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ashman

RC Newbie
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I just got a new engine and it has bin running great but i noticed that there was fule leaking out of it. Is this normal. I had seen it happen on some of my other engines. The fuel is leaking out from under the heatsink. I think.:\
 
Umm, I've never heard its leaking from under heatsink matbe u gotta crack in the crank case.. Other than that tighten your glow plug, and i would make sure you dont have a cut in your fuel line . Are you sure its nto a crack in the fuel line close to the heatsink??
Check that
Keep us posted.
 
If it floods this can occur. If it keeps doing it and gives you a hard time tuning it, replace the head shims. If that does not get it then there is an issue with the sleeve and engine block sealing together. In this case it is a warranty item. You'll need to send it to HPI.
 
i think i foud the issue and its not what i thought. I think it was because the silicone sleave on the exaust had a tear in it an it was blowing it back on the engine
 
i think i foud the issue and its not what i thought. I think it was because the silicone sleave on the exaust had a tear in it an it was blowing it back on the engine

Yeah, that will cause a mess that is sometimes hard to chase down.

You might find that drilling a new set of holes in the flange of the header and running two springs helps make the gasket last longer. I did that on my aftershock because it liked chewing up gaskets and making a mess in a very short time. I haven't had much of an issue since I added new holes and an extra header spring.
 
Make sure when you install your exhaust that evrything is "square". If the header sits crooked on the exhaust port it will cut into the gaskets.
 
Alright, I'm HAVING THE SAME PROBLEM!! I dont know what it is, I'm gonna have to take of the heatsink. Damn, i was just about to go out and bash and i look on my driveway i had like a puddle of nitro, i looked and it spitting from right underneath the heatsink

but its definetly not coming from the exaust. I checked i do have washer underneath the glowplug, its tight too, I'm not ure what it is
 
Make sure when you install your exhaust that evrything is "square". If the header sits crooked on the exhaust port it will cut into the gaskets.

This is correct. I had that problem with my Nitro touring car. Make sure the pipe mount is not pulling the pipe off the exhaust port. The pipe mount should support the pipe in the position it naturally sits in. Do not allow the pipe mount to pull the pipe. (that sounded funny).
 
Is this one of the HPI 4.6 engines? I have seen them blow the head gaskets/shims.
They also come set way too rich from the factory. Lean both the needles some and retry it.
Some of the 4.6 engines I have broke in would be so rich on top end that it could not move the truck. This is not good for an engine. If it is overly rich, all that excess fuel is going to find a way out of the engine.
Try a new glow plug, yours may not be sealing.
Pull the 4 bolts off the head and inspect the head button. You will be able to clearly see where the leak is if a shim is causing the leak. The shims are cheap BTW.
 
Well, i took off the head, and there are no signs of wear, i looked at the glow plug it looks fine although i havent changed it for a l[ong while. Umm, its not rich, imean it maybe a little on the rich side but not rich as in when it comes from factory, would you havea pic of NORMAL headshims and waht they should look like?>
 
DOES Anyone have a link online for Engine shims for my nitro star f4.6 engine? Cuz i honestly done know why its still leaking.
Any help guys..
 
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