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Old 05-31-2010, 10:24 PM   #31
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Am I the only one that is curious what is *actually* wrong with this engine? haha.

Seriously; I've yet to understand because the sleeve isn't supposed to move at all.

If you're turning the crankshaft and the piston "stops moving"...and something is broken...then you're either going to feel it bind and never move again or it will slowly start coming back down.

The piston "lags" in position over top dead center...it looks like it holds still for quite a while.

The noise that it's making, is it sqeeking and very hard to turn at the same time?

I'm with Houston on this one, sounds like you need to preheat it and start over.

A fun animation; not quite our exact setup but I'm sure most will get the idea...

http://www.animatedengines.com/twostroke.shtml

And just for those that need a real basic rundown, watch the video series (not saying all content is correct, but hey, it's pretty good for those that need to learn).

http://www.youtube.com/watch?v=UTIINXvzi5s
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Old 06-01-2010, 03:33 AM   #32
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So what you are telling me is that the Novarossi 4C it's normal that when i start spinning the engine, when the piston gets to the top there is soo much pinch that when you keep spinning the crankshaft the cylinder stops moving???
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Old 06-01-2010, 05:04 AM   #33
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So what you are telling me is that the Novarossi 4C it's normal that when i start spinning the engine, when the piston gets to the top there is soo much pinch that when you keep spinning the crankshaft the cylinder stops moving???
The piston will appear to pause at the top and it will be VERY difficult to turn the crankshaft, and then it will start heading down.

Coincidently this is why you should always disassemble, inspect and thouroghly clean every new engine before running/breaking in. I have found all kinds of crap in brand new engines that were factory sealed. Metal shavings left over from the manufacturing process are sometimes present(NovaRossi and O.S.), plus I have found a broken wristpin retaining clip on a Picco. If you fire up the motor with this stuff in there you can seriously damage the piston and sleeve. If you don't know how to disassemble a motor then take it to the hobby shop where you purchased it, or the track that you race at and have someone help you.
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Old 06-01-2010, 08:16 AM   #34
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Take the engine to your local hobby shop or local track and ask someone to help out. Then if there is a problem contact customer service.
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Old 06-01-2010, 08:36 AM   #35
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So what you are telling me is that the Novarossi 4C it's normal that when i start spinning the engine, when the piston gets to the top there is soo much pinch that when you keep spinning the crankshaft the cylinder stops moving???
I think you're confusing the names of the engine parts. I think you mean the "piston" will stop moving as it nears the top of the cylinder. Yes, that's normal. The top of the cylinder is tapered and when the engine is new, the piston will get stuck in the top of the sleeve (or cylinder) until you get the engine started and broken in, and possibly for some time after.

It's not a crime to admit how much (or how little) experience you have with nitro engines. When someone asks you, it's because they know what not to suggest if you have have a certain level of experience. If you don't have any experience, which I suspect is closer to the truth, then everyone knows to cover the basics with you. You don't have to be defensive - just be honest and everyone will know better how to help you.
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Old 06-01-2010, 08:46 AM   #36
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So what you are telling me is that the Novarossi 4C it's normal that when i start spinning the engine, when the piston gets to the top there is soo much pinch that when you keep spinning the crankshaft the cylinder stops moving???
Yes. That's also true for any good engine.
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Old 06-01-2010, 10:22 AM   #37
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I believe it was already mentioned but I'd like to reiterate - check to make sure your flywheel is tightened properly. If not, when the piston reaches the pinch zone it'll get very hard to continue turning the crankshaft. If you're applying a lot of pressure to the flywheel and it's not tight, it can actually slip on the crankshaft. This will make it appear as though you're turning the crankshaft and the piston isn't moving, which isn't the case. You should also feel and hear the flywheel grinding on the brass crankshaft bushing, which may explain the noise you're hearing.

Hope this helps.
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Old 06-01-2010, 04:47 PM   #38
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Douglas what I think they are trying to say is if you haven't delt with or have any idea on a certain subject, its best to keep your mouth shut before you make yourself look like a total idiot.

But feel free to post whatever you want.
ok u got a point.
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Old 06-01-2010, 04:59 PM   #39
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You know it's a good idea to learn some engine basics and terms. It will help
us help you. Novarossi's are one of the very best R/C car engines. A sleeve/
cylinder never moves. How old are you?
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Old 06-01-2010, 05:10 PM   #40
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I am 16 and i am half german half italian, i always get confused but i do know the basics, I know the terms in Italian but I need to learn them better in english.
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Old 06-01-2010, 05:22 PM   #41
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I am 16 and i am half german half italian, i always get confused but i do know the basics, I know the terms in Italian but I need to learn them better in english.
So you are saying that the sleeve/cylinder is broken; By that you mean the sleeve is broken in two at the ports before you even started it?
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Old 06-01-2010, 06:04 PM   #42
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Sounds like it's just terminology that's causing the confusion. Yes, these things are SUPER TIGHT when new. The piston will stop at top dead center and you will still be able to turn the crank a few degrees before it starts going back down and it will make a god awful squeaking noise.

Warm it up before trying to start it, use a strong starter box, run a LOT of fuel through it before you start standing on it and be patient. They can be a royal pain when new but proper break-in will reward you with a fantastic engine.

Oh, and you might want to replace the rod after the first gallon, most of which will be needed just to break it in.
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