Rex2342

Thats what the guy at the hobby shop said too but it only had maybe half a gollon through it but it was changed anyway and it still does the same thing.The truck was bought in december and we broke it on a 50 degree day exacly like the dvd and again after the piston/sleeve was changed but we are still having the same problems.Just so you know he was reinstated to active duty in april and I have his truck and i'm hoping to get it running right before he comes home so we can go out and bash together but since i'm having allot of trouble with this thing it's been sitting for the past couple of weeks.

And just to coment on my tuning skills....I might not be as experienced as allot of people but I just recenly broke in and tuned a hyper 8port and a fantom fr15 and they are both running perfectly fine without any problems(except the broken dogbone on my savage)

JEFFRO503

My Feedback: (9)

You guys seem to be arguing over something , and all seem to be saying just about the same thing , but aren't understanding.


The LOGER FUEL LINE is what i used on my T-maxx , the reason is because , when i would do my high speed pass , then come to a stop or slow down and turn the rig , it would only take about 2 seconds for the motor to stall. the longer fuel line is for additional fuel to be brought to the engine , cause when you make a sharp turn , hit some bumps or whatever , (at least in my truck) , the fuel line sucks air instead of fuel into the line ..........that's all it takes for the motor to stall. I did this to my truck a few weeks ago and the stalling went down about 80% !!!


maybe my explanation doesn't make sence to some of you guys , but for some reason.........IT WORKS!!.....or at least works a little better than before. For some odd reason , it just seems to actually run out of fuel........not sure why? Anywhooo............give it a try , and work with the settings a little , it made a world of difference on my T MAXX.


JEFFRO503

eletrick

My Feedback: (1)

Casey,

Traxxas's said those words "three gallons is way over par for these engines". They also said "if the engine starts easy on the first run and doesn't start for a second, its a good sign the engine is shot".

The fact that you know people with more than 3 gallons is not out of the question, they may run there trucks ricer, than we do, not in a "win the race" type carb setting. (lean)

As for your remark I know nothing, I would say you are incorrect.
I've been in Nitro R/c more than likely, longer than you have been alive. I also worked with traxxas, for many days and hours, trying to figure the start/stall issue. I can safely say, you are sadly mistaken.

btw, I listed my opinion, you are welcome to yours, so chill out!

Richard Newman

eletrick

My Feedback: (1)

No, what I do not understand is, why my trucks ran like a clock
for so long (running on a mx track) and it never needed the extra hose, to keep out vapor locks...............? It along with four others,
now all have the tmax flu.

On this track, there are three foot jumps, and everything else
bad to keep fuel out of the hose, never had an issue till now.

Can you explain that to me?
and this is not an argument, its a general statement/question, some of these guys, need to chill with the name calling before it gets out of control.


Richard Newman






[QUOTE]Originally posted by JEFFRO503

The LOGER FUEL LINE is what i used on my T-maxx , the reason is because , when i would do my high speed pass , then come to a stop or slow down and turn the rig , it would only take about 2 seconds for the motor to stall. the longer fuel line is for additional fuel to be brought to the engine , cause when you make a sharp turn , hit some bumps or whatever , (at least in my truck) , the fuel line sucks air instead of fuel into the line ..........that's all it takes for the motor to stall. I did this to my truck a few weeks ago and the stalling went down about 80% !!!

grampi

I suppose this issue with the 2.5 isn't a big deal for me. I'll run it til it drops, however long that may be, then I'll drop in a Sirio .18. It is frustrating for many people when something like this happens. If Traxxas knows these engines only last 2-3 gallons, then they should offer replacement engines for like $40-$50. I will write to Traxxas and ask if they'd be willing to offer some kind of deal to those having engine problems.

eletrick

My Feedback: (1)

You are correct, its a RIP off. Just the fact that Hobby People is selling new ones for for 110.00 is a slap in every TMax owners face!

Richard Newman

Dlock

I had some stalling problems with my 2.5. I richened up the LSN a bit and they pretty much went away. I still have the standard length of fuel tubing on there. Just throwing out what has been working for me......

grampi

I just sent Traxxas a nice long email addressing all the issues, from their crappy engine, to their lack of kit and parts availbility. I basically told them everyone was looking elsewhere when they were in the market for an MT, and that the T-Maxx is about become history unless they do something immediately to address these issues. I'll let you know what their response was when I get one.

