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good idle?
- Thread starter tsiap
- Start date
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RC Addict
RCTalk VIP
No, they shouldn't, provided you have everything set up. If they are, with no throttle input from you, you can adjust your trim tab until they don't. One thing--it is not a good idea to break in your R/C with the wheels suspended off the ground. That is sooo old-school. To do so while stabbing the throttle can blow your engine. If you need a proper break-in guide PM me and I will send you the info. Good luck!
If your idle is correct, the wheels will not turn. Sometimes during the first couple of tanks of break-in, it's hard to get the idle low enough with out stalling.
MrClean
Hardcore RCTalk User
If you are breaking it in, I wouldn't worry about it too much as long as the motor isn't racing like crazy. I think these engines 'act up' a little bit while breaking them in.
Like Racer said, you can try adjusting the idle down so it's not revving as high.
Like Racer said, you can try adjusting the idle down so it's not revving as high.
brad55102
RCTalk Addict
Dont forget, it might not be an idle problem. Make sure you check your clutch shoes and spring. This will give you a huge headache. If you mess with the throttle and LSN and nothing fixes it then check your clutch shoes and spring. (replace)..... only $4
- Thread starter
- #8
update
today i went for the break in for the first time
the first start was a mess! very difficult to start.... it took me about a dozen time of starting before the idle was stable....and between each starting the piston was jam at the TDC....
so when the revo was rolling and i was doing the procedure of the first tank ..... 2sec count to 1/4 throttle ...the engine stall...couple of time like that...but the truck was so sluggish all the way to reached 1/4 throttle ...
after that the second tank: 2 sec count to half way throttle.... the idle start to be a little high.... so i'm leaving it like that....couple of run and the engine cut's....restart...etc...
the idle was too high that my revo start to moving by itself from a dead stop...so i'ved turn the idle screw counter clock...but the idle was to high again...
so i continued my run but each time that i'm giving some gas and i release...the rpm drop down for few second and reved up pretty fast
and the sound of the motor was not stable....it was too much fluctuation between high and low rpm...
i shut up the engine...and that's it...for today
it tooked me like almost 1 hour and a half for doing 2 tank....
feel free for any comments
today i went for the break in for the first time
the first start was a mess! very difficult to start.... it took me about a dozen time of starting before the idle was stable....and between each starting the piston was jam at the TDC....
so when the revo was rolling and i was doing the procedure of the first tank ..... 2sec count to 1/4 throttle ...the engine stall...couple of time like that...but the truck was so sluggish all the way to reached 1/4 throttle ...
after that the second tank: 2 sec count to half way throttle.... the idle start to be a little high.... so i'm leaving it like that....couple of run and the engine cut's....restart...etc...
the idle was too high that my revo start to moving by itself from a dead stop...so i'ved turn the idle screw counter clock...but the idle was to high again...
so i continued my run but each time that i'm giving some gas and i release...the rpm drop down for few second and reved up pretty fast
and the sound of the motor was not stable....it was too much fluctuation between high and low rpm...
i shut up the engine...and that's it...for today
it tooked me like almost 1 hour and a half for doing 2 tank....
feel free for any comments
Captain Chaos
RCTalk Addict
I am not the expert but it sounds like it may be a little lean on the bottom for break in.Lets see if one of the vetrans has some advise.
RevoAxial28RR
RCTalk Rookie
thats pretty tipical for the 3.3 from my experience, like mentioned, it does sound like you need to check your controler trim, richen that low speed, lean the high speed just a tick 1/8 turn max, break ins suck the fun out of a new car, but ya gotta do it
RC Addict
RCTalk VIP
I would start by looking for an air leak in the fuel system. Check fuel lines for tears or holes. Check the carb for leaks as well. That is the most common cause of erratic idle. Keep the HSN on the rich side--it never hurts to keep her rich but you will kill your engine running it too lean.
Once you find where you are sucking air from you can work on getting the idle set.
Good luck and post back if this doesn't help.
