Hi, I'm running a traxxas 3.3 engine. I've read the "tuning bible" and a couple of others also and they talk about needle balance. I can't help but believe that I'm close to a good tune but it still gets hot...takes about 3 or 4 minutes or quicker if ya don't give it a rest.
I've sealed the motor using the copper coat sealer and that made all the difference in the world as far as a consistant idle. The little truck seems to run and idle good. I have plenty of smoke at wot and when at idle, the engine will begin to cool down.
Does anyone have any more ideas? There is no binding anywhere that I can see.
Thanks

Define "still gets hot". The TRX 3.3 is somewhat known to like running at the upper end of what would be considered normal. If its running consistant, producing smoke, and idles well I would not worry about it temping 250-260 after several WOT runs.

R u temping with temp gun if so what r the temps like

the temp is upward of 290 and 300 degrees. I have a Spektrum telemetry temp sensor. I can monitor the temp very well using that. If anything, the temps may be 5 to 8 degrees hotter when using a temp gun.
When it gets around 290 or 300, I let it cool down

Try setting your high speed screw richer (note where it's set before you do).
If it still runs well, you might have had it set a little too lean.

If it blubbers at large throttle settings after doing this, go back to the previous setting. Mixture isn't what's causing the heat.

My HPI Savage always ran at 290-310*F when tuned properly. Monster trucks don't always do a good job of ventilating the engine well. Do you have a hole cut in your windshield?

I ran a tank through it last nite. I also richened it up to the point of "blubbering" and it didn't help. I was running without the body at the time of tuning. I do not have a hole in the windsheild but the body wasn't on either.
Thanks for the reply

Getting a little better ventilation to the engine will help. 3.3's always seem to run a little on the hot side. Lots of smoke at WOT doesn't mean it is plenty rich. tune for performance, keep richening the top til there is a drop in performance.

What fuel and plug are you running?

when you say it always ran between 290 and 310....did it settle out at those temps or would it continue to get hotter?

fuel is Traxxas 20% and the plug is a standard traxxas revo plug. I don't have the number in front of me at the moment.

What type of fuel are you running ?

Also do not trust the Spektrum temp meter...they are insanely inaccurate....I wouldn't trust what it says even if my temp gun agrees with it, as I do not trust temp guns either.....use the spit test instead !

always tune an engine to run nice..leave the temp guns at home..if in doubt use the spit test on the cooling head...if it sizzles off instantly then it is too hot.....if it boils off in a couple of seconds your perfectly fine..... I know it sounds primitive, but it is more consistent then those silly Spektrum temp probes...

A properly tuned engine should not continue to get hotter the longer you run it. If tuned properly, the temp will stay consistant once it reaches operating temp and the chassis becomes heat saturated. In most cases, when engines continue to get hotter the longer you run them, the needles are not "balanced". Generally you end up with a too fat low needle and too lean top needle. Try richening the top 2 hours and leaning the bottom 2-3 hours.

Yeah, I realize there is room for error but it works good to see if the temp is settling or climbing. it seems like it only climbs. The engine has some wear but I'm going to run it till it runs no more...lol.
I'd just kinda like to figure out this tuning thing before I replace with a new engine someday.
Thanks

Yes, I read that in the "tuning bible" article...I leaned the lsn till it became hard to start and richened to hsn till it was too rich. That didnt help so I returned to the original settings.

Check your Idle gap. It needs to be .5 to .7 MM, then tune around that. Use the low speed needle to set the idle speed. See ( new werks B5) on RC tech, page 1. This way of tuning is new to me, but it works great.