does not help then go the other way(richen it up)..You could Definitely benefit from a tuning dial to help.
You can find the best available @ [link=http://www.rchardware.com]http://www.rchardware.com[/link]. And they are on sale this month!!!! There are now 2 versions, Race and Sport. Very high quality and the price is very right. I have three 2 sports and and a race, it made my tuning SOOO much easier!! Try it out you'll like it!! I promise..

And dont forget to have fun!!

RE: Not Moving?
 

it sounds like your too lean on the needles if its dieing at full throttle, richen up the needles perferably the low speed needle. and for not moving it sounds like either the brakes are dragging or the either the front or rear drive shaft needs attending to. thats the problem with a center diff if a axle looses traction you will lose all drive. i would start it up and hit the throttle and it should tell you if its the brakes or the drive shafts.
http://www.rcuniverse.com/forum/m_38..._7/key_/tm.htm
its happened to me so i think it might be the culprit click on the link and see.

RE: Not Moving?
 

Thanks for your help. I just purchased a tuning needle from the site referenced. It seems as though that my problem is with the engine tuning because there is enough thread lock on most of the set screws, etc. to keep anyone from *ever* breaking it. In fact, there was enough on the steering assembly and bottom plate to strip the screws when trying to remove them. Have either of you replaced the allen head screws with a flat or even phillips head? It seems as though they would be much more durable.

Also, i hate to sound stupid, but what, exactly, is the LSN? I know that the HSN is the main tuning screw that comes out the top of the carb, but what the hell is the LSN?

RE: Not Moving?
 

Magicman, you wont be dissappointed with the N-Tune dial, And shipping will be quick..

HSN=High Speed Needle
LSN=Low Speed Needle

No I have not changed ANY screws to Flat blade or Phllips, I believe the hex's work VERY well. In fact, so much so I replaced all of the Phillips on my truck. Sometimes you have to use heat via pen torch or something that makes good heat, to melt the threadlock to loosen those stuborn screws.

Hope that helps

RE: Not Moving?
 

I know what they stand for, but what i don't know is what is the LSN? The only thing that it could be is the idle control. If this is indeed the idle control, why call it the LSN?

I am sorry for my seemingly stupid questions but i can't seem to find this information anywhere else.

RE: Not Moving?
 

the lsn is located on the carb. its the screw right on the carb that moves its copper or simmilar in color.

RE: Not Moving?
 

the hsn is the one that the fuel line goes to the idle screw is i believe black and on the side of the throttle body there is a brass screw thats the lsn. this should make more sence :D

RE: Not Moving?
 

While i have you two here, what batteries do you all use in your trucks/cars? What radios do you use? What else do you use? I purchased a pen torch and a tuning dial today. What else should i get?

RE: Not Moving?
 

the extra stuff i did to mine so far is add lithium grease on all metal gears even in the tranny, i use rechargable batt nimh 2600 i built my own packs and dont use the batt tray under the truck and strap it up front. i also relocated the on and off swich from under the truckto the inside of the radio box and added a rubber switch cover so it made it semi water proof, water will damage the switch and cause a runaway. the older trucks gen -nem didnt come with throttle return springs which is a plus for the gst owners we needed to make our own.i also on the genesis le added a xtm velocity boot to the for/rev lever, the kind that go over a cvj on the axles and rubber cemented it down so no dirt or water get into the tranny gears. i also used clear rubber silicone on all screws that go into plastic so they dont unthread themselves on a good day of bashing. nothing is going to garentee that something wont break but most of what i covered is by my mistakes and wont happen again for me so i am glad to pass it on to someone else. the only thing that i keep breaking at the moment is the right rear shock, if you land wrong on a 8 ft jump i just seem to blow only one shock every time. i guess you cant fix stupidity:D.

RE: Not Moving?
 

I went out last night to try and tune my truck and get it running like it is supposed to. After playing around with different settings for a while, i came to the conclusion that no matter what setting i set my truck on, none of them fixed the problem that i was having. So, i started looking at other options. After playing around for a min. i placed the truck up on my leg and hammered the throttle and as usual it started out and died. After this, i reached down, grabbed the servo linkage and started opening the throttle manually and what i noticed is that it didn't die out. So, i come home and look to see how far the carb is being opened when the throttle (from the radio) is "hammered" and it is open completely, perhaps even a little past the carb wall. So, this brings me to my questions:

1) How far should the carb be opening when it is at full throttle?
2) Can someone take a picture of their carb at full throttle and send me that picture or post it here?


Thanks...

RE: Not Moving?
 

this thread also helped me out a lot, as i am having these issues as well, i assumed it was mainly to poor tuning, but i havne't been out yet to mess with it and see. Thanks.

Also it seems like my driveshaft on the front of the veh (under) is rubbing against where the steering servo is mounted and i think where the battery box is, i fcouldn't really see where to adjust it so there was more of a gap there...any suggestions? i can post pictures if im being confusing.

RE: Not Moving?
 

sorry i dont have to much time to read all the post on thiss topic but i read what you wrote and you should have ideled it 2-3 tanks before even trying to drive it let alone lean it out;)

RE: Not Moving?
 

I am very well aware of the fact that i need to break in the motor before trying to tune it. The problem with my truck was that the carb was open ALL the way. i.e. it was open too far. All i wanted was someone to tell me HOW far it *should* be open not that i should break in the truck.

Thanks for your help...

RE: Not Moving?
 

Hey M4gik, Sorry about the delay in response time. I have been very busy. On full throttle, your carb should only be as open as the throat of the carb, in other words when you look down the carb and fully pull the trigger(the truck power switch should be on but the engine off) the slider should only clear the opening, no further. if it does go further then adjust your EPA on the transmitter so that it does not open any further. Be very sure when you let off of the trigger the carb slides fully closed. If you think pictures will help, I can post a couple for you..



Good Luck and Most of All Have Fun!!

RE: Not Moving?
 

im glad your aware of the fact witch means for the first 2-3 tanks you didnt try and give it ANY throttle now just do what TRD said and you will be just fine;)

RE: Not Moving?
 

Not *any* ?

CEN Manual:

RE: Not Moving?
 

m4gik,

You did fine, giving it some throttle to keep it alive is what you're supposed to do... You can even run the truck a bit right of the bat. That won't hurt it.
Altho... Always follow the instructions when in doubt, which is what you did it seems.

Robert,

Please try to be more accurate with your posts before you submit them, and you should always read the whole thread before replying to threads.
This is not an attack on you at all! Sometimes you sound a bit sarcastic which is not always the best way to go in a forum (hard to make out how people mean the sarcasm and someone might get upset)

Lastly take TRDs advice m4gik... he seems to really know his stuff! [sm=thumbs_up.gif]