Performance tuning, let the engine tell you.

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I knew it was rich by the amount of fuel coming out. I was just wondering if that alone would cause it to run this way? I did set all needle to "factory settings" and changed glow plugs also, i didnt mention that before. I went from an 8 plug to a 5, b/c off the temps my gun was reading. i have read since then that i should tune to smoke/sound not temps, so that was what i was gonna try. but wont idle.
 
Help if ya can

My xl 5.9 motor crackles wondering why maybe you can help? Also when i let off the throttle it seems to rev. Kinda like you said would be too lean. Ready to change engines. yes or no
 
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Re-read the directions and tune according to them, not sure what els to say.
 
First guess would be that the HSN is too lean. I think it can cackle if the LSN is too lean also but the high idle after you let off points to being lean on the HSN. Is the motor broken in? Was it broken in properly? You should start over at factory settings. The LSN and MSN should be flush to the carb body and the HSN has a groove in the brass body. The plastic thumb screw part should be even with the screw on the top of the HSN and the bottom of the plastic thumb screw should be set to the groove in the HSN body. Sometimes the plastic piece will move up and down around the HSN needle so make sure it is even with the top of the HSN. Those are the factory settings which will run very rich. If it won't start and the motor is broken in you can turn the HSN 1-1.5 turns in (clockwise) which will lean it out and make it easier to start. This should get you close enough to make it run, then follow Robin's instructions on the first page of this thread to the letter. Good luck, I have the k5.9 and it can be a pain but once you get it right it is not as bad as people say. Mine puts a smile on my face every time.
 
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Thanx for the info! The engine is long broken in. It was done before I changed carbs old carb mid needle fell out. runs like it is rich on the top end.The low end is ok. fires up first try. will stall with throttle but goes fine next try. just always seems sluggish
 
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It could be a case where your top end is too rich and your bottom end is out of whack and thats why you are have high idle issues. Try the factory settings and a factory cold plug. Then turn your HSN in 1.5 turns as a start. I run a medium cold plug in mine and it seems fine for my climate. I live on the coast in california. I don't know what plug you are refering to so all I can say is to try the recomended plug for that motor. Here:

http://www.hpiracing.com/products/en/1504/
 
Thanks for the info on " Performance tuning, let the engine tell you " Robin.

It's been very helpful.
 
it all makes too much sense......
 
well I'm no expert but from what i have heard racers tune for performance mostly and don't worry as much about the life of there engine which the average person wouldnt do as they want there engine to last as long as possible
 
i haven't seen this question yet. What happens when it drops below idle and almost dies? And it's spitting quite a bit of fuel through the exhaust?
 
That's the thing I think it's running lean bc the temps get to 230 but I can't find idle. To me it's idleing too high but hpi spec on the .15 is 1.5-2 mm and for some reason I have to set the servo saver back quite a bit to prevent a runaway. And it's running too rich bc wop I'm spewin fuel out. Right now its decently tuned but idle is still higher than my 4.6 savvy.
 
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