engine stalling

[josh1993]

Hi there

I have a force .21 engine and when I take it on grass it doesn't like it and the engine stalls Anybody know why it is doing this and what I could do to stop it happening?

many thanks
Josh.

 

[MotoGod]

Need more details. Is the throttle wide open when it stalls?....is it idling in the grass? Does it sound like it's working too hard and stalling? Have you checked your clutch lately?

 

[josh1993]

it idles on grass, then stalls when you touch the throttle. it doesn't sound like its working to hard, it just cuts out. I have looked at my clutch and it seems okay, it is keeping a good connection with the clutch bell.

another thing: my car seems to randomly stall on the tarmac. The tarmac is smooth and is level ground. It could happen any time - with or without any throttle. However this doesn't happen very often but when it does it refuses to start unless you leave it for a few minutes... then starts first time. Do you know what could be the problem?

thanks
Josh

 

[alien13]

Your tune maybe? Too rich/lean? When I was tuning mine I had that issue, but it went away as I leaned it out. I know you said you checked your clutch, but maybe the spring is worn, not as tight as it should be, causing to to engage too soon?

 

[Metalhead Matt]

Your running lean. The reason that it doesn't start right back up is that the fuel's boiling in the carb. Richen it up until it starts to run crappy, then lean it again until runs right. Drive for a few minutes in between adjustments. Don't tune the engine until it's warmed up. Adjust the needles in 1 hour increments. If you don't have a temp gun, it should be your next purchase.

 

[josh1993]

ok thanks guys for your advice. I will richen it up and lean it out again. when doing this I only alter the HSN right? If my car is creeping forward slightly when idling does that mean I am running it too rich?? or too lean??
No I don't have a temperature gun, I will try and buy one soon.... what is an RC car engines running temperature roughly?

thanks
Josh.

 

[alien13]

ok thanks guys for your advice. I will richen it up and lean it out again. when doing this I only alter the HSN right? If my car is creeping forward slightly when idling does that mean I am running it too rich?? or too lean??
No I don't have a temperature gun, I will try and buy one soon.... what is an RC car engines running temperature roughly?

thanks
Josh.

It varies by engine. My Losi .20 is supposed to run between 190 and 220f, and my OFNA .32 is supposed to run 210 to 250f (ish)

 

[josh1993]

oh right, okay. my engine is a OFNA force .21

i used to have am OFNA .32 too, but it broke and could only afford the one I have now.

 

[Metalhead Matt]

You'll need to adjust both needles. Get a good top end with the hsn. After your satisfied with your hsn adjustment(good top speed and good smoke stream), then do the pinch test. After a high speed pass, pinch your fuel line as close to the carb as you can. It should take 2-3 seconds to rev and die. Any more, it's rich. Less=lean. Only adjust a little at a time(1 hour increments) and drive for a few minutes in between adjustments.

 

[josh1993]

thanks Metalhead Matt thats very helpful. I will do that test and get back to you. You have any idea why the engine randomly stalls??

 

[Metalhead Matt]

It's stalling because of the tune. Hard telling if it's lean or rich from the the info above. A way of testing the engines temp is by putting a couple drops of spit on the head. It should take 4-5 seconds for it to evaporate. Let us know how it goes tuning and with the temps. Remember, you may have to raise the idle after you richen the lsn. My gut's telling me your lean, so by richening the lsn, you'll lower the idle. Leaning the lsn will raise the idle. Let us know how it goes and we'll do some more pin-pointing.

 

[josh1993]

Hi, I must say thanks very much to Metalhead Matt. What you said was spot on! I did what you said and the engine runs so much better, doesn't stall like before. I richened the HSN out to a tidy place and when doing the pinch test it took roughly 2 seconds for the engine to rev up and cut out.
There is one thing though. I have also richened the LSN (after richening the HSN) and it still wants to slightly creep forward when idling. Might be a stupid question, but do I just richen it more until it stops creeping forward??
Hopefully tomorrow I will run it on some grass and then see whether it stalls or not. I have a nice blue coloured smoke stream from the exhaust now whereas before there was barely anything. I'm glad its better now, I was running it very lean, sounds like I would have ruined the engine pretty soon. The engine is also running at a higher temperature now, you can feel the heat coming off it. I put some spit on it and it took about 3 to 4 seconds to evaporate.
Many thanks....
Josh