Throttle issue

[Kris407]

sorry about the sound issue but i didnt know it until i watched the videos. the first video shows the problem with the idle and the stall when i gas it, the second video is actually part of the first one where the car is wanting to go but you can see i am not touching the gas and you can also see the brakes working and the car still idles. the third video is after i reset to factory settings and open the idle a touch, much better idling but still died when i hit the gas. i have leaned the LSN and its responding good so i will keep at it and update you with a video of it running. one more thing though, why is one wheel not turning unless i shake it around? i will post a vid of what i am talking about. thank you very much for your time.

this is the video of the wheel issue.

 

[Paul]

Ok so I had the same issue when I first started the tuning process. Needle settings did nothing to fix it. Finally realized it was my carb-gap and idle screw. I had set it to 1mm however the little clamp that the throttle linkage arm rides in for carb actuation, it was to tight and the linkage kept sticking ever so slightly but it was enough to cause my idle to be way high. Loosened the clamp so the link arm would slide freely, reset the idle set screw to make sure I was at no more than 1mm and this fixed my high idle issue. From there, the HSN and LSN were cake. It sounds like your having a similar issue. Could be that 1mm is to much of a gap for your kit. Could also be the throttle/break servo linkage doing something funky like mine was. I would close the carb-gap ~1/8 turn at a time until the engine won't idle, then back it out ~1/16 of a turn till it idles again. From here you should be set to tune. If you are absolutely sure the carb is good to go and I mean ABSOLUTELY sure, richen the HSN and lean the LSN ~1/16 turns, may take a little while but this should get you where you need to be.

Have you been flowing The Flow Chart? If you aren't it helps a lot.

Also in the last vid it looks like your front tires are spinning way faster than your back tires. Have you checked that the rear diff coupling is secure and not slipping on the diff shaft?

Something else I just noticed, make sure you're tuning with the air filter on.

 

[Kris407]

it was stalling when i would brake before i took the carb apart and cleaned it but now that has stopped. so tuning with the air filter makes a difference, does tuning with the wheels off the ground matter? OMG thanks for directing me to the flow chart it's a huge help!

this all began when i got dirt in the carb when i flipped it in the sand.

and something is definitely going on with the differential i just haven't figured it out yet. i haven't tried to address the issue but i will be learning as i go. i did remove them and take them apart to see how they worked when i had the engine apart for cleaning but i put them back together exactly how they came apart and the wheels were not having any issues or binding but when i cranked it up i noticed the wheels not turning equally.

 

[Paul]

Once you get it to stop creeping so much (should be able to make that stop all together) take it out and starting driving and tune while you do. If getting on the throttle bog's the engine and you are getting smoke your too rich on the HSN, no smoke to lean. Once the car is good on throttle then set your LSN. The way I've set my LSN is using the "pinch" method, with engine idling pinch the fuel line close to the HSN, engine should cut out in ~ 3 seconds, cold outside then you want it at about 5 seconds or so.

and something is definitely going on with the differential i just haven't figured it out yet. i haven't tried to address the issue but i will be learning as i go. i did remove them and take them apart to see how they worked when i had the engine apart for cleaning but i put them back together exactly how they came apart and the wheels were not having any issues or binding but when i cranked it up i noticed the wheels not turning equally.

Have you used blue locktite on the metal to metal screws when you put it back together? And I was referring to the rear most diff (in case there was confusion). The aluminum "cup" that fits onto the differential shaft may have come loose and so its not getting a good grip to spin the diff. If you unbolt the rear suspension gear from your chassis and if it slides free from the cup, then thats your issue right there. The diff shaft will have maybe a flat spot on it for the cup set screw (mine does). While I don't have the same kit I'm sure they're all very similar. Make sure that when you tighten this set scre down you've put a little blue locktite on it and that its gonna sit on this flat spot when you crank it down to tighten.

