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Revo 2.5R - Won't cool down

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Blackbird85

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Help please. I have a Revo 2.5R engine that I can't get to cool down. It has a great pinch, ton's of compression, awesome power and I get ton's of smoke when I run it. Temps quickly creap up to 270-290 no matter what I do for tuning and it stalls out all the time when I bring it in for a temp check.

Other engines run sweet around 220 so I know it's not my temp gun.

Any ideas? I was thinking an air leak but wouldn't that cause heat cause it's lean. I really don't think it's lean cause I get lots of smoke and dripping fuel out of the exhaust. The driveway gets plenty of drippings on it when I am running it.

Thanks in advance for your ideas.
 
Chances are you're adjusting the HSN to bring the temp down. If you don't have a leak in the system, It's the LSN that needs to be richened.
 
it sounds like you have an air leak somewhere, seal up your engine, get a new tank and fuel line
go back to the factory settings and go from there
 
Looks like it was an air leak. Sealed everything up with sensor safe high temp RTV and it stays cool and holds a tune much better. Thanks guys. Those airleaks can be tricky. No idea where it was but I guess it's gone now.
 
There is no proper temp for any motor. It can depend on so many variables you can't say what an ideal temp is. I live in an area (mid-west) where it's hot and very humid in the summer time. My 3.3 will run between 240 and 270 degrees depending on the weather that day. If it starts to get any hotter than that, I'll richer the HSN a smidge to help lower it a bit. (that is if you already have a properly tuned LSN). I've heard other guys say theirs runs awesome between 200 and 220. I also take note of where they live, usually on the west coast where it's not nearly as humid and their motors will be tuned a little richer due to the weather conditions. Temps should only be used as a guideline with other factors taken into consideration..... wot performance, smoke, and the LSN 'pinched-fuel line-test'. All this is stuff I've read and what has worked for me, you will find different things that'll help you develop the skills needed to properly tune an engine. (I'm still learning and probably always will be)

Clear as mud now? LOL
 
I know it sounds complicated but he's exactly right. A good starting point would probably be in the 220 to 240 range, and once you get used to the motor you'll be able to feel it out and tune from there. With my first nitro, I learned to tune with the temp gun. But once I got used to the motor, I could pretty much tell where it was running. I still used my temp gun to guarantee accuracy, but I could pretty much tell when I needed to adjust the tune by how she was running.
 
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