T-Maxx 3.3 bogs down

[srbecker]

I got a question that I am hoping someone can help me out with. I recently tuned my t-maxx for the warmer weather (or so I thought) and it starts pretty easy as well as runs great for a while. Once I come to a stop, it will idle for up to 30 seconds (havent tried longer) and I can punch it right from a stop and it will accelerate no problem, however, after a high speed run, I come to a stop and then punch it again within a few seconds, it seems to bog real bad and the only way to get it to stop is to accelerate slower. Is this simply a result of running too rich still, or could it possibly be overheating? I do have a temp gun but I didnt have it with me today. This is the first time I experienced these issues as well.

Also, just so I know, what are some side effects of an engine running too hot? I appreciate any help that can be given.

---------- Post added at 7:40 PM ---------- Previous post was at 7:27 PM ----------

And just to add, my running temps after a high speed run are around 260-270 however I still have plenty of blue smoke coming out

 

[tmaxxfreek]

i usually run my 3.3 at 250 to 270 to get the best performance, i have seen some run better at 280+ the 3.3's like to run on the warm side, sounds like possibly the LSN too lean, ruchen it about 1/16 at a time and see if it gets better.

 

[srbecker]

i usually run my 3.3 at 250 to 270 to get the best performance, i have seen some run better at 280+ the 3.3's like to run on the warm side, sounds like possibly the LSN too lean, ruchen it about 1/16 at a time and see if it gets better.

Thanks. Just to be on the safe side, I went down and fiddled with it and reset all the settings to factory (4 turns out and LSN flush with inner ring of the throttle arm) and I am going to run it tomorrow night, checking my temps and re-tuning it. Otherwise I would always be fiddling. It doesn't help that I tuned it in the winter lol

 

[srbecker]

Well I went back out today at factory settings and never got to even touch the LSN due to the fact I could not set the HSN. No matter what I did it either bogged out when hitting the gas and then would stall at idle. The only way to start it was to apply throttle while pull starting. I will upload a few videos, but it seems like I might have an air leak? Any other ideas?

 

[srbecker]

I think i found my problem. There is a silver screw ib the right side of the carb. part of the side was chipped, exposing the gasket and more than likely causing an air leak. Sound right? Now on to the more important question, are there any better carbs out there/uprades, or is the stock one the only/best one for the 3.3 engine?

 

[srbecker]

Here is what I believe the culprit was.

 

[SchrodeMode]

I've read about people using the RB Concepts TM523 carb, they say it turns it into a much better engine but the carb goes for well over $100. I've also read about the Ofna Force .26 and .28 carbs as well as the 11K from the OS .21TM, I haven't checked the prices on these though and some say modifications are needed. One guy says the carb from Losi's 3.4 is a direct fit. If you look at the traxxas forums under the Nitro then Slayer you will find a thread with all of these carbs in it.

I HAVE NOT TRIED THESE CARBS so I'm just letting you know what I've read.

 

[srbecker]

I've read about people using the RB Concepts TM523 carb, they say it turns it into a much better engine but the carb goes for well over $100. I've also read about the Ofna Force .26 and .28 carbs as well as the 11K from the OS .21TM, I haven't checked the prices on these though and some say modifications are needed. One guy says the carb from Losi's 3.4 is a direct fit. If you look at the traxxas forums under the Nitro then Slayer you will find a thread with all of these carbs in it.

I HAVE NOT TRIED THESE CARBS so I'm just letting you know what I've read.

Thanks for the insight and efforts. I am not very good with tinkering and custom modifications so I just went with a factory replacement and new exhaust manifold for about 35 bucks combined. I also have a dent in my exhaust manifold, would/could that effect performance or cause bogging, or is it most likely the air leak that was causing that?

 

[tmaxxfreek]

i would say the above picture of the carb is 100% your problem.

 

[srbecker]

i would say the above picture of the carb is 100% your problem.

No poop its my problem haha j/k, but thats good to hear, hopefully Ill be back up and running tonight then. Purchased a new carb body from my LHS, going to swap the needles and plugs over tonight, install it and re tune it. Hopefully that does the trick. Thanks guys

 

[tmaxxfreek]

No poop its my problem haha j/k, but thats good to hear, hopefully Ill be back up and running tonight then. Purchased a new carb body from my LHS, going to swap the needles and plugs over tonight, install it and re tune it. Hopefully that does the trick. Thanks guys

you asked if the dent would cause it, It wont....thats why the carb was 100%

 

[srbecker]

you asked if the dent would cause it, It wont....thats why the carb was 100%

I know, I was just messing with you, sorry if it came off the wrong way haha. Anyways, i replaced the carb body last night, retuned and it seems to be running pretty good now. Maybe a bit too rich, but I will do more fine tuning tonight if the rain holds off. Thanks for all your input!