 

[Kris407]

i appreciate your time and advice bro, it's already made a difference and this problem is almost completely solved. i am feeling good about the progress we have made so far. i bought the buggy for $165 online and the guy really did not use it much and surprisingly it was in great shape. i replaced the steering servo with a stronger one and i tuned up and i ran it for a week and it ran like a beast! i pushed it to hard though and thats when all this fun started. the one way bearing is slipping like crazy now since i been yanking it a bunch lately, its pissing me off. lol i will be in touch after work tomorrow with an update on the buggy.

 

[Paul]

Bummer. Ok man. Keep us posted.

 

[Kris407]

going to check out the differential issue right now then i will start tuning again.

 

[ninnon]

the needles are responding to the slightest turn but it is doing a lot better!

Excellent choice of buggy- Fellow owner as well as a few other buggies and trucks. My issues with tuning issues for this were:
the fuel tank
the clutch spring
the servos
the fuel
check for air leaks

 

[Kris407]

Thanks ninno. its good to know another owner of the same kit, it is a great buggy and it takes a beating and keeps going. thank you for the suggestions on common issues you had, thats the info i want. i am finding that the biggest issue it has is the owner, lol.

 

[Kris407]

The rear differential is not broken and the teeth on the gears are good. The only thing I found were those two pieces of the small bearing you see in the vid. There is about 1mm of play on that bearing now but I don't know how it could cause the slipping.

And yes I did cut my finger trying to pull out the axl shaft

 

[Kris407]

okay so i am changing the grease to oil in all the diffs now. 10k in the front, 7k in the center and 3k in the rear. also i have to replace a couple bearings as well, the two pieces in the video are the bearing shields and dirt has gotten into them causing the problem. i think, i will be taking them apart again now and i will get the new bearings in the morning.

 

[ninnon]

okay so i am changing the grease to oil in all the diffs now. 10k in the front, 7k in the center and 3k in the rear. also i have to replace a couple bearings as well, the two pieces in the video are the bearing shields and dirt has gotten into them causing the problem. i think, i will be taking them apart again now and i will get the new bearings in the morning.

I had a lot of issues like yours and it turned out to be the clutch spring- one other thing you could try is checking for air leaks in thee fuel tank.

P.S I wish mine looked like that- no matter how much I clean mine it always looks a mess, I've got a chipped cooling head, bent exhaust, scratches everywhere!

 

[Kris407]

i am going to check the clutch after lunch when i get done with the center diff.

 

[Kris407]

thanks for the compliment i work hard to keep her looking new

 

[ninnon]

thanks for the compliment i work hard to keep her looking new

I'ts ok just as a reference my clutch spring broke 3 times because of me not bending the spring joint properly!

 

[Paul]

I'ts ok just as a reference my clutch spring broke 3 times because of me not bending the spring joint properly!

Those little clutch springs can be a real pain to install. Some manufactures claim their clutch kits make this much easier but I can't personally verify this. Maybe take a look at whats out there for when you need to rebuild your clutch again or just decide to replace it.

For instance, this Reds Racing.

 

[ninnon]

Those little clutch springs can be a real pain to install. Some manufactures claim their clutch kits make this much easier but I can't personally verify this. Maybe take a look at whats out there for when you need to rebuild your clutch again or just decide to replace it.

For instance, this Reds Racing.

I think my whole engine is on its way out, the cooling head is a mess, the exhaust is scratched and bent and doesn't seal properly. It was only the stock one though! Although that clutch looks pretty cool. After a bit longer I'll replace the exhaust and "repair" the cooling head and give it a good service.

 

[Kris407]

okay she has been totally rebuilt and i can promise that there is no dirt, ANYWHERE! All differentials have been cleaned and i put in new oil in them. every thing is looking good and i am heading out for some engine tuning.

 

[Kris407]

after one tank i was able to tune it to where it really ran great, engine temp hovering around 210-220 and no more idle problem at all. the wheels are all spinning in sync and the new differential setup feels good. new tires are on order now. i am happy with it and tomorrow i will be having fun in the dirt. thanks guys!

 

[Rolex]

i can promise that there is no dirt, ANYWHERE!

Okay, now try to KEEP it that way. Not only can I help with your tune-up, but I can recommend cleaning products and wax.