Once you find where you are sucking air from you can work on getting the idle set.
Good luck and post back if this doesn't help.
MrClean
Hardcore RCTalk User
My Revo3.3 did the exact same thing, they run like crap during break in. They are set so rich from the factory (mine was anyway) that the low end is horrible. So trying to hit 1/4 throttle over a 2 second span is almost impossible. I just fought my way through the first few tanks. I could never figure out why the idle was so high when the needles are set so rich. Once you get the break in done and start fine tuning it, the motor will perform much better. Finish your break in and start the fine tuning, then if you still have idle problems you can start looking for other causes. Do you have a temp gun?
- Thread starter
- #13
thanks for your advise, i'd just install my on board temp tonight..i will go through my 3rd tank tomorrow so i will keep you informed...when you turn completely the idle screw counter clock... the opening on the carb is fully close?
MrClean
Hardcore RCTalk User
Yes, counter clockwise on the idle setting will close the slide valve.
MrClean
Hardcore RCTalk User
It won't close completely, it would always stall if it did. You want a small gap there at idle (about the thickness of a credit card).
- Thread starter
- #17
i'm back from my third et fourth tank, is much easier to start now....
3rd tank: the LSN needle are set flush with the body...the temp goes max 273F... the engine cut sometime during acceleration...
4 tank: the acceleration still very sluggish but half throttle to full... sound better...but during first couple of run the engine cut after the full throttle....so i'd open a little bit on HSN ....but the temp was only showing 220-230 max...plenty of blue smoke at full throttle but less during acceleration
2 flip happend.... i was on tarmac... i brake and turn same time :\... nothing bad happend
i don't know if it is normal that when i hit WOT...and during the moment that i brake ...the rpm stay at high rpm few second before it drop to a correct idle
can't wait to finish the break in... i want to go off road so bad
3rd tank: the LSN needle are set flush with the body...the temp goes max 273F... the engine cut sometime during acceleration...
4 tank: the acceleration still very sluggish but half throttle to full... sound better...but during first couple of run the engine cut after the full throttle....so i'd open a little bit on HSN ....but the temp was only showing 220-230 max...plenty of blue smoke at full throttle but less during acceleration
2 flip happend.... i was on tarmac... i brake and turn same time :\... nothing bad happend
i don't know if it is normal that when i hit WOT...and during the moment that i brake ...the rpm stay at high rpm few second before it drop to a correct idle
can't wait to finish the break in... i want to go off road so bad
MrClean
Hardcore RCTalk User
Looks like your temps were decent during the break-in. I look at it like this, break-ins can be a real pain in the a**, as long as you're not overheating the engine (and it sounds like you didn't) don't be too concerned with how it's running. The motor is still really tight and it's running pretty rich. Once your done breaking it in, then you can start being concerned with how it's running.
I believe the high rpms after a WOT run is not unusal on a motor that is running on the rich side. At WOT you are pumping the maximum amount of fuel into the motor and when you let off the throttle, it takes a second for the extra fuel to burn off. Once it does, the idle will settle back down to where it should be. This type of problem is something you should see slowly disappear once you start dialing in the tune.
Generally, the trail of smoke will only occur at the upper end of the throttle, when the highest amount of fuel is going into the motor.
I believe the high rpms after a WOT run is not unusal on a motor that is running on the rich side. At WOT you are pumping the maximum amount of fuel into the motor and when you let off the throttle, it takes a second for the extra fuel to burn off. Once it does, the idle will settle back down to where it should be. This type of problem is something you should see slowly disappear once you start dialing in the tune.
Generally, the trail of smoke will only occur at the upper end of the throttle, when the highest amount of fuel is going into the motor.
MrClean
Hardcore RCTalk User
I don't keep it for very long. I will if I'm going to run it within the next couple of days. I run O'Donnels and it starts out clear, if you leave it in the bottle for awhile, it'll start to turn yellow. Not sure exactly what that means but I'd rather not use it. Just make sure you keep the rubber stopper on it.
