throttle sticking

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Conspiracy of One
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I took out the savy today and about a minute in the truck killed. After that I noticed that the throttle was sticking badly. Also unless I give it some gas on start-up it doesn't start. I'm not real familiar with the inner workings of the carb so I don't know what could be making it stick. Any ideas?
 
savageXss1337 said:
I took out the savy today and about a minute in the truck killed. After that I noticed that the throttle was sticking badly. Also unless I give it some gas on start-up it doesn't start. I'm not real familiar with the inner workings of the carb so I don't know what could be making it stick. Any ideas?
Click to expand...

Your throttle may not be sticking. The small right angle piece of plastic (follow your linkage you'll find it) that swivels may be screwed too tight. Loosen it and then try.
 
Fxstrongside said:
Your throttle may not be sticking. The small right angle piece of plastic (follow your linkage you'll find it) that swivels may be screwed too tight. Loosen it and then try.
Click to expand...

I disconnected the throttle linkage and it is still sticking right around where the rubber boot meets the carb.
 
do you have a weird angel in which the carb linkage is connected to the throttle slide?? that might be a problem it should be straight... also try some after run oil squirt it on the throttle slide and see if that helps.. or post a small video if you can that would be sweet ... KEEP us posted !
 
wow sounds like the needle is bent but......you know where your linkage snaps on the little ball. can you wiggle that a little and move it in & out some times I feel a rough spot in the slide so maybe thats it.
if not pull the carb off (cover the inlet with like suran wrap) pull the air cleaner of and look inside at the needle.
also could check your return spring is it getting in the way of the sliding motion of the throttle valve..just some things to check
 
I just sprayed some oil under the rubber cover. It does not seem to have helped. IT seems to catch right when the throttle is in the farthest. I checked with and without the spring on and the result is the same. I'm worried, like Savagecre said, that the throttle/low needle may be bent. Can we get just a new carb, or is it time to upgrade engines? I have the K4.6 by the way.
 
Ok so I need your guys help! I have gas, its coming out the tail pipe. I have air, the filter is not dirty or clogged. I have spark, I just put a new glow plug in. And it will still not start. I even tried opening up the throttle while attempting to start it and I get nothing. Any ideas????
 
It sounds flooded. if you have fuel comeing out the pipe. to much fuel in the engine can damage it, cause it to not start( plug to wet with fuel).
Disconect the fuel, take the plug out, turn it over get fuel out. replace plug,try to start with the fuel line off still. If it starts then it was fooded.
 
hows the compression? engine should have lots of resisitence when you turn it over by hand. turn the fly wheel with your fingers. you shold feel the compression stroke. my 2 cents, no refunds
I have a 4.6 I'm rebuilding do to improper break in, I got it hot and cracked the piston, ouch!!!! live and learn.............
good luck
 
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i thought there was no danger of damaging your engine if it was flooded? and also my new motor was smoking a little during break in i haven't broken in a motor in a few years so i don't remember if it did it last time too?
 
if the throttle is sticking, remove the carb from the engine.

first take note of the position of the idle screw, then remove. this will allow the card slide to come free of the body.

check both the body and slide for signs of uneven wear (Photos if possible) and check the end of the idle screw. this can get damaged when the throttle servo EPA is not set correctly, the slide jams against the screw and causes burrs, which in turn cause the slide to stick.
 
You may not want to hear this, but this is a great time to get to know your carb, 1337.

Assuming your fuel is fresh, good glow at the plug, carb needdles are set to factory settings, fuel filter has un-restricted flow, ect.

I would do a carb re-build. Remove fuel lines and disconnect throttle linkage.
There's a securing bolt that's located inbetween the the carbs fluted inlet, and the cylinder casting. Remove the bolt and its two wedged carb lock inserts.

Now, gently slide out the carb from the engine. If you don't already have a blown-up illustration from your engine manual, get one on-line if possible.
I don't think it will hurt to start over with factory settings if your not exactly sure where the tuning was before this issue came to be.

But to be on the safe side, count the amount of turns it takes to seat the the neddles closed and then write down that info on a piece of paper.
now remove the nedddles and inspect for bends, warps, or breaks at the tips, ect.

Remove the silicon dust guard at the throttle housing and see for your self whats going on with this resistance you feel in the actuation of movement.
You might see something obviously wrong that you can deal with on your own. Check for sharp-edged or un-deburred areas on the moving parts.
If needed, go ahead and remove these ruff spots w/400 wet & dry sandpaper, along with any forien material you find.

O-rings have been known to break and in some cases, clog or obstruct free movement. keep all these parts clean and on a clean surface for safe keeping.

Do you know how to seal your engine?.... If we manage to get this issue taken care of, I would reccommend sealing the engine and carb for two reasons.

One, you should know of the importance and procedures of doing a propper seal on any nitro engine.
Two, It's a great time to do it when the engine is being inspected.

This is optional if you choose.

You'll need some RTV High-temp silicon gasket, (Copper Permatex reccommended) "Green Slime" silicon lubricant for the o-rings, and some teflon pipe fitting tape.

This sealing proceedure is something to keep in mind for all nitro engines.
Anyway, thats another thread.
Let us know what you found in the carb. At that point, will try to determine the next step in fixing the issue. cool?...

===================================================== Keep us posted, 1337 ============================================================
 
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gzus11 said:
if the throttle is sticking, remove the carb from the engine.

first take note of the position of the idle screw, then remove. this will allow the card slide to come free of the body.

check both the body and slide for signs of uneven wear (Photos if possible) and check the end of the idle screw. this can get damaged when the throttle servo EPA is not set correctly, the slide jams against the screw and causes burrs, which in turn cause the slide to stick.
Click to expand...
These are very good points to take note of. Good tips, gzus11
 
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I don't know if your engine is anything like the s25 (is it?) but I learnt the hard way that on at least the s25 you do not twist the carb while trying to remove it.
 
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