Nitro engine leaks

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Sebkauff

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I'm new to nitro so I need some help. About a week ago I was running my nitro buggy and 1: it was pretty hard to start but it ran fine for a bit, second time starting it it was very hard to start but I got it started. It died pretty fast and when I got the body off I noticed there was fuel everywhere. I did some research and came to the conclusion that the high speed needle housing was loose. I tightened it up a bit and went to test the car but it wont start. Turns out the glow plug was dead. So i ordered more glow plugs and after about a week they finally turned up. The buggy started no problem but it was making an odd noise. So I watch it as it idles and I see little spurts of fuel coming from somewhere near the head. i could see drips flying onto the exhaust springs and chasis. what could be leaking???? And how do i fix it?

Thanks!
 
I'm new to nitro so I need some help. About a week ago I was running my nitro buggy and 1: it was pretty hard to start but it ran fine for a bit, second time starting it it was very hard to start but I got it started. It died pretty fast and when I got the body off I noticed there was fuel everywhere. I did some research and came to the conclusion that the high speed needle housing was loose. I tightened it up a bit and went to test the car but it wont start. Turns out the glow plug was dead. So i ordered more glow plugs and after about a week they finally turned up. The buggy started no problem but it was making an odd noise. So I watch it as it idles and I see little spurts of fuel coming from somewhere near the head. i could see drips flying onto the exhaust springs and chasis. what could be leaking???? And how do i fix it?

Thanks!
I have no nitro experience but, make sure the head is tightened down, tighten it in a star pattern. DON’T OVER-TIGHTEN IT!
 
Is the glow plug all the way in?
 
If its around the fly wheel, Id say front or rear bearings or bushings.

How I was taught was to remove the engine, air filter, and clutch assembly. Instal a fuel line on the carb. Cover carb top and exhaust, submerge in water and blow. The air should bead out the area.

If its those, usually an oven warm up expands everything to put new ones in.

If its dripping clear, maybe a head shim or carb gasket?

If its darker, exhaust gasket, and if its oily the rear bearing that the one way is on.

How much tension is on the exhaust springs?
 
The leak is above the carb. And the engine has only had about 15 tanks through it. But I'll check that. The fuel doesn't seem discolored at all. And it doesn't seem like there is to much tension on the exhaust springs
 
Yes. The leak seems to be coming from just below the head
Whats up bud? So did you ever take off the head?. Is it new or used? Sounds like if the head gasket is missing or broken. The hard starts are called cold start. Which isn't good for the engine. You really should be useing a heat gun or a head warmer. To warm up the engine before you try to start it.. should never start a nitro engine cold... that also could have been the problem. Could have cracked the casing or the cooling head..
 
Yes, I have taken off the head before. I got it new. How often do you replace head gaskets? I was using a head warmer, which is why I was concerned when it was hard to start
 
Yes, I have taken off the head before. I got it new. How often do you replace head gaskets? I was using a head warmer, which is why I was concerned when it was hard to start
How long did you keep the warmer on for. Should get it up around 200° before trying to start.. I like the heat gun get a better all around heat up.. you don't really need to replace it. Is it in I've forgotten it from time to time. Or did it get bent kinked..
 
Head warmers take awhile to get the engine warm. Need to heat up the head then in transfers down to the casing /block. Heat guns are faster. And better if you are near electric. I always use heat gun at house. Fire it up and let run for a little bit. Then go out to bash area. It also could have been flooded. When you tried to start it. You said it was leaking from under head. Did you make sure the head was tight. And you tighten it in a start pattern. Not just tighten one side then the other could crack heads that way. Always in a star and little bit at a time
probably 5-10 minutes. yes it's in. It doesn't look damaged, maybe a little corroded/dirty. is that normal?
Do you have a temp gun?
5 -10 mins probably not long enough bud
 

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Ok, I'll let it heat for longer next time. Yeah, I triple checked the head. And tightened it in a star patter when I put it back on (after checking the gasket)
 
Ok, I'll let it heat for longer next time. Yeah, I triple checked the head. And tightened it in a star patter when I put it back on (after checking the gasket)
And the washer is under the plug?
Your fuel lines all good. No tiny holes or cuts?
 
Air filter is on the carb tight. If not wrap it up with zip tie
 
Yep. Also yes I do have a temp gun
Ok cool. So you want the casing and base of head by plug hole around 200° .. also do you keep you piston down at the bottom. So BDC
Bottom dead center. You want to keep the piston at the bottom. While the engine cools. That also could add to the hard start
 
If the engine cools while the piston. Is at the top of stroke. Could lock up the piston. Which in return lock up engine completely or make it very hard to start... want the piston down out of the sleve. While your not running it. So the sleeve can cool properly..
 
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