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Carb boot

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Bkyd Basher

Bkyd Basher

RCTalk Addict
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Location
Stamford Ny
RC Driving Style
  1. Bashing
  2. Racing
Hey guys i have one on order but what would it do if the carb boot was ripped? It will not rev out, but carb is openening all the way, sound logical? I would think it would be a serious air leak and rev high but it idles just fine. Kinda new to the savage but all the motors are the same, anything i could be missing?
 
Sounds logical because of the air leak from boot. New one should solve it. May want to check the seal as well. Make sure it's not cracked or broken.
 
I thought it was more than just a cover cause I've had mine off and inspecting it seems like it seals the slide as well. I'm not saying your wrong, just asking if your sure that I am?
 
Just a dust cover, but it should be replaced to keep the slide valve clean of debris and causing wear to the carb body and valve.
 
so any ideas where i should look from there? I sealed the engine and everything seemed ok inside. It is an OS .30vg. Whats a good place to start for tuning?
 
Stock setting for the OS .30 VG
HSN, 2 ¾ turns out from closed
LSN, Flush with ball link body and then 1 ½ turns in
Idle gap, ½ mm

That engine is real easy to tune if everything is in good working condition.
 
Last edited:
ok getting close, just starting hard and wont idle. What exactly do u meen with the low speed needle? Sorry I'm in the garage and working on it as we speak.... The minute i let out of the throttle(doing circles in the garage because the rain) it stalls instantly.
 
The lsn is located in the end of the carb slide valve. Slotted screw in the center of the valve that slides in and out of the carb.
 
ya sorry, i meant to say what do u meen about how u described the setting of the lsn. Flush with the outside rim of the arm and in 11/2 turns? If so i tried that and didnt help the idle at all. I've been all the way in with the idle screw and didnt really seam to do much?
 
You don't want to turn the idle screw all the way in. Never. With the filter element off looking into the carb you only want a gap of .5mm to 1mm max. The LSN should be flush with the rim of the carb slide then 1 1/2 turns in(clockwise).
 
If you have too big a idle gap then your gonna dump too much fuel into the engine for one and the Lsn will not be able to take over and control the flow as it should. It probly won't even start with a huge idle gap anyways and if it does it's gonna be a very high idle and take off with you. I'm not an expert by no means but I did become pretty good at tuning my engines by sound and performance and not based on temp readings. Once you find and seal any and all air leaks it's best to start your tuning at factory settings which should be rich for break ins. Then you leave the idle gap no bigger than 1mm. You can actually tune it and have good idle at .5mm. Refer to the tuning chart in nitro RC chat for a good guideline.

---------- Post added at 10:41 PM ---------- Previous post was at 10:40 PM ----------

https://www.rcnitrotalk.com/forum/showthread.php?t=60832
 
oh got ya. Ya i started at factory settings and idle where it should be. I kept goin up on the idle a little at a time but did not seem to make any difference. It is opening as i turn it but not doin much as far as running. It will not rev, carb is opening all the way so the servo setting is ok. It doesn't really run bad at low speeds but just stumbles big time at full throttle. Sounds like i am holdin the throttle at about 1/3. I did notice it seems like its not delivering fuel quite right, after it shuts off instantly the fuel in the line runs right back to the tank and emptys the line. Not sure if any of that info helps but thats what i am noticeing.Any ideas now?
 
Make sure your fuel lines are not cut or melted from touching the engine and pipe. Also did you seal the engine? Backplate, carb , and check cooling head seal and make sure your head bolts are evenly tightened. Other that an air leak it just sounds like it may be running too lean if it is cutting out at full throttle. If your seeing a bunch of blue smoke it could be too rich. Both my engines the trx and the dynamite will bog at full throttle when they are too rich.

---------- Post added at 5:27 PM ---------- Previous post was at 5:22 PM ----------

It may not idle if way too rich as well due to too much fuel being dumped into it at idle. You may want to pm one of the guys on here that have the OS engine experience. They may be able to walk you through tuning it better than I can. I only have experience with TRX and the .19T dynamite so far.
 
ok so yes engine is sealed. And it is hard to explain but it doesn't even bog, it just runs like u were holding it at half throttle or less. Runs smooth and even just wont rev up, but as i said carb is opening fully. I will check lines and cooling head and gaskets. Maybe signs of the motor being tired?
 
not sure. truck was given to me and had sat for a while. I took the engine all apart and found nothing wrong. All the bearings were nice and smooth and everything else seemed good also. Seemed pretty tite towards the top of the sleeve also.
 
Bkyd Basher said:
not sure. truck was given to me and had sat for a while. I took the engine all apart and found nothing wrong. All the bearings were nice and smooth and everything else seemed good also. Seemed pretty tite towards the top of the sleeve also.
Click to expand...

Does it still have good pinch?
 

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