How this look? normal or replacement

Looks like oil buildup, but if it has compression it should be good.

It's hard for me to tell, but it looks okay. If you could get a top-down view that was more in focus, I could probably see what's going on better.

Test the compression by rotating your flywheel on turn over. If it becomes relatively hard to turn, then the compression should be okay. If it isn't, then your compression probably isn't. If you can't come to a conclusion, then heat your engine up (any way that you can, be that a hairdryer or just running it) and try it again. I singed my finger on my flywheel, so watch out... And yes, my engine had overheated when this happened. That should allow you to come to a conclusion about your engine. If you remember how it ran when it was new, and it doesn't run near as well when it was new now, then I'd say it's time for a replacement. If you're going to keep the same engine, why don't you go ahead and buy a piston and sleeve and replace it when you see fit? I don't think they're all that expensive. I can't tell what engine you have, but you probably can find the piston and sleeve for it on TowerHobbies somewhere... Might want to check it out.

Hope that helps.

Compression=Yes

so now i think i hjust dont know how to tune it


Can someone link me on how to get a engine running right with smoke and everything i just dont know how to tune my LSN!

You tune your LSN using two methods that I know of. I use the first one I'm about to tell you, but some people don't like it.

The first method is to get your engine up to running temperature (make sure you've set your HSN well before messing with the LSN too), pinch the fuel line going from the tank to the carburetor. The engine should idle for a few seconds (2-4 seconds), rev up, and then settle down and die.

The second method, which I believe isn't quite as accurate, is to get your engine up to running temperature, then let it idle for about 10-15 seconds, then immediately punch the throttle. If your engine gurgles like it is running too rich then either stalls or takes a while to get going, then your LSN is too lean. If you do the same thing, and right after you punch it then engine shuts off without gurgling at all, then your LSN is too lean.

Hope that helps.

Ok its dark now but ill post tomm.!

wheres a starting point tho? i cant get it too run without it set somewhat good

What engine are you running? Is it the stock one? If it is, the stock one on the Evader (I'm just guessing since your forum-name is Evaderstbasher) will probably be flush with the carburetor body. I couldn't find anything about it, but a lot of engines have this setting. Give that a shot and see if it'll crank up.

Engine internals can get MUCH worse than that before it really means anything serious. If you have an old lawnmower, pull the head off and you'll see what I mean. Low quality or old fuel will cause oil to build up on a piston surface. Most engines, even perfectly tuned ones, will get dirty inside to some degree.

Initial settings From Hobby Services:
The initial settings for the carburetor of your DuraTrax .18 engine are easy to set.

First, close the high-speed needle valve and open it 2-1/4 turns out from closed. This is the initial setting, and is a rich setting. You will have to lean the engine from this point as you drive the car.

To set the idle mixture needle, which is the grey screw in the center of the throttle arm, inside the chrome barrel, you must be able to see into the carburetor. Remove the air cleaner from the carb so you can see what you are doing.

Open the throttle to the full-open position. Inside, you can see the idle needle and the fuel nozzle. Adjust the idle mixture screw until you have a gap of 2mm to 3mm between the needle and the nozzle when the carburetor is fully opened. You double-check this by looking at the head of the idle mixture screw. It should be sticking out of the chromed barrel by about 1/32". This is an initial setting, and is a bit rich.

When you start the car, you can leave the clip-on battery attached to the glow plug for some initial running. As you run the car, it will be a bit rough. Adjust the high-speed needle until it just stops running rough. You can then adjust the idle mixture needle and the carburetor throttle opening until you can have the car stopped, but with the engine running smoothly. If you release the brake or stop holding onto the car, it may tend to ease forwards, just like a full-size automobile with an automatic transmission. This tells you that you have the correct setting.

Now go out and enjoy running your R/C gas car with your DuraTrax engine!

I have a question about the Low Speed needle...

I get the High one set properly, but my car doesn't accelerate sharply, I know it's a Low Speed problem, so I start to play with the LS Screw, but then, the engine temperature on idle starts to get up and up and up.. Any one has an idea ? is it because it's too lean on Low end, or I shouldn't care about that and run it with the low end rising the temp ? I don't know if it rises the "running" temperature, because I didn't want to screw my engine...

The engine is a Nitro Star .15SS....

Thanks a lot!

My engine (Nitro Star T-15) has a weird thing about idling. When it comes in from a high-speed run, and idles, it will heat up quickly for a few seconds (around 10 or so) and then start going down. It usually drops about 30 degrees in a couple minutes (yes, and I don't know how, but my engine will idle that long). Wait a while while it is idling next time and see if it goes back down after a minute or so, unless it gets into the Danger Zone (1980's overdriven guitar starts playing in the background ). I believe our two engine are quite similar.

I had a problem with my 2.5 engine with that, but it turned out that the idle was too high. It was my first engine so I had nothing to compare it to, and then I went online and heard how it was supposed to sound at idle. I fixed the temperature at idle problem by richening the LSN a bit and drastically lowering the ISS.

Hope that helps.

I'll keep that in mind next time I run it... Thanks!

You're welcome. Let us know how it goes.

this is the way mt fantom .15 looked like after 6 gallons and a couple mistake lean runs [:@]

your getting there

Well, it happens... Is that an old picture or is that the way it is currently? It definitely looks like it lost some compression...

that was when it wouldnt run any more at all
i just rebuilt it a little short of a gallon ago [8D]

here is another pic

well the past 10-15 tanks i was running it so Rich i got like 5 min run times but i got it set up fine now im now thrue the blue thunder i have 325cc left then on to a little less oil content so im going to need to have it tuned just right some times i think i run it to lean and sometimes i think its fine i need a temp Gage so i can protect my motor and also i need to burn up my motor so i can get a new piston sleeve the get a .15 or .12 depends if i want to race? but when i move dono if there will be more tracks that hold races and if so i will get the .12
here is the piston sleve i check them off and on check how its doing eather 1/2 a gallon or every glow plug i take the head off and check but thats just me
eye candy

As a matter of fact, I haven't had any reason to take off the cooling head on my engine, but I need to clean it so I'm going to go do that now. It needs a good scrubdown, there are a few specks of dirt on it...

Looks good Brownstone.

thanks i like the bowties they work good up front if your shocks are set good