PigMan Buggerus

My Feedback: (6)

I am also having the engine quits after a few high speed passes. Richening (is that a word?) the high end seemed to help quite a bit. I think I am also going to try some longer fuel tubing on the fuel feed line, routed away from the head. The stock location is right up against the head. I could see how this would cause the fuel to vaporize and cause vapor lock. On another note, the sirio .18 that I have seen people taking about, is this a direct replacment engine, just drop it in and go? Will it work with the easy start, or God forbid would i have to use a pull starter?

studysession

How does the longer fuel line make it run cooler? I have not heard that before.

pkuptrk

My Feedback: (2)

I was so frustrated with my rustler with the 2.5 that i ditched it.After about 10 minutes of use it kept overheating. No matter which way i tuned it, this would still happen and traxxas didn't want to know nothing.I have had 4 other guys from my lhs have the same problem.Go with a sirio or can a traxxas all together and get a savage or losi. Or better yet a schumacher.Thats what i got and leaves a smile on my face everytime i have it out.NO PROBLEMS and 70 miles an hour of sick fun.

grampi

Yes, the Sirio is a direct drop-in replacement engine, and the easy start assembly bolts right onto it.

PigMan Buggerus

My Feedback: (6)

Thanks for the info Grampi, did you put the Nova head on your 2.5 yet? And if so, did that help the quiting after the engine is hot problem? Also, if you get the sirio 18, let me know how it compares to the 2.5, and whether it is a little more reliable.

Thanks!

grampi

I do have the Nova head, however, I don't think it did anything for the quitting problem, but the extra length on the pressure line helped quite a bit. Don't ask me how or why this works cause I don't know why. I just know it does.

perculator

I just got a Sirio .18, partially because of the info I have read in this thread and others like it. I find it kind of disturbing to think that the 2.5 is only supposed to run well for 3 gallons or so of fuel.

Is the Sirio like this also? I was hoping to get alot more life out of it that just 3 gallons. After it blows, how much will I have to dish out for a rebuild kit?

Thanks in advance for any advice...

savageforce

The exhaust pulsates and adds air into your tank (sometimes causing foaming). The longer the line, the less "air pockets" you'll get (because it has a chance to balance out). However, if the line is too long you'll lose that pressure you need to force the fuel out of the tank and into the carb. 8-10" is recommended length.

eletrick

My Feedback: (1)

Naaaaaaaah, I'm not buyin it.

Mine ran till it threw the tires off, for three gallons plus, with factory fuel line. Now I need to add fuel line. No WAY!


( I'm a fair person, I tried this mumbo jumbo, on two of my trucks,
when this was put up on Traxxas's board. No effect! And it may somehow help, it from not stalling as much, its by no means a fix!)
I honestly don't think it even helps!

RN

grampi

It may not have done anything for you, but I know for a fact the additional line helped a lot with my Maxx's stalling problem.

eletrick

My Feedback: (1)

In patern planes and in ducted fan jets, we used ArmorAll one spray per gallon to reduce foaming in the fuel tank, but again, I do not think this is the issue.


I really think traxxas has a major issue with these engines. Not with mine, as they were ran for what they call "more than Par" for its engine life. But who knows, maybe they got a bad run of pistons or sleeves.

It will all come out in the wash!

RN
(my little glass ball see's a bunch going on ebay real soon)

eletrick

My Feedback: (1)

Maybe we should start a poll, and ask everyone if its working!!!!

Pink slips say: when the two new engines being replaced by traxxas get here and installed, they run like Richard Prior on fire!
with factory lines?

BET??????

RN

PigMan Buggerus

My Feedback: (6)

ok 1 more question about the Sirio .18, is there 2 versions of this engine? I am seeing 6 port and 8 port. I would guess the 8 port is the one I want?

studysession

My wife and I both have 2.5 TMaxx - I run them a little rich but over all they run great with no problems. She just crashes and floods hers all the time - normal RC stuff.

The big thing I want to know about the Sirio is power. She wants to do wheelies like everytime she pulls the trigger. She loves jumping and wheelies.

grampi

The Sirio is rated at 1.9 hp. I don't think wheelies will be a problem.

eletrick

My Feedback: (1)

what does this engine cost, and who makes it?

grampi

Trinity makes it, and it can be had for $189-$199.