Revo engine links oil

[lovemyrcnitro]

I have a Traxxas Revo 3.3.when it idles it drips oil enough to form a puddle,it is a little sluggish when u start out and then runs great.I'm newbie and I don't think this is normal.I just got the truck so I only ran one tank thru it and stopped when I noticed the idle drip.Thanks in advance.

 

[Childresshunt]

Was the truck brand new and did u break in?

 

[Non Crimen]

You probably have a leak in-between the manifold and engine itself. I really hope you did a proper break in


Sent from my Pipboy-3000 in the Capital Wasteland.

 

[EXTREME1]

where is the oil dripping from?front or rear of engine?imo clean the engine good with purple power and tooth brush then crank it and let it idle to see where it is leaking oil from.what are your temps after running it for a tank?how do you have your hsn,lsn set?

 

[lovemyrcnitro]

The engine was broken in right.The oil drips from the exhaust pipe not the motor.The truck is not new.I just got it.The truck runs great it just drips oil at idle from the exhaust pipe.

 

[EXTREME1]

sounds like it's to rich.here are the factory carb settings.
High-Speed needle

TRX 2.5, TRX 2.5R, and TRX 3.3 Racing Engines:
A good starting point for the high-speed needle
is 4 turns out (counter-clockwise) from closed.

Low-Speed Needle

Notice the thin darker gray area between the low speed needle and the throttle arm. This is actually the other end of the slide valve from inside the carburetor. The low-speed needle is threaded into the slide valve and is set flush (even) with the edge of the slide valve.

Note: This is a good base setting. Adjustments may
need to be made to the low-speed needle for best
performance in your running conditions.

Idle Stop Screw Idle Gap

The idle stop screw controls the idle speed by preventing the carburetor slide from closing completely. Turn right (clockwise) to increase idle, and left (counter-clockwise) to decrease idle. A good starting point for the slide valve to stop at idle is a 0.7mm-1.0mm gap.

 

[lovemyrcnitro]

I haven't touched the Lsn,hsn or the idle screws,it idles just fine.The temps are normal,just drips oil out the exhaust .

---------- Post added at 12:51 PM ---------- Previous post was at 12:46 PM ----------

Thank You Extreme I will give it at try.

 

[andydrew39219]

Are you sure your not just running rich and you see unburned fuel coming out of the exhaust? If I start my pede and let it idle for 25 seconds on my porch it leaves a good oily mark where it was exhausting. My pede is just rich and spitting out unburned fuel.

I am kinda confused by what your saying though. Leaking is kinda implying that oil/fuel is coming out of a place it shouldn't be. If your exhaust is just spitting out a little bit of fuel/oil then it's probably just rich. Running your engine rich is good for it as well.

 

[Non Crimen]

What does the smoke trail look like?


Sent from my Pipboy-3000 in the Capital Wasteland.

 

[2revo1maxx]

Your engine is supposed to put out oil, if you're happy with the way it runs then leave it alone.

 

[lovemyrcnitro]

The smoke trail is normal.The drip is coming out of the exhausting port.Not spitting fuel just dripping solid drips of clear or murky oil,no fuel.Like I said it runs like a bat out of hell and idles just fine.

 

[andydrew39219]

It sounds just fine to me. As long as you have good temps, the engine runs fine (no bogging/stalling/ect) and you have plenty of smoke throughout the powerband of the motor then its good.

 

[wacmartin]

I personally think your tune is to rich as well. What fuel do you run what's the color of it compared to the "oil" drip from your exhaust? You said it's sluggish to start, probably cause it's loading up with fuel and when you hit the throttle you're clearing out unburnt fuel and that's what's leaking out of your exhaust. I'd say you need to lean out the lsn, search the fuel pinch test on here or Google. Or maybe set the needles back to factory settings and look up the nitro tuning guide in the stickies in the nitro section on here.

 

[andydrew39219]

I think it depends on how bad the bog is. Is this like start and idle for 30 seconds then if you blip the throttle a couple times it snaps out of it? or is this a bog so bad that it won't even budge unless your WOT?

If it's just a little boggy from idling and you can blip it a couple times and it's not boggy anymore I would say that's pretty good. As in rich but not too rich. But correct me if I'm wrong guys.

 

[wacmartin]

A bog is a bog! Wouldn't you want your tune so that it doesn't bog down at all and just snaps off the line? After your initial tune is completed and all you have to really tune is the hsn for ambient temps, you should want your truck to idle for however long without loading up on fuel. I've only been doing this for 2 years so there's a lot i don't know still but that's what I went for when tuning my lsn. So please someone correct me if I'm wrong.

The lsn is what controls the amount of fuel getting to the motor at low speeds/idle, wouldn't you want just enough to keep it running and not to much that it's just loading up with fuel that you have to blip the throttle to clear it out? Now I understand that that's something that needs to be done during break in and initial tuning, but shouldn't really be necessary when the motor is broken in and tuned to optimal performance. But then again that's how I understood it and went for.

Then again the OP's problem could be something entirely different, I'm just stating what I would check first seeing as how he said he's never touched the needles and that's a symptom of a rich tuned motor.

P.S. I think I'm forgetting to add something, I'll edit later if I remember.

 

[2revo1maxx]

You probably have what's known as a 'false tune'. A false tune is when your LSN is a little rich, but the engine seems to perform well because the HSN IS LEAN. Dark, murky oil residue can be from running slightly lean, although oil dripping from the stinger is still a good sign.
If I were you, I'd richen the hsn until you know for sure that it's too rich in the high rpms, then slowly lean it back to performance. If done right, you can temporarily eliminate the HSN from the equation.
The next step is to do this:

https://www.rcnitrotalk.com/forum/showthread.php?t=94326

 

[wacmartin]

Interesting! That's something I'm going to try in the spring, I don't race nitro at all or offroad much but always trying to get the most out of truck with the stock motor. Now one thing, is it going to fire up easy like it always does with closing off the idle gap that much at once. Cause when setting my idle gap the first time it was pain to start if I closed it up just a little bit, but that was also before I got a optimal tune. Or. If I'm understanding this correct should I lean the lsn a bit before closing the gap to .5mm? Or do you think it will fire up at .5mm then adjust the lsn?

 

[2revo1maxx]

.5 mm may be a little extreme for some engines, but if the lsn is set properly it will start.

 

[EXTREME1]

i use a paper clip to set my idle gap and that seems to work very good.

 

[lovemyrcnitro]

Thanks you guys!!
I got it running great,no bog and no oil drip,just spits out the exhaust like it's should.

"THANKS FOR ALL THE HELP"