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engine flames out when hot then hard to start. whats wrong?

engine flames out when hot then hard to start. whats wrong?

Old 09-19-2011, 02:14 PM
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Default engine flames out when hot then hard to start. whats wrong?

the engine flames out when it gets hot and flames out then it is hard to start until it cools down. does it need a rebuild? or what?
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Old 09-19-2011, 02:17 PM
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Sounds like your piston and sleeve are worn out and.have.no.compression
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Old 09-19-2011, 02:26 PM
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I agree, the most likely candidate is a engine that's worn itself out. I'd recommend a new motor over a new piston and sleeve since you'll also get new bearings, con rod, etc. but a rebuild will save you a bit of cash.
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Old 09-19-2011, 02:55 PM
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Could be your tune. Is your LSN lean enough and idle screw set to run a .5, .6mm gap?

I don't recommend a new anything if thats not the problem. I do however recommend a pinch. Best $20 you can spend in this game IMO!
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Old 09-19-2011, 05:21 PM
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Is the engine too lean and over heating?Its hard to find the problem without seeing the engine.If it has good compression then its tune is off.Probably too lean and overheating causing it to vapor lock.
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Old 09-19-2011, 06:02 PM
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or vapor lock
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Old 09-22-2011, 11:09 AM
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+1 if the compression is strong the engine could be overheating due to an air leak or lean cindition which would cause it to not start until it cools down. Also the compression could be weak and when the engine gets up to temp the metals are fully expanded and compression gets even weaker and it will not want to stay running.

Check your compression first if its strong, check your tuning or check for an air leak. If the compression is weak that may be the problem right there.


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Old 09-22-2011, 11:23 AM
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thanks guys, it has good compression when its cool but when it gets hot it losses compression. would getting the sleeve pinched help?
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Old 09-22-2011, 05:25 PM
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a pinch will help if there is no scratches on the piston or sleeve
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Old 09-22-2011, 06:57 PM
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happened to one of my cheap rtr engine before when i was starting out RC. it turns out that the carby gets too hot and vaporizes the fuel as it enters it. So no fuel can enter the combustion chamber. at least that was my conclusion.

When it happen again, try and spray things like motor spray/ nitro cleaner/ or even methylated spirit all around the carb concentrating on the carb nipple. If it starts, then you know what the problem might be.
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Old 09-22-2011, 07:04 PM
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Originally Posted by Losimoe View Post

When it happen again, try and spray things like motor spray/ nitro cleaner/ or even methylated spirit all around the carb concentrating on the carb nipple. If it starts, then you know what the problem might be.
I believe that just means your carb is loose, just tighten it, or seal it if it is really leaking.
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Old 09-25-2011, 07:08 PM
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Originally Posted by schmoey View Post
thanks guys, it has good compression when its cool but when it gets hot it losses compression. would getting the sleeve pinched help?


Yes, if the compression is low a "pinch" or resizing will correct that and get it back to like new compression and seal.. Check out our website for more info.



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Old 09-25-2011, 07:12 PM
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Originally Posted by schmoey View Post
the engine flames out when it gets hot and flames out then it is hard to start until it cools down. does it need a rebuild? or what?
lance can hook ya up!

Originally Posted by Rcrenew View Post
Yes, if the compression is low a "pinch" or resizing will correct that and get it back to like new compression and seal.. Check out our website for more info.



Lance,
RcRenew.com
sounds like a pinch is in the future to me.
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Old 09-25-2011, 08:40 PM
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Originally Posted by schmoey View Post
thanks guys, it has good compression when its cool but when it gets hot it losses compression. would getting the sleeve pinched help?
If you have the time to wait between race days get a hold of Lance at RCRENEW.com he can hook you up with what you need. He has A+ customer service. See what he says maybe send him your motor to look at and he will let you know that same day.
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Old 09-25-2011, 08:45 PM
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Originally Posted by schmoey View Post
the engine flames out when it gets hot and flames out then it is hard to start until it cools down. does it need a rebuild? or what?
What brand/size of engine do you have?
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