I'm a noobie and have a ?

[duramax47]

Hi guys I'm kinda new to nitro rc and i have a t-maxx 3.3 4908 and i know a bit about it but after break in and during break in my truck has never had low end; never pops wheelies but great on high end i know how to tune good, so I'm thinking that because i never got it to full running temp when i broke it in last winter that its just not a strong motor. What should i do or is their anything i can do?

 

[bergoff]

What are your temps at? My revo didn't wake up till it hit 265.

 

[Racer 1966]

A proper break-in is crucial to engine performance and life. It's possible that due to a poor break-in you are down on power but the tune could be off. Also how your suspension is setup can affect it's ability to wheelie.

 

[duramax47]

The suspension is stock from traxxas and i range from temps when its cold out i see 160 170 when its warm out i have to shut off early when i see 260 to 285 and i know its tuned as well as it can be so ? what can i do

 

[Racer 1966]

The 160*-170* temps are too low for proper performance and can actually shorten engine life. The 260*-285* isn't excessive.
The 3.3 should be able to wheelie but if you KNOW the tune is right on my only suggestion is to stiffen the rear suspension. Thicker shock oil,heavier springs and or add spring spacers.

 

[duramax47]

ya i know its tuned right but it has no low end and when i give it gas it lags tell it gets some speed up so I'm pretty sure its the motor i think because of poor break in it could use a rebuild with proper break in and a diff fuel cause i think traxxas 20% is way to oily what do you think about that idea?

 

[Metalhead Matt]

I'd try to richen the hsn a tad and lean the lsn. If you can't tune the bog out and are certain the engine is sealed, you may just want to grab a piston and sleeve. Some better bearings are a good idea on a 3.3 as well.

 

[duramax47]

how do i know if its sealed good? and if i do rebuild what parts do you recomend i get to rebuild with metalhead matt?


Thanks to all of you this is a great help!

 

[Racer 1966]

Traxxas fuel is oily but I never noticed a big loss of performance with it. I haven't used it for a few years no though.
Sounds like you could be a little rich on the low side. Try leaning it a little,you may need to compensate some by richening the HSN. Have you checked the slipper clutch?

 

[2revo1maxx]

It sounds like it's not tuned right, but good luck, I had one hell of a time with my 4908. Once I got it tuned it still wouldn't hold.

 

[Metalhead Matt]

There's ways to test it. Brush soapy water on leak-prone areas while blowing through the pressure line and plugging the fuel line. It's best to seal an engine before even running it. Even new. The hsn housing on traxxas carbs is prone to leaks in my experience as well.

 

[duramax47]

ya the slipper is tight but not over tight i will try again with tuning tomorrow I'm pretty sure i got it as good as it can be i mean I'm on the 4 gallon and never have seen low end no wheelies

 

[Metalhead Matt]

It could probably use a rebuild. Running it at low temps put excessive wear on it and that's a decent amount of fuel. I'm not exactly sure what parts you'll need. I think piston/sleeve, bearings, conrod and bushing. I haven't had to rebuild one yet. Just read about it on here. I'd probably just trade mine in anyways.

 

[duramax47]

just send it back to traxxas and get a new one for like 80bucks or something then and start over and do it right this time


Hey i wanna thank all of you guys your a great help can't thank you enough!

 

[Racer 1966]

4th gallon? Oh, your engine is more used than I was thinking but the low end lag still isn't right. If it won't tune out you may need to rebuild or if it starts good and runs good otherwise,just suffer without wheelies.

 

[Metalhead Matt]

It's great to help out.

 

[duramax47]

true but i think I'm ganna get a new one so i have a power house like i should of had you know I'm just dumb and broke it in in the wrong weather

 

[Predat0r]

Sounds like a tuning issue to me, you keep saying its tuned "perfectly"

How exactly do you know this?

Have you tried leaning the lsn and richening the hsn?

How long have you been tuning these engines to know its tuned "perfectly"?

 

[duramax47]

well its my second truck i live at high altutude and i travel to cali alot and i take my trucks with me and i have to retune every time for diff temps altitude air density and stuff like that and they perform great just have never has low end for wheelies and stuff so i would say I'm pretty good just not an expert

 

[2revo1maxx]

I would get it warmed up, then adjust the idle and lsn til the lsn is flush with the barrel and it will idle for 15 seconds without quitting or loading up. I recently learned that the 3.3 will seem like it's tuned ok even with the lsn 1.5 turns out from flush. I was relying on a lean hsn for throttle response and it wouldn't idle very good because the lsn was so rich, plus it had very little low end punch.